Oil leak!

[Padre4art]

Good morning - I have just discovered a oil puddle of about 3 inches diameter under the oil sump of my new (old) bike, 1979 XS11F. It's too far back to be the oil filter, I think. Can the oil sump (pan) leak with age?

I am wondering if the bolts may be loose or if it needs a new gasket.

Also wondering if the pan can be removed and replaced with the engine in the bike?

Anyone who has been down this road - comments appreciated!

Art in Chambersburg PA where it is getting too COLD to ride!

[leggman1]

The oil pan can be removed / replaced with the engine in the frame. I would clean it all good first and see where the leak is coming from. It could just be a loose oil filter bolt.
Dave

[Padre4art]

re: Oil Leak

Thank you - will look more closely this weekend!

Art

[motoman]

Possibly damaged, compressed filter can O-ring from extensive heat. Replacing the filter can O-ring may resolve the leak issue.

[TopCatGr58]

Hey Padre,

Did you ever download the user/service manuals from the link I gave you in your membership confirmation?

Aside from the main oil pan that CAN leak when the gasket gets loose with loosened bolts, there's also the MIDDLE drive drain plug just behind the end of the pan under the engine. So you'll want to ensure that the oil you found is regular oil vs. hypoid oil. Wouldn't hurt to check your middle drive to make sure it's got enough oil in it. Folks have reported incidences about the middle drive accidentally running dry and then locking up while running down the highway!

You may have to remove or move the exhaust/muffler to be able to access some of the pan bolts along the sides. If you do take it off, you can use Threebond/Yamabond alone without a gasket to seal it.

T.C.

[Padre4art]

Thanks guys -

I think what I may have is a defective crush washer under the drain bolt on the oil pan. Surprising with only 722 miles on the bike, but maybe its been on and off a few times in 37 years!

Will get a new one and try that!

[Padre4art]

RE:Manual

I was able to download about half the manual before some glitch occurred! Thanks for the link!

Since then, I have ordered a used manual from eBay. I also ordered Bob Jones book through Amazon (apparently from his widow.) I think you can get one directly from her through this forum as well - missed out on that opportunity!

Art

[motoman]

Thanks guys -

I think what I may have is a defective crush washer under the drain bolt on the oil pan. Surprising with only 722 miles on the bike, but maybe its been on and off a few times in 37 years!

Will get a new one and try that!

Originally, pan drain bolt had a thin-thin stainless washer on it. A good replacement is a copper washer that I.D. fits snugly around threads of drain bolt.

[Padre4art]

Mine has a fairly thick aluminum washer, probably no good!

[MaximPhil]

Mine has a fairly thick aluminum washer, probably no good!

Hi Padre4art, be very careful tightening the drain plug it is easy to strip the threads
Phil

[Padre4art]

I may have found the culprit. Hope so. The bike was shipped from California to Pennsylvania in a truck. It has smelled like old gas since arrival. I think the gas was dripping out of the bottom of the air filter housing and winding up under the engine.

Today I pulled the air filter. There was several tablespoons of gas in the lower housing. Also when I changed the oil it was like water, gas mixed in.

I am going to watch this closely. Thanks for helpful advice!

[motoman]

I may have found the culprit. Hope so. The bike was shipped from California to Pennsylvania in a truck. It has smelled like old gas since arrival. I think the gas was dripping out of the bottom of the air filter housing and winding up under the engine.

Today I pulled the air filter. There was several tablespoons of gas in the lower housing. Also when I changed the oil it was like water, gas mixed in.

I am going to watch this closely. Thanks for helpful advice!

To solve that issue, likely need to replace float needles/seats and remove petcocks from tank, take apart and clean internals.

[Padre4art]

Thanks. I have pulled the petcocks. One leaks. Have ordered rebuild kits. Bike runs perfect so I am reluctant to tamper with the carbs right now.

[Ken Talbot]

If there was fuel in the bottom of the air cleaner, it was getting past a defective petcock _and_ a defective float valve. If either one was working properly, there would have been no leak.