[pauhig]

My T100 has a small oil leak on the right side of the head..between the barrel and the rocker cover...could be coming from a pinhole in the head casting......any ideas??

 

[Bryan]

Are you sure your valve cover gasket isn't leaking? It could be draining down into the spark plug well and then coming through the cooling fins.

 

[wenzel850]

My T100 has had a similar "leak" for 4 years and hasn't gotten any bigger or leaked more. I think it may have been some cosmoline that the dealer never cleaned off completely.

 

[Baltobonneville]

If your bike is new, it could well be the cosmoline. Thorough cleaning and time would take care of that.

The cam cover gasket is the next most likely cause. This happens to (too) many of these bikes, probably a combination of poor design and less than perfect assembly at the factory. Luckily, it's also easily fixed, and is covered under warranty.

Another simple possibility is leaking banjo bolts at the oil cooler line connections, also easily fixed.

A few people have had leaks in worse places, one or two have had porous castings in the engine, but that is unusual.

I'd clean the entire upper engine area thoroughly and try to determine where it's coming from, or even if it comes back. Remember that oil can blow back and wind up in unlikely places that are not near the source of leakage.

Some people have mentioned a UV dye that you can put in the oil to help trace leaks, which might be helpful if you decide it's not the cosmoline.

 

[bheezy27403]

I have a '08 T-100 with about 3600 mi on it and have developed the exact same leak. Like mentioned earlier I beleive it is leaking from the cam cover and is running behind the spark plug before blowing out the fins. Taking it in in a couple of weeks to get it fixed and its covered under the warranty so no big deal. Just have your people look at it. I'm also getting my AI yanked out and having my Emgo reverse cones put on! This will be the only time I will ever be excited about taking it to the shop for an oil leak!

 

[Geimer]

Ditto on the oil coming from cam cover, down by the spark plug and out through the opening in the cooling fins.
My initial fix: tighten the cam cover screws (not too much, they have a light (10nm) torque setting) because mine were dead loose. I mean looser than finger tight when I found my leak and checked.
Later, at my 12000 mile valve clearance check, I added a thin line of RTV sealant to the valve cover gasket and the leak is completely gone.

But, as was mentioned earlier, it may be leftover cosmoline on a brand new engine. So cleaning it would be prudent.

Good luck

 

[mightydaj]

I know this is a little late but I was having the same problem and thought I would post a fix that worked. Mine started leaking at around 6000 miles and was very small at first. It got very slowly worse until by 10500 miles it was too bad to ignore. It was leaving a mist of oil on everything behind the motor and oil level down a bit after every ride. I was hoping to make it to 12000 miles when the cam cover has to come off anyway, but I couldn't put it off anymore.
What I did was clean the cam cover very good. This was slow and used a lot of Q-tips to get all of the baked on oil out of the groove in the cam cover. I also cleaned the rubber gasket very well and also and the top of the head. When the cam cover was dry I ran a thin bead of red high temp silicone sealer around the entire groove on the cam cover and put the rubber gasket in it. I turned the cover right side up on a flat surface with some weight on it and let it sit for a few hours. I wanted the gasket to bond with the cover and have the silicone increase the thickness a bit. If it was put on immediatly the silicone would get squeezed out tightening the cover.
In a post someone had said that the rubber seals of the cam cover fastner screws get "flattened" and don't have enough thickness before the screws bottom out where they seat into, to press the rubber cover gasket tight enough. This looked like this happened to my bike. I got 4 3/8" washers from the hardware store. The OD was just a tad bigger than the screw but still had plenty of clearance with the sides of the cover well. The ID was just a bit too small to allow the screw body to pass through. I drilled them out to the right size to just pass the screws. After a few hours I carefully mounted the cover on the head. I wiped the gasket and head off again by tipping it up on each side after getting it back in place as another poster had said that it should be completly dry and I couldn't get it back on without touching some of the cam parts which were still oily. I put the screws with the added washers back on and torked them to the specks (about 8 ft/lbs). With the washers in place the screws did not bottom out and I got a good seal. There have been no leaks since then.

 

[Baltobonneville]

:goodpost:

 

[Santacruiser]

Great detail

I have the same problem...excellent post. Thanks, I'm on it now