Getting at my problematic oil leak

[hotspot]

Hi Everyone,

 

I have a very active oil leak (only takes a few miles to get it running down the sides of the transmission case and eventually onto the catalytic converter). It's coming from up high and I think it's possibly coming from the breather that is on the back top of the engine from what I can see on diagrams. The problem is that I can't see where it's coming from, or get at it to fix it because the airbox is in the way. And I simply can't see a way of getting the airbox out of the way apart from taking out the brake control unit and maybe more stuff besides that:( This looks like not such a good idea what with bleeding issues and all.

 

Can any of you help me with this issue?

 

Thanks,

 

Dave

[AndyS]

Is the oil Engine Oil or Gearbox Oil?

[upflying]

Start with the easy stuff. Is or was the engine oil overfilled and is there oil on the bottom of the air filter box?

[AndyS]

And by the bottom of the Air Filter box, bob means right at the bottom. There is a sump below the air filter and if there has been an overfill, this is where the engine spews the excess oil. If there is oil in there, there is a drain screw in the very rearmost left hand corner of the box, accessible from behind the left hand side panel

[dirtrider]

Morning Dave

 

As Andy mentioned , start with a check of the air box breather drain (see picture below).

 

Otherwise your problem could be anything from a leaking vent hose, to some sort of engine seal leak, to the engine temp sensor leaking, to engine gasket, to ????.

 

If it smells like gear oil then maybe blowing out the trans vent on top of the transmission.

 

MAKE SURE the engine isn't overfilled with oil as that can allow excess oil to find a way out.

 

When did your oil problem start? If after a service or after adding oil then maybe overfilled.

 

[hotspot]

Thanks for your responses!

 

Here are the answers:

1. It started after being run quite a while accidentally overfilled when I first got the bike.

2. There was oil in the airbox. I drained it out, cleaned the box with compressed air as best I could. I cleaned the oil off everything with the plastics off. Then rain it, and the leak is still there, and it only takes 10-20 miles to have more oil actively leaking off the top of the tranny (at least that's where I think it's from since I can't tell because of the airbox).

3. The engine is not overfilled now, and so that is not the cause of the ongoing leak, though it probably got the leak started.

4. I saw the vent hose on a diagram, and it looks like it might be in the right location to cause this.

5. I can't tell if it's tranny fluid or oil. How does one do so?

 

Thanks,

 

Dave

[AndyS]

Engine Oil and Transmission oil smell TOTALLY different.

If you smell the oil and compare it with the smell from the engine oil filler cap it should be pretty clear. However do you have any transmission oil in a container? compare the smell and you will see.

[Joe Frickin' Friday]

Engine Oil and Transmission oil smell TOTALLY different.

If you smell the oil and compare it with the smell from the engine oil filler cap it should be pretty clear. However do you have any transmission oil in a container? compare the smell and you will see.

 

Just to avoid confusion, "transmission oil" sounds a lot like automatic transmission fluid, which

 

A) has its own smelll, and

B) wouldn't be found on an RT.

 

If the OP has some of this on his garage shelf, he should be careful not to confuse this with the fluids involved in his current problem, which are engine oil and gear oil (sometimes called gear lube). Those two do indeed smell completely different from one another; if the OP has some gear oil, he should take a whiff of that and compare it to whatever is leaking out of his bike. Gear oil/lube is what gets used in the bike's transmission and final drive.

[Dave Parry]

I changed the battery on my R1100RT recently so as the left side panel was off I thought i'd check this oil drain that I've read about and I couldn't find it! Do some 1100RT's not have it or didn't I look hard enough? I must admit all I really wanted to do was get it all back together,

 

Dave.

[dirtrider]

 

Afternoon Dave

 

We probably should know what you are working on so we get you the correct data.

 

On telling gear oil from motor oil--Maybe.

 

Most (but not all) gear oil has a very high sulfur content so if your gear oil is the sulfur containing type it will have a very distinct sulfur smell to it.

 

Some trans gear oils look a lot like auto trans fluid & have very little sulfur smell to it.

 

Others look & smell a lot like motor oil.

 

If your engine was overfilled possibly your trans was also. If the trans is/was overfilled it could be spitting the oil out of the trans vent (see picture below).

 

Will it leak running in place or do you actually have to ride it? If you have to ride it that might point more towards the transmission.

 

[philbytx]

Cut Andy some slack Mitch...he's a Limey fer gawd's sake !

 

LOL

 

[hotspot]

I believe my transmission is overfilled. I will drain some off as soon as I can. I'm wondering about how it is possible to overfill it, since you are supposed to fill it to the bottom of the fill hole. How can it be filled up further than that since that would seem to be the highest point available during a fill up? Anyway, it is higher than that, but how it could be I can't understand.

 

Dave

[hotspot]

Also, once the transmission breather kicks some fluid out, is it "breached" such that it won't reseal when the level is reduced?

 

Thanks for the picture of the top of the tranny. Based on where the oil is leaking down, I think the vent is a very likely leak point.

 

Dave

 

[VoipWizard]

I have seen some trannies being overfilled when filled up with the bike on the side stand instead of the center stand. Just a thought.

 

[hotspot]

That makes sense to me...

[drtnsnw]

I am keeping a close eye on this one. I have the same problem and was pretty sure I had a shock that was leaking onto the pipe right at the cat. I am not so sure now but until I pull the shock off and look carefully I can't tell.

 

I also had some oil in my airbox that I drained out. With the air filter off I can see a film underneath it but not like it is sloshing around in there.

 

If I find anything, I will post up here too

 

Chris

[AndyS]

:dopeslap:Thanks for defending me Phil!

I say Aluminium you say Aluminum.

I say Gearbox, you say Transmission.

I try to translate gearbox oil into American and say Transmission oil....and get told off.

So Tyres, Bumper, Boot, Mudguard! There, I've done it again...got the translation incorrect!

Seriously though, sorry if my comment about 'transmission' oil caused confusion. Feel free to correct me.

[hotspot]

Hey Andy,

 

I'll never forget when we were living in Africa and our Ghanaian (former British colony) house boy was told to iron my pants and thought we were talking about underwear. He couldn't process the idea of ironing underwear until he realized that WE were talking about what he called "trousers."

 

Anyway, just a note- there was a drop of fresh oil on the bottom of my rear shock when I examined things a few days ago. But I'm pretty sure it was just oil blowing back on the shock from further forward.

 

By the way, I know very clearly the difference in smell between automatic transmission fluid and motor oil. What I'm not so sure about is hypoid gear oil vs. engine oil. But I'll figure it out:)

 

Dave

[AndyS]

Hi Dave

The smell difference between engine oil and gearbox oil (hypoid)is very pronounced. Hypoid oil STINKS and it clings - inasmuch as you may wash your hands, but the smell sticks around!

Nice story about the ironed pants!

[hotspot]

So does anyone know the answer to my question about whether the breather will reseal itself once the level of the tranny fluid is at a proper level?

 

Dave

[dirtrider]

So does anyone know the answer to my question about whether the breather will reseal itself once the level of the tranny fluid is at a proper level?

 

Morning Dave

 

It's vent so there is nothing to be re-sealed. It allows the heated air inside the trans to escape as the trans heats up then allows makeup air back in as the trans cools.

 

If you seal it then the trans will blow gear oil out the shaft seals as the trans heats up inside.

 

[hotspot]

Thanks D.R.

[hotspot]

Hi Everyone,

 

I haven't been riding because we've had a very cold streak and snow on the ground. I'll let you know more about whether the leak is better once I've had a chance to do some more riding and monitor what is happening with it,

 

Dave

[drtnsnw]

Hi Everyone,

 

I haven't been riding because we've had a very cold streak and snow on the ground. I'll let you know more about whether the leak is better once I've had a chance to do some more riding and monitor what is happening with it,

 

Dave

 

Man, ain't that the truth!! It has been so cold here in Reno I can't even work in the garage!! pretty fricken bad!!

 

Chris

[Twinsig]

Real cold in dixie too.

I'm gonna call Al Gore and ask him to fly around middle Alabama, it's freezing!

[drtnsnw]

Real cold in dixie too.

I'm gonna call Al Gore and ask him to fly around middle Alabama, it's freezing!

 

Yeah, my sister lives in East texas. She called my wife and asked her to send snow boots to my 2 nieces because they can't find any!!

 

BTW, it has been below 0 every night the last week here!! If it gets into the teens I am going to ride (probably the KLR)

 

Chris

[RobinW]

I had a leak on an R1100RS I could not identify. I found it by revving the engine while on the centerstand. It was coming from the oil cooler return pipe. Only showed up when oil pressure/temperature where up.

 

Not saying that's your issue, but make it hot and rev it up and look again.