Weeping base gasket

The bike has 10,600 miles, with about 1,800 put on since mid August. The base gasket has started to weep in a few places, on the backside by cylinder 3-4. I changed the oil about 250 miles ago, and ran a few ounces of Seafoam in it for 20 miles before I changed it. The intent was loosening any sludge before the oil change.. It has straight 10w-40 now.

I'm wondering if thinning it is the reason for it weeping, even though it was for only 20 miles?

The order you typed in what you did said:

weep
seafoam treatment
20 miles operating with seafoam

First, was it weeping before you put the Seafoam in? I have never heard of Seafoam causing a weep or a gasket to leak. For oil to get past a base gasket, it has to find a way through or around a pretty heavy piece of gasket material. Seafoam is a petroleum distillate and I doubt it would bother an engine gasket.

I have used the stuff many times and never noted this problem... Twenty miles using the stuff? Hmmm I wouldn't think so but it might be worth the effort to find out if you can contact whoever makes Seafoam and talk with their tech or customer support folks...

It made sense to me.. :blush:

In the proper order now..

I added the Seafoam and drove 20 miles, then changed oil to 10w-40. 250 miles later there is 2-3 small spots below the base gasket. I don't think it's really the problem, but I was asking.

What about this?

I took this compression reading 2000 miles ago, engine cold, WFO throttle.
#3 compression being 130, the others were closer to 145-150. Maybe this is the reason, extra pressure getting into the crankcase, and finding these small weak spots?

Try a retorque on the head nuts, while the engine is warm, 25-30 ft/pounds I think...

1045

The compression problem may be the result of the base gasket leak... can't say. I would check the torque spec and retorque the stud nuts as suggested and do it in the pattern that is recommended in a shop manual.

I would still contact the Seafoam manufacturer as there seems to be little else that would or could have caused the problem. See what they have to say. Can't tell, they might be helpful. They probably know their stuff better than us.

I got an answer from Seafoam,


"SeaFoam is a 100 % oil product, so can cause no more harm than the oil you use in your cycle, ie: SeaFoam can not do any damage to gaskets, o-rings, seals, etc.

SeaFoam is a high detergent cleaner, lube and moisture drier when used in the crankcase, also you have seen what advantages there are using it in the fuel. Remember, one ounce per gallon of fuel will keep your fuel good for two years, make sure you run the bike so your entire fuel system is protected!

Thank You!

Customer Service"

:side: