I have a 96 r850r and what looks like brake fluid (but may be trans fluid) seems to be coming from the engine and dripping onto the large muffler/catalytic converter under the engine transmission. I noticed it burning off the muffler and no brake fluid leak found. The bike may have set up before the 2nd owner bought it. He put less than 300 miles then sold it to me. Does the transmission have a fluid level and could it be leaking near the clutch housing? What does the transmission fluid look like?
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trans fluid leak onto pre-muffler..?
- Thread starter heybiker
- Start date
ALIENHITCHHIKER
New member
The trans fluid is hypoid gear oil - the same stuff manual automotive transmissions are lubed with. It has a distinctive sulfurous smell to it. If the transmission output shaft seal is leaking it seems very likely that it could wind up on the premuffler. It could also contaminate your clutch.
deilenberger
A bozo on the bus
As Steve pointed out - tranny fluid has a very distinctive smell. It's also possible the rear-main seal on the engine is leaking.. that would result in engine oil, which doesn't have a distinctive smell.
In either case - the transmission is going to need removal to fix the leak..
In either case - the transmission is going to need removal to fix the leak..
AntonLargiader
Well-known member
If you have the 6mm allen head plug, it doesn't use a crush washer. You can create a leak by using one. If there's no centering taper for a washer on the plug, and there's a ridge on the sealing surface, no crush washer.
ALIENHITCHHIKER
New member
Thank you Anton - I have wondered about this !!! (Seriously)
Heybiker, stick your finger in the trany drain plug trough (when the bike is cold). If it comes out slick & stinky (hey -keep your mind out of the gutter) you'll know it's a leaky drain plug.
ANDYVH
New member
Fluid leaking onto the cat housing, if toward the front, could be the rear main seal on the crankshaft ahead of the inner pressure plate for the clutch (early oilheads were known for this, my 94 did it). Typically, this also creates a sludge line on the RH side where the tranny case meets the engine block. A leak of this type can also foul the clutch friction plate, as it did on my 94.
I suppose fluid from the front of the tranny, but not causing a sludge line on the engine case RH side, could be the tranny input shaft seal. A leak from there would have a distictive stinky smell, but I doubt ot would foul the clutch.
Fluid leaking onto the cat housing, if toward the back, could be the tranny output seal. Tranny fluid will have a distinctive stinky smell. If the tranny output shaft seal is leaking it cannot affect the clutch.
My guess is the rear main seal on the engine is leaking. The seal itself is inexpensive. Getting to it is not. I have pulled the tranny on my 94 four time and gotten it down to an eight hour job at home. A shop would change about four hours labor (our shop is $70/hour), plus parts and fluids. So you could be looking at about $350. But given the very low miles you might get an extension on the warranty with some luck and pleading.
I suppose fluid from the front of the tranny, but not causing a sludge line on the engine case RH side, could be the tranny input shaft seal. A leak from there would have a distictive stinky smell, but I doubt ot would foul the clutch.
Fluid leaking onto the cat housing, if toward the back, could be the tranny output seal. Tranny fluid will have a distinctive stinky smell. If the tranny output shaft seal is leaking it cannot affect the clutch.
My guess is the rear main seal on the engine is leaking. The seal itself is inexpensive. Getting to it is not. I have pulled the tranny on my 94 four time and gotten it down to an eight hour job at home. A shop would change about four hours labor (our shop is $70/hour), plus parts and fluids. So you could be looking at about $350. But given the very low miles you might get an extension on the warranty with some luck and pleading.
thanks for these tips..
I do think it has a distinctive smell. It has the color of brake fluid but the anti-lock has no leaks and no fluid loss noticed from either brake reservior. I have a Haynes manual to help locate the plug and remove the trans if I feel brave. I will note all the advice and look hard at this problem. The bike has 3600 miles and I was thinking it may have been stored and seals dried out. Is it impossible to hope the seal will reseat? Yes, the fluid is dripping on the front edge; but the oil window on the engine shows the oil a tan color. I asked the previous owner if he leaked brake fluid and he said no. The clutch seems to not slip and the fluid may be lessening its appearance. Is Charlotte, Charleston or Greenwood better for repair? Atlanta is my only other choice.
I do think it has a distinctive smell. It has the color of brake fluid but the anti-lock has no leaks and no fluid loss noticed from either brake reservior. I have a Haynes manual to help locate the plug and remove the trans if I feel brave. I will note all the advice and look hard at this problem. The bike has 3600 miles and I was thinking it may have been stored and seals dried out. Is it impossible to hope the seal will reseat? Yes, the fluid is dripping on the front edge; but the oil window on the engine shows the oil a tan color. I asked the previous owner if he leaked brake fluid and he said no. The clutch seems to not slip and the fluid may be lessening its appearance. Is Charlotte, Charleston or Greenwood better for repair? Atlanta is my only other choice.
1996 Oilhead models had this problem due to a manufacturing issue.....some sort of circlip gouged a seal mating surface on the input? shaft when installed, and tons of bikes had a gear oil leak. My wife's '96 R1100RS tranny got the seal fixed once, and then an eventual gearbox replacement.
ALIENHITCHHIKER
New member
Hope is always possible !
Indeed, that seems like a reasonable course of action. Put some miles on the bike, watch it closely and see what happens.
If you have determined the leaking substance is transmission oil, I'd start by changing it - I'd probably use BMW dino (not synthetic) since you're hoping to 'heal' the leak.
Hope is always possible.
overfill of trans fliud..
One item I noticed, when I checked the fluid level it was over the plug hole. The fliud was the same as the leaking fluid. I rechecked the manual to be sure I was looking at the right plug & "drained the excess". I know this may sound like a stupid and foolish move. The drain plug is below this plug but just not angled as the picture in the Haynes manual showed. I was going to test ride again because the leak shows after a few minutes of riding but the battery is weak. Just another thing I have to fix. I have to do things twice as much for this bike so we have decided to name it Trouble.
Let's see if it needs a battery. The previous owner gave me a BMW charger. I see where if fits in a outlet on the starter cover. I thought that was for a heated suit. Let's see what else this bike has in store for me.
One item I noticed, when I checked the fluid level it was over the plug hole. The fliud was the same as the leaking fluid. I rechecked the manual to be sure I was looking at the right plug & "drained the excess". I know this may sound like a stupid and foolish move. The drain plug is below this plug but just not angled as the picture in the Haynes manual showed. I was going to test ride again because the leak shows after a few minutes of riding but the battery is weak. Just another thing I have to fix. I have to do things twice as much for this bike so we have decided to name it Trouble.
Let's see if it needs a battery. The previous owner gave me a BMW charger. I see where if fits in a outlet on the starter cover. I thought that was for a heated suit. Let's see what else this bike has in store for me.
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