Vacuum purge valve? Will unplugging electric connection have any negative effect?

January 13

Just got around to removing the charcoal can off my R1150R.

So I was going to completely remove this vent line that came off of the charcoal can when I saw the electrical connection to the purge valve. I rewatched the C Harris video and he just unplugs the connection without really explaining it and trashes the purge valve. I just want to make sure it won't have any negative effects. I plugged the line with one of the bolts for now. Sorry about the poor pic, looking from above as I didn't take the side panel off.

Is it my imagination or does the bike run better without the can? It seems the twitchy rpms @3000 went away.

January 13

i pulled my lines all the way to throttle bodies and capped. I was told unplugging wont effect anything. Only issue I had was figuring out how to tuck plug inside frame pointing down so it didnt fill full of water and cause a issue. I had charcoal in plugging other hoses from canister and had charcoal in fuel tank. Needless to day screen and fuel filter where also black with charcoal.

January 13

1 hour ago, Redfoxx said:

i pulled my lines all the way to throttle bodies and capped. I was told unplugging wont effect anything. Only issue I had was figuring out how to tuck plug inside frame pointing down so it didnt fill full of water and cause a issue. I had charcoal in plugging other hoses from canister and had charcoal in fuel tank. Needless to day screen and fuel filter where also black with charcoal.

Afternoon Redfoxx

Did you remove the very fine filter screens from you fuel injector inlets & check those for carbon particles (those fine mesh injector screens can plug up fairly easily), or at least partially plug up then restrict full engine power?

January 13

4 hours ago, johnnyseko said:

Just got around to removing the charcoal can off my R1150R.

So I was going to completely remove this vent line that came off of the charcoal can when I saw the electrical connection to the purge valve. I rewatched the C Harris video and he just unplugs the connection without really explaining it and trashes the purge valve. I just want to make sure it won't have any negative effects. I plugged the line with one of the bolts for now. Sorry about the poor pic, looking from above as I didn't take the side panel off.

Is it my imagination or does the bike run better without the can? It seems the twitchy rpms @3000 went away.

Afternoon johnnyseko

Just unplug the evap canister purge solenoid then zip tie it to the frame out of the way under a panel. Nothing will happen as that circuit isn't monitored for faults. In fact that connector isn't even used in countries that don't have evaporation emission laws (ie no black canister)

January 13

1 hour ago, dirtrider said:

Afternoon Redfoxx

Did you remove the very fine filter screens from you fuel injector inlets & check those for carbon particles (those fine mesh injector screens can plug up fairly easily), or at least partially plug up then restrict full engine power?

DR I will gladly do if I can get some specifics where they are at and how to get to? I got new strainer for fuel pump since current one is black too. I researched and found location. do you pull them with metal hook or is there a better way.

I wont be so BMW Newbie by spring as my list of things wrenched is getting longer than unwrenched.

Good news is I just got my Wisconsin Collectors License plate for RT. No more registration fees.

January 13

Thanks guys! Next on the list will be the fuel filter. Will be interesting to see if there's any black sludge.

January 13

16 minutes ago, johnnyseko said:

Thanks guys! Next on the list will be the fuel filter. Will be interesting to see if there's any black sludge.

While your in there you may want to do fuel hoses and strainer too. I did everything but one section of fuel hose and strainer. I regret now not doing all at once since I will have to go back in some time. I did not replace the 2 vent hoses, since they looked good and have not pressure. I should have took photo of charcoal in fuel tank, looked like mouse poop.

January 13

1 hour ago, Redfoxx said:

DR I will gladly do if I can get some specifics where they are at and how to get to? I got new strainer for fuel pump since current one is black too. I researched and found location. do you pull them with metal hook or is there a better way.

I wont be so BMW Newbie by spring as my list of things wrenched is getting longer than unwrenched.

Good news is I just got my Wisconsin Collectors License plate for RT. No more registration fees.

DR

Do you know if that micro filter screen size is 6mm x 3mm x 12mm, I see that size readily available lots of different injectors and now seen several tools to remove. Also looks like I could use a screw and fuel line pliers to remove.

RF

January 13

1 hour ago, Redfoxx said:

DR I will gladly do if I can get some specifics where they are at and how to get to? I got new strainer for fuel pump since current one is black too. I researched and found location. do you pull them with metal hook or is there a better way.

I wont be so BMW Newbie by spring as my list of things wrenched is getting longer than unwrenched.

Good news is I just got my Wisconsin Collectors License plate for RT. No more registration fees.

Evening Redfoxx

I usually just turn a screw into then then remove with pilers or side cutters on the screw. But I always have some new ones to pop in so I don't care if I ruin them getting it out.

To not ruin one you can try a dental pick or small hooked wire or even a crochet hook.

If I was trying to save the strainer I would remove the injector, then put a 9 volt battery on the + & - injector terminals, then spray carb cleaner into the injector, then try blowing compressed air back through it.

If the strainer is plugged that will probably blow the strainer out. If it isn't plugged up to bad with hardened on carbon then the carb cleaner will probably flush & clean it.

January 13

31 minutes ago, Redfoxx said:

While your in there you may want to do fuel hoses and strainer too.

Good call! Thanks. I didn’t even know you could get the strainer only, separate from the pump.
I’ve got a long and growing list. Got the filter with the tune up kit but when I realized the fuel tank had to come off the parts list to order grew. Also the researching because I figure I’ve gotta bleed the dreaded ABS module while I’m in there.

January 13

6 minutes ago, johnnyseko said:

Good call! Thanks. I didn’t even know you could get the strainer only, separate from the pump.
I’ve got a long and growing list. Got the filter with the tune up kit but when I realized the fuel tank had to come off the parts list to order grew. Also the researching because I figure I’ve gotta bleed the dreaded ABS module while I’m in there.

I bought my 04 RT in August, I would put my done list in here but it might depress you. I look at my to do seem pretty short now.

I did replace my rubber lines to braided, replaced all the brakes pads and bleed the entire system. Buy at least 1 quart bottle of dot 4. I had nasty fluid come out of ABS.

I am trying to decide if I should drain fuel again from tank and finish strainer and fuel line that comes off of pump only piece I didnt do because I didnt have strainer at the time and was kind of staying away from that 21 year old pump since the hose goes onto a plastic fitting on pump. I replaced plastic fuel line quick disconnects with metal, and new hose and used one of old plastic connector with about 18 inches of hose to make a fuel tank drain hose works slick. just remember that tank can hold more than 5 gallons, so 2 gas cans. Now might be the time since its winter, and if I have to order more parts not as big a deal since it supposed to be below zero out all week.

January 13

31 minutes ago, Redfoxx said:

I am trying to decide if I should drain fuel again from tank and finish strainer and fuel line that comes off of pump only piece I didnt do because I didnt have strainer at the time and was kind of staying away from that 21 year old pump since the hose goes onto a plastic fitting on pump. I replaced plastic fuel line quick disconnects with metal, and new hose and used one of old plastic connector with about 18 inches of hose to make a fuel tank drain hose works slick. just remember that tank can hold more than 5 gallons, so 2 gas cans. Now might be the time since its winter, and if I have to order more parts not as big a deal since it supposed to be below zero out all week.

Evening Redfoxx

Of all the fuel lines & parts in your BMW motorcycle that submersible high pressure "U" shaped hose out of the fuel pump is the most likely thing to cause you an engine quit & walk-home. If that U hose blows a split or pin hole on the road then it is a real nightmare as it won't be ridable.

And a fair number of those U hoses have split, or popped a pin hole, when the fuel gets hot while on the road far from home.

January 13

2 minutes ago, dirtrider said:

Evening Redfoxx

Of all the fuel lines & parts in your BMW motorcycle that submersible high pressure "U" shaped hose out of the fuel pump is the most likely thing to cause you an engine quit & walk-home. If that U hose blows a split or pin hole on the road then it is a real nightmare as it won't be ridable.

And a fair number of those U hoses have split, or popped a pin hole, when the fuel gets hot while on the road far from home.

DR

That section I replaced, I didnt get the short piece off the top of the fuel pump replaced. Since pump top was plastic I stayed away, and I didnt have a strainer at the time I was in there either.

RF

January 13

5 minutes ago, dirtrider said:

And a fair number of those U hoses have split, or popped a pin hole

not if, but when.

January 14

I have seen the Harris videos where he contends black sludge in the fuel filter is charcoal dust.

I have a non-stock fuel pump with out a cannister filter. It has a 'sock' filter. I have the cannister and vacuum control valve. 50k miles

What I have noticed on my 2000 oil head, is that the fuel resistant hoses to the filler cap are shedding rubber. The evidence is black soot on my hands from handling the hoses.

I think this is a source of the soot/sludge/black deposits in the fuel filter.

Thinking about the possibility of charcoal being sucked into the fuel tank, I am not understanding how charcoal particles would travel from the cannister to the fuel tank.

As I understand it, the fumes from the fuel tank are vented to the cannister, absorbed by the charcoal medium.

When the engine warms [or time elapses] the computer activates the vacuum control valve allowing manifold vacuum into the cannister, to purge the cannister of fumes AND allows atmospheric pressure air to enter the fuel tank to release pressure [due to temperature increase. Think bike parked in the hot sun.] and vacuum relief due to fuel consumption.

The only vacuum FROM the fuel tank that COULD suck charcoal dust into the fuel tank would result from fuel consumption when the vacuum control valve opens, BRIEFLY.

In conclusion, I can not think of a force to cause cannister charcoal dust to travel into the fuel tank, and, that the black deposits are due to fuel hose deterioration.

January 14

3 hours ago, The Fabricator said:

I have seen the Harris videos where he contends black sludge in the fuel filter is charcoal dust.

I have a non-stock fuel pump with out a cannister filter. It has a 'sock' filter. I have the cannister and vacuum control valve. 50k miles

What I have noticed on my 2000 oil head, is that the fuel resistant hoses to the filler cap are shedding rubber. The evidence is black soot on my hands from handling the hoses.

I think this is a source of the soot/sludge/black deposits in the fuel filter.

Thinking about the possibility of charcoal being sucked into the fuel tank, I am not understanding how charcoal particles would travel from the cannister to the fuel tank.

As I understand it, the fumes from the fuel tank are vented to the cannister, absorbed by the charcoal medium.

When the engine warms [or time elapses] the computer activates the vacuum control valve allowing manifold vacuum into the cannister, to purge the cannister of fumes AND allows atmospheric pressure air to enter the fuel tank to release pressure [due to temperature increase. Think bike parked in the hot sun.] and vacuum relief due to fuel consumption.

The only vacuum FROM the fuel tank that COULD suck charcoal dust into the fuel tank would result from fuel consumption when the vacuum control valve opens, BRIEFLY.

In conclusion, I can not think of a force to cause cannister charcoal dust to travel into the fuel tank, and, that the black deposits are due to fuel hose deterioration.

How it does it is for an engineer, all I can tell you the vent line back to the tank was full of charcoal and the the line to the vacuum control valve was full of charcoal. I removed all lines and tapping them charcoal would fall out. I had at least 50 pieces of charcoal in my fuel tank looked like mouse poop. When I re-open my tank to change my strainer, I will photo it. it is black, guessing it should be white or maybe green. I cut open my fuel filter and one side of the filter paper was black and the other was tan. my charcoal canister was full of fluid. The bike had 60,000 miles, I had just bought it and at that time I had less than 1000 miles on it. All my hoses inside the tank looked good and not showing any caulking, cracking or brittle. Replaced most anyhow. My tank was vent was not venting and the tank would build. vacuum.

January 14

On 1/13/2024 at 7:51 PM, The Fabricator said:

I have seen the Harris videos where he contends black sludge in the fuel filter is charcoal dust.

I have a non-stock fuel pump with out a cannister filter. It has a 'sock' filter. I have the cannister and vacuum control valve. 50k miles

What I have noticed on my 2000 oil head, is that the fuel resistant hoses to the filler cap are shedding rubber. The evidence is black soot on my hands from handling the hoses.

I think this is a source of the soot/sludge/black deposits in the fuel filter.

Thinking about the possibility of charcoal being sucked into the fuel tank, I am not understanding how charcoal particles would travel from the cannister to the fuel tank.

As I understand it, the fumes from the fuel tank are vented to the cannister, absorbed by the charcoal medium.

When the engine warms [or time elapses] the computer activates the vacuum control valve allowing manifold vacuum into the cannister, to purge the cannister of fumes AND allows atmospheric pressure air to enter the fuel tank to release pressure [due to temperature increase. Think bike parked in the hot sun.] and vacuum relief due to fuel consumption.

The only vacuum FROM the fuel tank that COULD suck charcoal dust into the fuel tank would result from fuel consumption when the vacuum control valve opens, BRIEFLY.

In conclusion, I can not think of a force to cause cannister charcoal dust to travel into the fuel tank, and, that the black deposits are due to fuel hose deterioration.

Thinking about the possibility of charcoal being sucked into the fuel tank, I am not understanding how charcoal particles would travel from the cannister to the fuel tank.

___________________________________________________________________________________

Morning Fabricator

You need to fully understand how the evaporation system works?

The black evap canister not only TRAPS & HOLDS vented hydrocarbons but it is also the VENT path for the fuel tank to atmosphere.

When just sitting (not ridden) the fuel tank heat & cools, and/or as the atmospheric pressure changes with weather changes, so the fuel tank needs to both breathe OUT as the internal pressure exceeds external pressure or breathe IN if the external pressure exceeds the internal pressure (this is pretty well a continuous thing as there is a little venting out-of or in-to the tank during each day. Not a lot but some two way venting is going on even on a parked motorcycle.

On the out-venting, the charcoal catches & holds the vented hydrocarbons. Then when the engine is warm & running at a decent RPM AND (*all conditions are met to accept the stored hydrocarbons), the Motronic opens the tank vent valve then engine vacuum sucks those stored hydrocarbons into the engine & the engine burns them then runs them through the cat converter.

This is pretty straight forward & you seem to have a handle on this part.

Now on how the carbon actually gets into the fuel tank____

It usually doesn't come in as a dust but more of as a goo, or damp carbon particles, this ends up in the fuel tank or dries to a dust type deposit in the vent system hoses & vent valve.

A little of the carbon can get in during the continuous breathing of the fuel tank out & in, not a lot this way but over time some can come in this way.

The majority of the Evap canister carbon comes into the fuel tank during riding the motorcycle. As was mentioned above the fuel tank also VENTS IN through the carbon in the Evap canister. THIS is where most of the carbon finds it's path into the fuel tank.

When fuel is used out of the fuel tank while riding that fuel volume needs to be replaced with the same volume of atmospheric air. If it couldn't get that atmospheric air IN to replace the amount of fuel used then it would suck the sides of the plastic fuel tank in & crush the fuel sender tube (this happens with the plastic tank BMW's). On metal tank BMW's the lack of tank venting would eventually prevent the fuel from flowing out of the fuel tank.

In any case, the fuel tank MUST vent outside air IN as the fuel is pumped OUT. If you use 5 gallons of fuel out of the fuel tank while riding then it takes in 5 gallons of air IN (by volume) to replace that used fuel. Multiply this by the number of gallons that you have used in the last month, or year, or years & THAT is a LOT of air vented INTO the fuel tank through the Evap canister.

As mentioned above the fuel tank gets that outside air IN through the Evap canister, so once the Evap canister carbon becomes goo or degrades then some of that carbon gets sucked in with the make-up air.

Now how does the carbon in the Evap canister turn to goo or degrade? Basically two ways___

One way is overfilling the fuel tank with cold or cool fuel then parking in a hot area or in the sun. The fuel then expands forcing raw liquid fuel into the Evap canister (that raw fuel can eventually degrade & break the carbon down).

The second way, & it might be worse than the above overfilling, is road water coming in through the Evap canister external vent hose (the one that terminates behind the riders R/H foot peg). That vent hose hangs down where road spray from the front tire & road splash can get to it (this is continuous when riding in the rain).

The problem here is, not only is the end of that hose open to water spray but from the factory it is cut straight & square. THIS is the main way water enters the Evap canister & turns the carbon to a black goo that gets sucked into the fuel tank.

That straight cut exit of the vent hose probably doesn't allow a lot of water spray directly into the hose BUT it does set up another very big problem. That is, any water contacting the hose farther up then running down the hose can form large droplets of water on the very bottom of the hose, & those large droplets can & will get sucked up into the hose then into the carbon in the Evap can, then into the fuel tank as a wet carbon goo.

Most dealers didn't know this, or at least didn't pay attention to it, or didn't care, but BMW published an important service bulletin to cut the bottom of the vent hose (the one terminating behind the riders R/H foot peg) to a 45° angle. This allows road water to drip off the very bottom without getting sucked into the Evap canister (or sucked directly into the fuel tank if no Evap canister present).

January 14

16 hours ago, Redfoxx said:

I bought my 04 RT in August, I would put my done list in here but it might depress you. I look at my to do seem pretty short now.

I did replace my rubber lines to braided, replaced all the brakes pads and bleed the entire system. Buy at least 1 quart bottle of dot 4. I had nasty fluid come out of ABS.

I'm sure we have similar lists! I'm enjoying working on the bike so far. Thankfully not too many miles on it. Trying to get as much done now before the weather warms up. Looking at a really cold week ahead here.

January 14

15 minutes ago, johnnyseko said:

I'm sure we have similar lists! I'm enjoying working on the bike so far. Thankfully not too many miles on it. Trying to get as much done now before the weather warms up. Looking at a really cold week ahead here.

What is really cold, I have -4 outside right now. :-)

January 15

That's interesting about the injector filter screens I never thought about cleaning them. I sent both injectors out for testing and cleaning when I found my R1100RSL about 12 years ago but have never given a thought to cleaning the screens. Also, I've never heard of anyone doing it. Makes me wonder how common a problem dirty filter screens actually are. I assume all injectors have these filter screens? Always just assumed the in tank fuel filter would do the job. Should this be part of regular preventive maintenance? Would be easy on the BMW but not so much fun on a certain 4 cylinder beast I'm familiar with.

January 15

8 hours ago, JamesW said:

That's interesting about the injector filter screens I never thought about cleaning them. I sent both injectors out for testing and cleaning when I found my R1100RSL about 12 years ago but have never given a thought to cleaning the screens. Also, I've never heard of anyone doing it. Makes me wonder how common a problem dirty filter screens actually are. I assume all injectors have these filter screens? Always just assumed the in tank fuel filter would do the job. Should this be part of regular preventive maintenance? Would be easy on the BMW but not so much fun on a certain 4 cylinder beast I'm familiar with.

Morning James

The injector filters are basically "micro filters". In most cases the pump sock (inlet screen) catches the larger things, the actual fuel filter catches most of the remainder of junk, with the injector micro filters catching very fine particles that slip through, or things that recombine in the fuel flow after getting through the main fuel filter.

Those micro filters seldom get plugged if the fuel filter is working. But when it comes to the Evap canister carbon, some of that stuff seems to get through to the injector micro screens.

If you use good quality fuel & don't have an Evaporation canister then most likely your injector screens are just fine.

On older motorcycles (with fuel problems, past fuel contamination problems, or possibly degraded Evap canisters) I will sometimes cut the fuel filter apart then spread the filter element out looking for what it caught. If I see black carbon or extremely fine residue I will usually replace the injector screens (micro filters). They are cheap & not that difficult to replace.

The time you really need to look at those micro filters is on a motorcycle that has been sitting (or stored) with old skunky fuel in it, especially if some type of strong fuel system cleaner is used in the fuel tank to try to break up the varnish.

And obviously check the micro filters after Evap canister carbon is found in the fuel system.

January 15

Yeah, when I bought my zero miles BMW the fuel pump was frozen and you could hardly blow through the fuel filter so new filter and filter sock then sent the injectors out for cleaning and balance testing. The motorcycle had the original fuel in the tank (small quantity) that was used at the factory when it was dyno tested before shipment to the original owner and he never ever even started the bike. The fuel was nothing but varnish....nasty stuff. Did all this before ever starting the bike also removed the carbon canister as well then fired her up . This was all in 2012 so 19 years after production in '93. The original sock was not in good shape so new sock, fuel lines, filter. Today she's the best BMW I ever owned and I wouldn't trade it for a new one not ever!

January 15

I just had my tank apart, 2004 RT with 52K miles. The vent going through the metal plate that attaches and holds the fuel pump was rusted solid, no venting. Also the water hole under the fuel cap was rusted solid, could not blow through either. I cleaned both with a small steel galvanized wire, electric fence wire. Moral of the story blow through all your hosed to make sure they are not plugged.

I also just removed the charcoal canister, electric valve, and all vacuum lines. Full of charcoal !!

Thanks for letting us know about the fine screens in the injectors, I didn't know about those..

January 15

1 hour ago, TowerMonkey said:

I just had my tank apart, 2004 RT with 52K miles. The vent going through the metal plate that attaches and holds the fuel pump was rusted solid, no venting. Also the water hole under the fuel cap was rusted solid, could not blow through either. I cleaned both with a small steel galvanized wire, electric fence wire. Moral of the story blow through all your hosed to make sure they are not plugged.

I also just removed the charcoal canister, electric valve, and all vacuum lines. Full of charcoal !!

Thanks for letting us know about the fine screens in the injectors, I didn't know about those..

Afternoon Jerry

The actual vent metal tube passing through the fuel pump pass-through plate seldom if ever rusts solid. But the other metal tube for the fuel cap ring drain is noted for rusting shut.

If your actual tank vent metal tube was rusted shut then someone in the motorcycle's past history probably put the tank vent hose on the incorrect pass-through metal fitting.

January 15

On 1/14/2024 at 4:41 AM, dirtrider said:

Thinking about the possibility of charcoal being sucked into the fuel tank, I am not understanding how charcoal particles would travel from the cannister to the fuel tank.

___________________________________________________________________________________

Morning Fabricator

You need to fully understand how the evaporation system works?

The black evap canister not only TRAPS & HOLDS vented hydrocarbons but it is also the VENT path for the fuel tank to atmosphere.

When just sitting (not ridden) the fuel tank heat & cools, and/or as the atmospheric pressure changes with weather changes, so the fuel tank needs to both breathe OUT as the internal pressure exceeds external pressure or breathe IN if the external pressure exceeds the internal pressure (this is pretty well a continuous thing as there is a little venting out-of or in-to the tank during each day. Not a lot but some two way venting is going on even on a parked motorcycle.

On the out-venting, the charcoal catches & holds the vented hydrocarbons. Then when the engine is warm & running at a decent RPM AND (*all conditions are met to accept the stored hydrocarbons), the Motronic opens the tank vent valve then engine vacuum sucks those stored hydrocarbons into the engine & the engine burns them then runs them through the cat converter.

This is pretty straight forward & you seem to have a handle on this part.

Now on how the carbon actually gets into the fuel tank____

It usually doesn't come in as a dust but more of as a goo, or damp carbon particles, this ends up in the fuel tank or dries to a dust type deposit in the vent system hoses & vent valve.

A little of the carbon can get in during the continuous breathing of the fuel tank out & in, not a lot this way but over time some can come in this way.

The majority of the Evap canister carbon comes into the fuel tank during riding the motorcycle. As was mentioned above the fuel tank also VENTS IN through the carbon in the Evap canister. THIS is where most of the carbon finds it's path into the fuel tank.

When fuel is used out of the fuel tank while riding that fuel volume needs to be replaced with the same volume of atmospheric air. If it couldn't get that atmospheric air IN to replace the amount of fuel used then it would suck the sides of the plastic fuel tank in & crush the fuel sender tube (this happens with the plastic tank BMW's). On metal tank BMW's the lack of tank venting would eventually prevent the fuel from flowing out of the fuel tank.

In any case, the fuel tank MUST vent outside air IN as the fuel is pumped OUT. If you use 5 gallons of fuel out of the fuel tank while riding then it takes in 5 gallons of air IN (by volume) to replace that used fuel. Multiply this by the number of gallons that you have used in the last month, or year, or years & THAT is a LOT of air vented INTO the fuel tank through the Evap canister.

As mentioned above the fuel tank gets that outside air IN through the Evap canister, so once the Evap canister carbon becomes goo or degrades then some of that carbon gets sucked in with the make-up air.

Now how does the carbon in the Evap canister turn to goo or degrade? Basically two ways___

One way is overfilling the fuel tank with cold or cool fuel then parking in a hot area or in the sun. The fuel then expands forcing raw liquid fuel into the Evap canister (that raw fuel can eventually degrade & break the carbon down).

The second way, & it might be worse than the above overfilling, is road water coming in through the Evap canister external vent hose (the one that terminates behind the riders R/H foot peg). That vent hose hangs down where road spray from the front tire & road splash can get to it (this is continuous when riding in the rain).

The problem here is, not only is the end of that hose open to water spray but from the factory it is cut straight & square. THIS is the main way water enters the Evap canister & turns the carbon to a black goo that gets sucked into the fuel tank.

That straight cut exit of the vent hose probably doesn't allow a lot of water spray directly into the hose BUT it does set up another very big problem. That is, any water contacting the hose farther up then running down the hose can form large droplets of water on the very bottom of the hose, & those large droplets can & will get sucked up into the hose then into the carbon in the Evap can, then into the fuel tank as a wet carbon goo.

Most dealers didn't know this, or at least didn't pay attention to it, or didn't care, but BMW published an important service bulletin to cut the bottom of the vent hose (the one terminating behind the riders R/H foot peg) to a 45° angle. This allows road water to drip off the very bottom without getting sucked into the Evap canister (or sucked directly into the fuel tank if no Evap canister present).

I am aware of continual air flow in and out of the fuel tank via the cannister.

That makes sense to me about how the charcoal becomes 'goop' and how it is sucked into the fuel tank.

What are *all conditions are met to accept the stored hydrocarbons ?

January 15

15 hours ago, The Fabricator said:

I am aware of continual air flow in and out of the fuel tank via the cannister.

That makes sense to me about how the charcoal becomes 'goop' and how it is sucked into the fuel tank.

What are *all conditions are met to accept the stored hydrocarbons ?

Afternoon Fabricator

I don't know all that are required but the biggies are -- engine temperature, throttle opening position, engine RPM, closed loop operation, CCP selection, (possibly intake air temperature but I don't know this for sure).

January 25

On 1/15/2024 at 11:57 AM, dirtrider said:

Afternoon Jerry

The actual vent metal tube passing through the fuel pump pass-through plate seldom if ever rusts solid. But the other metal tube for the fuel cap ring drain is noted for rusting shut.

If your actual tank vent metal tube was rusted shut then someone in the motorcycle's past history probably put the tank vent hose on the incorrect pass-through metal fitting.

DR,

My cap vent rusted solid going through the fuel pump plate. Had to use a drill bit from both directions and then a wire and air line.

RF

January 25

11 hours ago, Redfoxx said:

DR,

My cap vent rusted solid going through the fuel pump plate. Had to use a drill bit from both directions and then a wire and air line.

RF

Morning RF

That is pretty common on the old BMW 1100/1150RT's.

It will rust shut again if you don't keep it open, as once the rusting starts, it will re-rust due to the fitting metal coating being compromised.

On my old 1100/1150 bikes I would squirt a shot of WD-40 into the drain hole in the tank fill cap ring about once a month & give it a few WD-40 treatments spaced a couple of days apart just before winter storage.

Never wash your motorcycle then park it for a while (especially if your water is on a water softener system) as that water will sit in that pass-through fitting & quickly re-rust it shut.

WD-40 seems to be the safest as it is very low pressure & leaves a little (W)ater (D)isplacement fluid inside the drain hose & pass-through fitting.

Do not use (un-regulated) compressed shop air as that can blow (or partially blow) the hose off the fitting inside the fuel tank. If that hose comes off (or comes loose enough to leak) it can drain a half a tank of gasoline into you garage or storage area overnight. (not a good situation)

January 25

2 hours ago, dirtrider said:

Morning RF

That is pretty common on the old BMW 1100/1150RT's.

It will rust shut again if you don't keep it open, as once the rusting starts, it will re-rust due to the fitting metal coating being compromised.

On my old 1100/1150 bikes I would squirt a shot of WD-40 into the drain hole in the tank fill cap ring about once a month & give it a few WD-40 treatments spaced a couple of days apart just before winter storage.

Never wash your motorcycle then park it for a while (especially if your water is on a water softener system) as that water will sit in that pass-through fitting & quickly re-rust it shut.

WD-40 seems to be the safest as it is very low pressure & leaves a little (W)ater (D)isplacement fluid inside the drain hose & pass-through fitting.

Do not use (un-regulated) compressed shop air as that can blow (or partially blow) the hose off the fitting inside the fuel tank. If that hose comes off (or comes loose enough to leak) it can drain a half a tank of gasoline into you garage or storage area overnight. (not a good situation)

DR

was trying to come up with way to seal better metal, I thought about glass bead blasting elbow to remove as much rust as I could, than coating with a thin layer 2 part epoxy, So far I am up to spray metal protector down vent. I did order new exterior hose since its very stiff. Interior hose has a some small cracks in exterior layer. I think that is going to be wait until i do fuel filter next time to replace, guessing it would be this fall. Looked like Motorworks UK had the lowest price lines, but I don't have anything but hose to order right now.

I would guess by fall I will have a parts order. It is a 21 year old bike. :-)

Don't think its warm enough to mess with injector filter baskets yet.

RF

January 25

9 minutes ago, Redfoxx said:

DR

was trying to come up with way to seal better metal, I thought about glass bead blasting elbow to remove as much rust as I could, than coating with a thin layer 2 part epoxy, So far I am up to spray metal protector down vent. I did order new exterior hose since its very stiff. Interior hose has a some small cracks in exterior layer. I think that is going to be wait until i do fuel filter next time to replace, guessing it would be this fall. Looked like Motorworks UK had the lowest price lines, but I don't have anything but hose to order right now.

I would guess by fall I will have a parts order. It is a 21 year old bike. :-)

Don't think its warm enough to mess with injector filter baskets yet.

RF

Morning RF

With the (Interior hose has a some small cracks in exterior layer) just keep in mind that if EITHER the vent or the drain hose, splits, degrades, or has ply separation then it can dump any fuel that is pump-pass-through or higher into your storage area (actually any fuel above the hose rupture point)

January 25

2 hours ago, dirtrider said:

Morning RF

With the (Interior hose has a some small cracks in exterior layer) just keep in mind that if EITHER the vent or the drain hose, splits, degrades, or has ply separation then it can dump any fuel that is pump-pass-through or higher into your storage area (actually any fuel above the hose rupture point)

DR

Ordered hose today, I guess the oldest thing in fuel tank will be the pump in a week.

Now to figure out getting hoses out. I am guessing they all come out gas cap hole.

RF

January 25

1 hour ago, Redfoxx said:

DR

Ordered hose today, I guess the oldest thing in fuel tank will be the pump in a week.

Now to figure out getting hoses out. I am guessing they all come out gas cap hole.

RF

Afternoon RF

You can do it either way but either way TIE A STRING on each old hose (BEFORE removal) as that makes it a lot easier to PULL the new hoses back through rather than trying to work them through by pushing.

The white thing in the picture is a combination vent & roll-over valve.

January 25

1 hour ago, dirtrider said:

Afternoon RF

You can do it either way but either way TIE A STRING on each old hose (BEFORE removal) as that makes it a lot easier to PULL the new hoses back through rather than trying to work them through by pushing.

The white thing in the picture is a combination vent & roll-over valve.

DR

Thanks for the picture, Hoping the roll over valve is not brittle plastic. Should have parts next week, I can make sure the top drain isnt rusted up also. Tank sitting on bench rried out fuel tank Had to siphon out about the last gallon of fuel. cleaned out charcoal, a few pine needles, and looked like a little aluminum from some drilling, not sure on that one yet.

RD

January 25

7 minutes ago, Redfoxx said:

DR

Thanks for the picture, Hoping the roll over valve is not brittle plastic. Should have parts next week, I can make sure the top drain isnt rusted up also. Tank sitting on bench rried out fuel tank Had to siphon out about the last gallon of fuel. cleaned out charcoal, a few pine needles, and looked like a little aluminum from some drilling, not sure on that one yet.

Afternoon RF

"and looked like a little aluminum from some drilling" Look at the tank upper plastic mounting inserts, those tend to strip, or get cross threaded, so the threads get drilled deeper & rethreaded. Or ??? In any case make sure that none are drilled all the way through. If so then use some fuel proof thread sealer on the screw that goes into that hole.

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