Superjet blowing out ADA o rings

whennotsailing

whennotsailing

Location
grand rapids/holland/Grand Haven MI
Any thoughts on the following narrative....

I let my 701 ski sit for a couple years (heated inside, properly winterized), I got it out the other day, fired up and ran for about 10 minutes before issues. I noticed it wasn't pissing water thru engine, so pulled up on the beach to investigate. nothing visibly wrong.... Cranked on it, got it running, and engine seemed to fill itself with water and die. Took her home and found the ADA head gaskets / o rings from domes to cylinder head were partially gone on the front side of the rear cylinder. No problem, chalked it up to o rings sitting and getting old..... installed new rings installed, got it running again and it did the same exact thing, front side of rear cylinder o ring is gone. Ski ran good for 5 - 6 minutes, stopped pissing water, bogged down, and done.

It has all the tricks, msd, b pipe, dual 44's, etc

Another question I have... The McMaster carr parts thread,,, some appear to be running oil resistant buna-N o ring cord stock for the outer head seal, part # 9407K21... What do you do with the little gap created by having a non continuous piece? Isn't that a source for water / air to escape and cause issues?
 
Blue

Blue

Judging your cheapness
Location
St Cloud Florida
Sometimes the sleeves in the cast cyl settle lower over time causing a larger gap than normal between the cyl and the dome which will cause the orings to blow out. I have also seen the domes and head shells wear over time causing the same issue but if your head is new most likely the sleeves have dropped. This can be resurfaced to correct the issue once the cylinder is removed. Maybe consider freshening up ur topend while its apart. As for the outside oring most are cut to size and glued with super glue. They never seem to leak and seem to last for years.

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Carbon Jet

Carbon Jet

Location
SW FL
I personally use the new/replacement O-ring kit from ADA. I don't care how well people say the cut-to-length ones stay together with crazy glue. not worth the risk to me... especially if you ride in salt water. any potential to have water ingestion is just not worth my time and money over a small little piece of rubber. I also check/retorque after the first heat cycle.
 
whennotsailing

whennotsailing

Location
grand rapids/holland/Grand Haven MI
Its a real ADA head..... Can't see any evidence of sleeve settling/lowering in cylinders, they feel and look flush. A few pics attached, maybe that will give you some insights? It blew out same o-ring in same place both times, the front or middle section of the rear cylinder, see the black around that area? Note the camera flash makes things look waaay worse then they are. This ski has maybe 5 - 6 full tanks of fuel through it since a complete overhaul.

Any other thoughts?

Thanks for superglue trick on the exterior o ring - seems shady to me too now that I think about it. As I recall, the first one I had in there was a length of it that I didn't even superglue and it did seem to hold up for a couple of years (amazingly enough). Surprising McMaster doesn't offer something the right size that's continuous?
 

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Harbor

Harbor

Location
Stockton
When my billet cylinder was doing this, I used a straight edge and .001 & .0015 .002 gauges to measure for flatness of the deck and any sleeve drop. Mine was .002 in one spot. I then used a knife honing stone on the fine side with some w-d 40 or honing oil and paper towels in the cylinders... Then did figure 8 pattern’s with light pressure across the deck to square it up till an over haul could be done.. the stone cleans the high spots and makes lower spots more visible..... so it was a helpful tell...

Pulling the cylinder and having it decked as mentioned earlier is obviously very desirable....,

Another thing is make sure all your threads are able to hold the 18 pounds of torque...

Another tell I did before stoning the deck was, I removed the dome from the head, left spark in and used the dome to run over the steels cylinders deck surface and I could feel it was bowl shaped... the aluminum around the steel sleeve was slightly higher the the steel sleeve

If you stone the deck, then swap domes front to back and see if issues follows the dome...

The hardware store sells stones, they are like 6 inches long, 2 grits and about 1 3/4 thick maybe... just be carful to not let the very tip of your finger get low on the stone as you move around the cylinder.. it takes off your skin lol...
 
Blue

Blue

Judging your cheapness
Location
St Cloud Florida
It doesnt take much drop in a sleeve or warped mounting surface and the orings wont hold. I see this with alot of cylinders i get, almost all have some un eveness and require milling to tru the top deck.

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waterfreak

waterfreak

I had a vision!
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Location
s florida
JetManiac said:
Dome to head shell can wear also, causing the dome not to seal on one side. If sleeve is not dropped and cylinder top is also true, then that is probably the issue.
Click to expand...
I second that! i had one on one of my old ski do that. Blew the o ring after 10 minutes of riding
 
Blue

Blue

Judging your cheapness
Location
St Cloud Florida
Typically they both wear a little. If you were changing plugs and the dome spins it could damage the oring causing ur issue. I still bet the cylinder deck is not tru.

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JetManiac

JetManiac

Stoked
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orlando
whennotsailing said:
I don't fully understand what you mean here.... Are you saying head is worn, or dome is worn?
Click to expand...

It is more likely a problem with your cylinder, but if not, I was giving you another thing to check. Pull domes out of the head shell and inspect the dome to head shell areas where they touch around the edges. Look for wear in those areas.
 
JetManiac

JetManiac

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Quinc said:
5200 your domes in place so they no longer spin. Not sure why ada doesn't have it where the domes lock into place...
Click to expand...

This is not a common issue or one that happens often, very rare. If head is installed properly on a good cylinder, then it is never an issue. It is only when a head isn't torqued correctly, or head comes loose, or sleeve drops/out of true that it can happen over time.

Domes do not 'lock' in other common brands either. Dasa, Thrust, etc. I would view it as a solution in search of a problem.
 
orangefinger

orangefinger

Location
Reno,NV
Use ADA guidance for torque specs and method , torque specs we used instead of 18 for head final 20-22, instead of 23 girdle for final we used 30-35 for girdle ....

These specs had been given to us by chuck long time ago and never had any problems with it.....

Again opinions as always will differ......
 
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