Husqvarna 450 rebuild, issue with crank bearing and seal.

[Fordiesel69]

No dice, ran 1 minute, and now an air leak on the side of the case with the crack.

So before I buy a new plastic crank case, do you think the cylinder may also be bad?

 

[spasm3]

No dice, ran 1 minute, and now an air leak on the side of the case with the crack.

So before I buy a new plastic crank case, do you think the cylinder may also be bad?

Pics? how does it look? Maybe clean it with hydrochloric acid.

 

[Fordiesel69]

Perfect, I ,meant the bearing "sqeeze" maybe that is why it is leaking. Where the cylinder base meets the plastic crankcase.

 

[Fordiesel69]

A guy that did a Poulan PP4018 on youtube used moto seal and his crank case leaked like a sieve. He then got permatex optimim black max flex sealant and it worked like a charm.

Shall I buy another crankcase or try to reseal again with this black. With reading about motoseal, it appears it is only for small .002" gaps and for metal to metal contacts.

 

[Cujet]

Perfect, I ,meant the bearing "sqeeze" maybe that is why it is leaking. Where the cylinder base meets the plastic crankcase.

Maybe the dimples space things out a bit. I'd clean them up if they cause too much space and result in a leak.

 

[Fordiesel69]

Fingers crossed 4th time may be a charm. I put the moto seal on a drawer as I found out from a Honda mechanic it's for metal to metal and not more than 6 thousands of fill, 2 thou is more optimal. I now re did it with pernatex optimum black and need to wait till tomorrow morning to find out I'd it will seal.....

 

[Fordiesel69]

Video!

Chain is super dull, but I think the engine runs pretty nice as is. I used Permatex Optimium Max Flex in addition to the factory o rings for the cylinder. Seems to be holding. How does it sound to you guys?

 

[tnt_motorsports]

It sounds ok. Is your oil mix right? My Stihl doesn’t smoke like that so it’s either heavy on oil or a bit rich. Mine tends to 4 stroke on me at WOT as well. Yours didn’t but you didn’t keep it there for long and I’m not sure how warmed up it was. Put on a new chain and let it eat. Adjust the carb if needed.

Just my $0.02

 

[Fordiesel69]

Its a bulk mix of red armor 50:1 with a little dab extra as i did put a new ring on the piston and deglazed the cylinder. I like to run a few tanks rich so it wont score up......

I honestly like chainsaws a little heavy on oil. However that smoke is from the $9 dollar ebay muffler as mine was not included and missing from prior owner.

 

[Fordiesel69]

Lastly, how long would I need to run it (tanks of gas) before I will know if the Permatex Optimum Max Flex RTV will last? I know the crankcase will have air / oil / fuel mix in contact with the sealer, but as long as the liquid fuel does not lay in the crankcase, will this be ok long term, or will it need to be resealed every season?

 

[jeepman3071]

It should be fine, I assume that stuff is fuel resistant?

 

[Cujet]

Lastly, how long would I need to run it (tanks of gas) before I will know if the Permatex Optimum Max Flex RTV will last? I know the crankcase will have air / oil / fuel mix in contact with the sealer, but as long as the liquid fuel does not lay in the crankcase, will this be ok long term, or will it need to be resealed every season?

RTV is never the right choice for gasoline. However, it may hold up, as RTV just becomes soft in gas, it may remain in place just fine. Just run it and see.