Super Jet Found my problem?

[tor*p*do]

Ski lost one cooling fitting, pipe got a little warm.
ported 61x/61x. C4 pipe.
It then started to not rev up on occasion.
felt like the powerband wasn't there

Pulled head and found this. O-rings look ok, but do you think it looks like my rear piston was power-washed?

 

[BruceSki]

Told you something else was going on.

Once you fix that leaking oring, try and run the ski for a half a tank without the FCV. Then install it and see it doesn't make all that much difference anyway unless you tighten it almost all the way and dry it way the hell out.

 

[tor*p*do]

anyone know what torque to use with the head and girdle bolts on this head?
Uses ADA orings

 

[Fro Diesel]

21ftlb for 8m head. 30-35 for 10m girdle nuts

 

[tor*p*do]

well that's the thing, head bolts are 12mm
and girdle bolts are 14 mm

 

[tomski]

well that's the thing, head bolts are 12mm
and girdle bolts are 14 mm

Head bolts are 8mm thread. Girdle bolts are usually 10mm thread.
Head size of bolt (wrench size) does not matter.

 

[Jhucke]

Love your shark fab head. I looked forever but couldn't find one!

 

[rollin5150]

Coat the orings with some 3bond. Will help seal better

 

[tor*p*do]

Head bolts are 8mm thread. Girdle bolts are usually 10mm thread.
Head size of bolt (wrench size) does not matter.

brain death- too much time in a stinking hot garage!

 

[tor*p*do]

Love your shark fab head. I looked forever but couldn't find one!

It came with the motor package when I bought it. Works great!

 

[tor*p*do]

Coat the orings with some 3bond. Will help seal better

I'll use HondaBond.
Everyone knows it is superior cause it says Honda on the tube!
(j/k, actually it is the same stuff, thanks for the tip)

 

[Fro Diesel]

well that's the thing, head bolts are 12mm
and girdle bolts are 14 mm

And you call yourself an engineer!

I use grease, marine grease specifically on head orings. It keeps them in place and you won't curse when you take it off to inspect cyl walls, etc.

 

[Big Kahuna]

Would not use Blank Bond for orings period.

 

[tor*p*do]

used grease on the dome orings
a dab of hondabond on each end of the big water jacket
sealing oring to keep it in place.
Now my piston wash is back but still having weird occasional failure to rev up? WTH???

 

[Roseand]

Even with my cylinder resurfaced and new o rings and proper torque, my outside waterjacket would still spray a little bit out the front and the back. I have no idea why. A little bit of yamabond was the only way to get it to stop. @Big Kahuna
Wonder if my head was slightly warped from ADA.

 

[Big Kahuna]

13 years of Orings and Grease Only....... If your having to use Yamabond or any sealant, then you have problems with your Deck or Head. Your just masking a problem with bubble gum........

 

[Roseand]

Deck is fine, I'm sure it's my head. It was a light spray that made no difference in pressure in my cooling system but I sealed it just incase...

 

[Pro-pulsion]

I was just reading about this very thing on the Group K site earlier this evening...here is what I found...

" "O" Ring Sealing -

The stock Yamaha cylinders are an aluminum casting with an inserted steel sleeve. After the first 10-20 hours of operation, the sleeve actually drops a few thousandths of an inch down into the aluminum casting. This slight movement is easily accommodated by the stock head gasket, and no leak occurs. However when a racer, preparing a Limited class race boat installs an "O" ring head on to a cylinder with these slightly dropped sleeves, it is very difficult (if not impossible) to maintain a lasting seal on these "much less than perfect" surfaces. Since limited class rules prohibit "any" decking of the cylinder, it is not possible to attend to the unperfect sealing surface on the cylinder."

http://www.groupk.com/superjet.html