Engine Trouble Crankshaft seal replacement every 3 months

[LunchMoney]

Greetings, as the title states, my crankshaft seal behind the magneto goes bad every few months. Unfortunately, i have only acess to cheap chinese crap parts, as well as chinese seals. Any recommendations to fixing this seal problem? Maybe replacing the seal and smudging some rtv silicone?

 

[Johnny_]

Greetings, as the title states, my crankshaft seal behind the magneto goes bad every few months. Unfortunately, i have only acess to cheap chinese crap parts, as well as chinese seals. Any recommendations to fixing this seal problem? Maybe replacing the seal and smudging some rtv silicone?

I'm assuming it goes bad where it seals around the shaft? If you're not, pre-lubricate the seal with grease, otherwise it will go bad very quickly, like you are experiencing.

 

[LunchMoney]

I'm assuming it goes bad where it seals around the shaft? If you're not, pre-lubricate the seal with grease, otherwise it will go bad very quickly, like you are experiencing.

Yes, the shaft. I pre-lubricate it, and it goes in smoothly. Should i put more grease?

 

[Johnny_]

Yes, the shaft. I pre-lubricate it, and it goes in smoothly. Should i put more grease?

Maybe try that, grease both where it seats into the case, and where it goes around the shaft. A little too much grease isn't gonna hurt.

Also, I can't exactly recall what the keyway is like on these engines, but I know on engines I've worked on in the past I've put some masking tape around the shaft to make sure the sharp edges didn't cut the seal. If the edges are sharp and it's wide enough to cut the seal, maybe try that?

 

[LunchMoney]

I don't see anything that is sharp enough, and the old seal looks fine. I think the main problem is that the seal gets rock hard and it does not seal anymore, it get smaller

 

[DAMIEN1307]

the main problem is that the seal gets rock hard and it does not seal anymore, it get smaller

That is usually caused by the ethanol found in most petrol/gasoline because the Chinese seals are not Viton seals that would be resistant to the ethanol to a degree.

You need to see if you can find ethanol-free gasoline in your area, usually a boating marina or small private aircraft airport usually has ethanol-free availabele since many boat motors and small aircraft require it.

 

[Gordy]

Is the crank true?

 

[LunchMoney]

That is usually caused by the ethanol found in most petrol/gasoline because the Chinese seals are not Viton seals that would be resistant to the ethanol to a degree.

You need to see if you can find ethanol-free gasoline in your area, usually a boating marina or small private aircraft airport usually has ethanol-free availabele since many boat motors and small aircraft require it.

The most i can find is e85, i really don't think i can get my hands on some non-ethanol fuel, maybe if i was living in suburbs, but i am in the middle of the city

 

[LunchMoney]

Is the crank true?

I have no idea, does that require splitting my case?

 

[Johnny_]

I have no idea, does that require splitting my case?

Yeah. And a lathe, and some other tools.