fix oil leak without new gasket

[marp68]

I got a tip from a mechanic when I mentioned the small leak in the front of the cases. He recommended me to check the breathing tube, if it was clogged, etc, so that the breathing wasn't working propely.

 

[marp68]

Btw,
where does the breather tube leads after going down into the left hand engine cover?

 

[grizld1]

The hardest part of the split job is finding the torque sequence numbers cast into the cases. The numbers are in assembly sequence, so when you're separating the cases, start with the high numbers (fasteners on the upper case half) first. If there are a few numbers you can't find, it's not a major problem--just be sure to relieve and apply torque in small increments, working opposite-to-opposite, outside-to-inside during breakdown, inside-to-outside during assembly.

 

[xjwmx]

Is it difficult to break the cases apart once unscrewed and get the old sealer off the surfaces? Are there recommended methods and tools?

 

[XSLeo]

Here's a guide to case bolt numbering.

 

[grizld1]

Re. breaking cases apart--it's an easy job, takes at most a few smacks with a rubber mallet. Surface prep is simple as well, paint on gasket remover or strong paint stripper with a brush and scrape off with light pressure, same as you would any other sealing surface.

 

[XSLeo]

If your breather is restricted or plugged tight, as the pistons com down , pressure builds up in the crankcase. If there is a spot where a seal or gasket is weak this pressure can push oil out through the weak spot.
As the pistons come up a vaccum is created which holds the oil from going out the weak spots.
A brake booster valve is a one way vaccum valve. As the pistons goe down the pressure build up pushes air out the breather but wont let air back in. This extra vaccum helps keep oil in and helps the rings seal to the cylinder walls.
On the stock breather. as the pistons move up and down the air can move in and out of the engine through the breather. This air has some oil mist mixed in with it. This oil mist is from the moving parts inside the engine. The oilmist that gets pushed out the breather tends to collect on the inside of the hose. The oil as it collects runs down the hose. They put the hose in a hole above the drive chain. THe oil drips on the chain. It helps lube the chain, makes more of a mess than helps lube the chain.

 

[marp68]

The breather tube is okej, not clogged, just stiff, so I will change it anyway.

Regarding the leak, I was thinking about buying this loctite mass/clay that one can form and apply to seal/tight/build with. But it is hardening, so I'm a bit skeptic since the engine is vibrating pretty much. Would it be a better idea to use something more flexible, like silicone?

Flexible or hardened/stiff is the question...

/M

 

[gmiller217]

if you are looking for a temporary repair, there is some stuff called seal all ... not sure if you can find it in Sweden though. If you can score a tube you can clean all the old silicone off the cases with a wire brush and gasket scraper (hand held brush not power) spray it off with brake cleaner then apply the seal all. I have used it before on gas tanks and such. The first time I used it was on a lawn mower tank that I couldn't buy and it had a pin hole leak. The repair lasted for five more years then my father sold the mower.

 

[marp68]

Googled on it, and it seems great. I've read about similar things, so that's probably what I end up using. Normal silicone is to flexibile I think, since there there will be some pressure on it.

Thanks