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Getting fuel tank full


Reddogracing

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Barring some strange mod, yes.

 

Run it down, drain it (Harbor Freight sells cheap hand powered siphon that will make that easier.

When empty, add measured gallon, reset odo, go fill up.

It will hold more than a few gallons.

What year?

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Reddogracing

2004. I was able once to get another gallon in it by filling the next and letting it settle. Did they leave all that space at they'll of the tank for a reason.

 

I will try that. Now that it is running better I hope it gets better mpg it was crap I went 180 miles started full. Filled up once in the trip and once after. Do not remember how many gallons it took once it was like 4

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2004. I was able once to get another gallon in it by filling the next and letting it settle. Did they leave all that space at they'll of the tank for a reason.

 

I will try that. Now that it is running better I hope it gets better mpg it was crap I went 180 miles started full. Filled up once in the trip and once after. Do not remember how many gallons it took once it was like 4

 

Morning Reddogracing

 

Yes, that is expansion space for your emission control system so a tank just filled with fuel, then left out in the hot sun, won't spit raw fuel into the evap canister system.

 

In the old days we use to drill (or punch) a hole in the top of that fuel neck restrictor so we could more easily fill the tank all the the way to the top. This would ONLY be used just prior to a long trip so the fuel would be used out of the tank before it could expand & fill the evap system.

 

If your evap can has been removed then you can (drill/punch) a hole in the top of that restrictor insert but then have to be careful to not overfill the tank then park the bike is a hot garage or you risk having raw gasoline flowing out of the tank vent & filling you garage with explosive gasoline fumes.

 

 

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+1 on DR's comment. I have done this years ago. I originally popped a 3mm hole in the side (very near the top, and on the RHS of the neck). This made life so much easier for getting a lot of extra fuel in for an immediate start on a long ride. However, recently I opened that hole up to 6mm and it has made the fueling process much better because the hole allows the displaced air to escape much more quickly.

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+1If your evap can has been removed then you can (drill/punch) a hole in the top of that restrictor insert but then have to be careful to not overfill the tank then park the bike is a hot garage or you risk having raw gasoline flowing out of the tank vent & filling you garage with explosive gasoline fumes

 

Dirt Rider... Speaking of this, I have seen a couple of You-Tube videos that recommend removing the evaporator activated charcoal can and just re-route the hose to the bottom of the bike and block off the vacuum hose to prevent carbon recessing into the fuel filter or blocking flow of air in the hose leads causing a tank collapse or fuel sender mis-read due to obstruction. What's your take on the can ....leave it on or removal??

 

I also get a not quite full indication on the fuel sender (1 bar less than full) but this could be equally due to a soaked float or just the sender (mine is resistance not capacitance model) being worn so the number of ohms registered doesn't change near the top.

 

I always set my trip ODO to zero on each fill-up. I know I have 240 miles guaranteed before the reserve light comes on regardless of the fuel level indicated.

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Afternoon Rx_Mich

 

It's illegal to remove or tamper with vehicles emission controls so my official take is to not remove it.

 

But if you have an evap can that is blocked then there is a good chance that the plastic tank sides will suck in & crush the fuel sender tube as the fuel is used out of the tank. (the crushed tube prevents the float from sliding up or down inside the tube)

 

As for your gauge not reading full on a full tank?-- There are a number of BMW service bulletins on this problem.

 

Terminal resistance in the connectors is always a possibility but the usual cause of fuel gauge reading errors is ground (low side) resistance in the pump/gauge grounding. Unfortunately the old BMW boxers use the same ground connections & ground path for both the electric fuel pump & fuel gauge so pump load can cause gauge grounding errors.

 

A good place to start is to clean ALL the pump connector terminals, if that doesn't cure the gauge error then refer to one of the BMW bulletins & run a separate ground wire from pump pass-through back to battery (-) post.

 

I have seen some of the old boxer bikes that the solder in the pump pass through grounding is degraded & a separate ground has to be made & added to the fuel pump pass-through plate to totally cure fuel gauge reading errors.

 

Added: regardless of what you do with your evap can you should cut the bottom the vent hose (it exits behind the R/H rider foot peg) with a 45° cut to prevent the vent hose from sucking road water into you evap can or fuel tank.

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Thanks for your input. Mine has always worked ok. Maybe the problem is with later models. Once I get inside of the tank and replace everything I can make a better decision on it's existing function after opening up the fuel filter and inspecting its contents on the engine side (clean side) of the filter. If I am seeing any charcoal then I will take it from there. Don't know why they wouldn't have a micro mesh screen in there to keep the charcoal in the canister... but hey, I didn't design it. :)

 

My other reason for mentioning it is that it could be a possible reason someone isn't getting a full tank indication on their fuel gauge if that capacitance tube has been damaged. Not going to be easily seen just looking in the tank with a flash light. A good clue would be unlocking the fuel tank and you hear a whoosh of air equilibrating the pressure that a blockage is happening.

 

Pump kit and hoses came in today from the Boneyard. Still waiting on 5mm vent hoses. I opted for the after market pump kit.... seems a better design with the pump port made of brass in lieu of plastic (OEM). Anyhow, it has the blade connections so all that will be new metal on the inside. I will look at the outside ground lead and make sure it is clean. If the connector is crappy, I will cut and replace with fresh ring terminal....possibly a larger ground lead would help with conductance too. I will make a fresh Tefzel insulated wire run to the battery ground terminal. The wire I use it Teflon insulated so good to 200 degrees C and it is all Silver plated Copper. There is very little line loss.

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Morning Rx_Mich

 

Sounds like a good plan--

 

As long as you will have the pass-through removed you might also:

 

Measure the resistance on the brown wires on the inside of the tank vs the outside of the tank (mainly in the solder joint of the wire pass through).

 

Also, CAREFULLY inspect the in-tank wiring for signs of degradation & insulation cracking. Some fuel additives & alcohol in the fuel can degrade the in-tank wire insulation.

 

I doubt you will find any carbon from the evap system in the fuel tank but could find some in the evap system engine side purge hoses or in the evap purge valve.

 

The whooshing at fuel cap open is a giveaway that the evap system is plugged or plugging BUT if all your riding trips are short then you might not get the whooshing even with a plugged evap system.

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+1If your evap can has been removed then you can (drill/punch) a hole in the top of that restrictor insert but then have to be careful to not overfill the tank then park the bike is a hot garage or you risk having raw gasoline flowing out of the tank vent & filling you garage with explosive gasoline fumes

 

Dirt Rider... Speaking of this, I have seen a couple of You-Tube videos that recommend removing the evaporator activated charcoal can and just re-route the hose to the bottom of the bike and block off the vacuum hose to prevent carbon recessing into the fuel filter or blocking flow of air...

 

One good indication of a blocked or marginally blocked canister/hose is vacuum inside the gas tank manifested by some resistance when trying to open the filler cap. It makes a distinct suction sound.

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Whats the best and safest way to put a hole in the fuel neck restrictor?

 

Afternoon PAS

 

Safest way is to remove filler neck from tank then drill the hole with filler neck away from tank & fuel.

 

Some have punched a hole with filler neck still in the thank (leaves a crude looking hole & not the safest but is seems to work)

 

 

 

 

 

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For the R1150RT you can replace the entire fuel filler neck with a unit off of an R1100RT including little plastic goodie that prevents fuel from flowing out the vent line. The neck is shorter and allows more fuel to be onboard while still allowing room for expansion.

 

Stan

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Just an update on the fuel pump hoses and replacement. Fuel filter hoses both afferent and efferent were still serviceable but still soft walls. Fuel filter date of last installation was 2002. Fuel pump hose was original from 1996 and was soft and leaking. Vibration damper was very hard and not doing its intended job.

 

Fuel pump and hoses

 

I still need to rewire it and will use the supplied wiring back to the soldered pass through. All-in-all the Boneyard kit is straight-forward and they give you the updated clamps that can be screwed tight in place of crimping. The new hoses look like they will be impervious to ethanol fuels and a nice tight fit even before the clamps.

 

Also have not yet installed the pre-filter. I will do that just before buttoning the whole thing back up. They give you new O-rings for the fuel sender and the top of the tank. I will coat them with Fuel-Lube prior to assembly. It is impervious to gasoline and oil and keeps the O-rings plyable....does not degrade Vyton rings either. This takes care of the 4th of 1 of 4 "I gotcha stranded" scenarios. Vent hoses yet to arrive but I expect them tomorrow. Should be ready for a weekend ride. :)

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Hi jmann,

There isn't much in it, but you can probably get it fuller using the side stand.

There has been much talk about this, and the very fact that there has, reinforces the fact that it is a very close run thing.

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