crank seal keeps coming out...

[FlWAVEBLASTER]

hey guys i gots a question... why would the rear crank seal keep coming out.

i pulled the ski out of the water on the trailer and was running the water out of the pipe and i hear a -=POP=- and the ski has no bottom end. well i look around and dont see anything until i feel down on the driveline and i feel the crank seal spinning around on the shaft.

this is the 2nd time in 2 tanks of fuel that this has happened.... the last time i had a repitule shop replace all the crank seals about a month ago. and now it happens again..

this is on a 701 blaster with a FPP mod ada head with 178psi on a cold motor roughly 185ish on a warm motor....also stock prop


thanks again!!!!

 

[cmeripper26]

Where did the shop get the seals from and were they the OEM seals. Aftermarket seals usually are off just enough to cause this type of problem. Or you may have some crank problems.

 

[Frosty]

are they in properly with the little tabs facing the correct direction? maybe too much grease between the two rear seals causing one to pop out?

 

[sflsurfrider]

got'ny pix?

 

[FlWAVEBLASTER]

got'ny pix?

no pics yet the motor is still in the ski....

but just got back in from looking at it and both seals (iner and outer) are out!!!!!!
the ski runs but has no bottom end at all.
i dont know where the shop got the seals and if they are a/m or oem yamaha's

i am going to call them tomorrow and see what they can do since i only ran 2 tanks though it

i had the crank balanced and welded 1.5 years ago. and the crank seals i had put in were oem yamahas then...

i was doing some stabs, hard turns and tailstands prior to this happening too.

 

[cmeripper26]

Do you hold a lot of water in the engine compartment after subbing and doing stabs. Maybe a leak in the cases somewhere. also find out how the seals were being installed. I only install seals completely dry on the outer edges so the rubber takes a good hold. Maybe they were using a kind of adhesive to hold them in place or a oat of grease?

 

[Cannibal]

Discussion from a few days ago

http://x-h2o.com/showthread.php?t=58139

Consensus is OE seals only and installed dry on the outside, greased on the inside.

 

[WFO Speedracer]

I hate to break this to you but some of the Yami cases are not within the correct tolerance to hold the rear seal in,I have tried glueing them in with Yamabond before as well as several other old school tricks I know but what it comes down to is if you have oem seals in there ,they are installed correctly ,your engine is not backfiring and they are still coming out its time to find a different set of cases.This has been an ongoing problem with Yamahas since the days of the old Yamaha DT-MX series dirtbikes I also saw many problems with the YZ and IT series engines and now with the 1100-1200 and sometimes 650-701-760 series engines.Sorry if this is not what you wanted to hear but alas its the truth.I believe Madscientist just finished up on his third go around on a 701 with this exact same issue.

 

[QuickMick]

no pics yet the motor is still in the ski....

but just got back in from looking at it and both seals (iner and outer) are out!!!!!!
the ski runs but has no bottom end at all.
i dont know where the shop got the seals and if they are a/m or oem yamaha's

i am going to call them tomorrow and see what they can do since i only ran 2 tanks though it

i had the crank balanced and welded 1.5 years ago. and the crank seals i had put in were oem yamahas then...

i was doing some stabs, hard turns and tailstands prior to this happening too.

And quit starting your engine.

 

[WFO Speedracer]

And quit starting your engine.

On most of the couches the fuel pulse line is on the back cylinder so once it runs out of fuel it won't start

 

[FlWAVEBLASTER]

well after reading your post and some others --- i think youre right. time to look for some cases i guess :17:

I hate to break this to you but some of the Yami cases are not within the correct tolerance to hold the rear seal in,I have tried glueing them in with Yamabond before as well as several other old school tricks I know but what it comes down to is if you have oem seals in there ,they are installed correctly ,your engine is not backfiring and they are still coming out its time to find a different set of cases.This has been an ongoing problem with Yamahas since the days of the old Yamaha DT-MX series dirtbikes I also saw many problems with the YZ and IT series engines and now with the 1100-1200 and sometimes 650-701-760 series engines.Sorry if this is not what you wanted to hear but alas its the truth.I believe Madscientist just finished up on his third go around on a 701 with this exact same issue.

 

[QuickMick]

On most of the couches the fuel pulse line is on the back cylinder so once it runs out of fuel it won't start

I guess your mostly wrong because he said it starts but no bottom end.

 

[tom21]

well if it stayed in the last time for a 1.5 years and how many years before that I would say it should be possible to keep it going. yamabond those oem seals in and let it cure.

 

[steve-uk]

this may seem stupid... but have you got it in the right way around?

i had the same issue on a SN SJ, seal was in backwards

 

[cmeripper26]

I would just split the cases and take the seals out and clean them off on the outer rim and clean out all grease and repack them and make sure they go in correctly and are seated right. Also did you find out if they are OEM. U can usually tell after you put the cases back together when you try spin the crank u may feel a little resistance, if thats the case you have faulty seals

 

[smoofers]

I just replaced my crank seals last night as I kept blowing out my rear seals. Upon inspection the outer crank seal had torn a good 2-3" section of the lip off of the seal, therefore, there was nothing left on the seal to "grab" the case halves. Either way, I would replace the seals and not re-use them.

 

[WFO Speedracer]

I guess your mostly wrong because he said it starts but no bottom end.

I said on most couches did I not,seeing that this is on a Superjunk I guess I am mostly right:laugh2:

 

[FlWAVEBLASTER]

welll, went down to the shop, their tech and the owner both claim that they were installed dry and were oem yamaha seals.... thir next guess is that the harmonics of the crank are out of wack ancake: so im pulling the crank this weekend and dropping it off next week. they are going to see if the crank is out of balance--- and seeing that a new crank from sbt is 195 doll hairs and a hotrods one is 505 clams --- a rebalanced crank from a local shop using my crank will my guess be around 250ish?? well i dunno guys maybe a limited b1 will be for sale soon here for yall to bid on who knows--- im getting a canoe, no crank issues there lol

 

[QuickMick]

hey guys i gots a question... why would the rear crank seal keep coming out.

i pulled the ski out of the water on the trailer and was running the water out of the pipe and i hear a -=POP=- and the ski has no bottom end. well i look around and dont see anything until i feel down on the driveline and i feel the crank seal spinning around on the shaft.

this is the 2nd time in 2 tanks of fuel that this has happened.... the last time i had a repitule shop replace all the crank seals about a month ago. and now it happens again..

this is on a 701 blaster with a FPP mod ada head with 178psi on a cold motor roughly 185ish on a warm motor....also stock prop


thanks again!!!!

I said on most couches did I not,seeing that this is on a Superjunk I guess I am mostly right:laugh2:

See your still wrong. He said its on a B1. not a superjunk. :slap:

 

[Mile9c1]

im getting a canoe, no crank issues there lol

I tried kayaking today and it got pretty old, fast. With no motor...