Crank seal Oil In cover do I need to worry ??

steve-uk

Manners cost nothing
Location
Barrie - ontario
Engine was built in April 09 and was only run between April & finals Havasu...

so half a season I guess...

The way this one looks I am quite confident it needs to be replaced...

I have that pump and some rubber stuff for leak down, does it require the pistons to be in certain position ? Or just block intake and exhaust manifold and pressurize thru pulse line, both line or one puls fine and block the other one ?

And 9 seems high, is that just for a quick test and then another 6 for like 10 mins or so .?? I havent done one in so so long

if you have that going on with the front one you may want to check the rear....

did you hydro lock the ski maybe? good way of blowing out a crank seal, i changed mine in sept last year and hydro locked at wavedazes, rears need replacing now... rears blow out easier than front...
 

QuickMick

API 1104 AWS CWI
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Engine was built in April 09 and was only run between April & finals Havasu...

so half a season I guess...

The way this one looks I am quite confident it needs to be replaced...

I have that pump and some rubber stuff for leak down, does it require the pistons to be in certain position ? Or just block intake and exhaust manifold and pressurize thru pulse line, both line or one puls fine and block the other one ?

And 9 seems high, is that just for a quick test and then another 6 for like 10 mins or so .?? I havent done one in so so long


ok go 6-7 then, but I have heard to go 9. If your have two pulse lines, put your pressure gauge on one pulse line and the pump on the other.

I simply removed a innertube valve stem from a small innertube and attached it to a small hose that slid over the pulse line. That way you can use a hand pump to pump up the pressure.

I then cut out of rubber two carb block off pieces and bolted the carbs back on over each of them, ditto for the b pipe head pipe to manifold.
Does not matter where your pistons are. I pumped it up to 9 and it sat for over an hour with out any drop.

If you need to use my home made kit I can send it to you.
 
in my experience, about 9 out of 10 front seals leak. you can replace it, but itll leak again. ive never had a problem with it. a little oil in that area never killed anyone.

its kinda stupid that there are 2 bigazz seals in the back and a rinkydink peewee seal on the front that takes the abuse of your 'balanced' oem yami flywheel.
 
Madmat this is what im saying. The motor is 9 months old and theres little things starting to pop up like crank seals. Your talking about 9 years out of a motor with out even replacing a wrist pin. Some people critize it but Wamilton said replacing your crank seals once a year is the best you could do to prevent problems. Some last longer and some last as long as yours did. Dont quote me but i believe he also puts alittle grease on the inner ring of the seal for break in purposes. Go ahead and change it while you are there and inspect your motor for other problems.
 

junkyardj

┌∩┐(◣_◢)┌∩┐
dude for the price of a motor is it really worth thinking about? if your front seal looks like that imagin the back ones(which dont have a big cover to protect a air leak) keep in mind almost everyone is buying AM seals which imo should get changed more frequently.. i would bet the guys that say not to change them so often are using oem..
 
Important

I will get everything I need for the leakdown and will be performing it shortly/tomorrow...Thank you for all helpfull advise..I hope it turns out negative

The Engine was never hydro-locked ! Nor water got inside to the point that I had to drag it to land and take the plugs out , nothing to that effect ever happend !!

The seal utilized should have been oem yamahe seals..

The problem is the engine was not built by me and I will have to send the short block back if I want it warranted....which if this (as I was quoted)
" is not of their fault " I will have to pay for dissassemly /repair/reassemble/shipping...which is currently impossible....we are broke

Now tell me who's fault could this be otherwise ?? Yamaha oem seals malfunction ? Me ? Used/New Oem Parts malfunction ?

The good news is that I purchased the engine/shortblock completely assembled....
 
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Orangefinger how did it run before you found the oil in the cover.
Did it backfire at all ?
One good backfire can pop a seal.

If it fails the leak down test.
I would remove the crank and coupler flip the motor split the cases and change the seals,use grease on the i.d. of the seals
Clean the mating surfaces of the cases and run a bead of three bond 1211 around them.Also run a bead where the seals sit in the cases.
To me if its just seal its not worth shiping to someone to get that done I have some seals already so I would just drop them in.
Its easy to fix.
More importantly why did they leak ?
If they were put in backwards them could leak if the cases are damaged where the seals sit they can leak to much presure internally,water,backfire and they can leak.
I have seen plates installed over the seal on the outside of cases to retain the seals on race motors but only on skis with problems that would cause the seals to blow out.
The most common cause of seals poping is backfires and its normally the rear seals that pop but not always.
My 2 cents hope you get it fixed soon it sucks to have yous ski down.
 
All skis are down at the moment and I am getting nervous, the only thing running is the Blaster

Passed on leak down >> Engine has been sent to Builder
 
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