Protec Head O-ring Conundrum

[Dustin Mustangs]

My blaster has been under the knife for the past couple of weeks. Well, I took it out today to test all of my labors. Mod pipe, protec head, yadda, yadda, yadda... It didn't seem right from the get go which eventually lead me to a compression test that indicated one cylinder was down. Back on the trailer she goes. :grumble:

I get home and pull the head being I was pretty convinced something wasn't right with the o-rings when I installed them. What I found when I pulled the head is attachment 1 and 2. Attachment 3 and 4 are what the o-rings looked like on the way in.

Are these the wrong size or what? Obviously the second one is completely blown but they both looked alot worse then I would of expected something that you can supposedly reuse even aside from the blown area. I am not familiar with o-ring sealed heads so I really don't know what this should look like before it goes together or when you take them apart.

They were viton and the exact size protec told me to get (-153) for this head when I called them. Any ideas here? I really don't want to stick the stock head back on. :dead1:

 

[Matt_E]

Did you maybe pinch the old ring when you put the head down? (Did you put some vaseline on it to get it to stick?)

Massage the new one in there. They are almost always a little too big, but you can massage it in.

 

[keefer]

Yep you gotta use some vaseline or light grease to make them stick inside the grooves while you fit the head to the cyl. Otherwise they can pinch and you will get the results you have.

 

[BigDog452]

you can use grease too but what he said

 

[Dustin Mustangs]

So the pictures of it sitting on the head look right to you Matt? One deff seemed too big to me, like in the pick, but I really had nothing to base this on and intalled them anyway. The other one however fell into the groove w/o much of a fight. I imagine the blowout is right where that one was hanging out of the groove. Oh, and I did used grease in the groove to help them stay in place.

What has me really scratching my head is how horrible they look even away from the blowout, the other cylinder especially. It almost looks like I used permatex on them but I didn't. Their cross section is deff not round anymore, like they melted or something. I attached another pic of them off the head that shows this a little better. They are supposed to be viton so I highly doubt things got hot enough to melt them but who knows. If that was the case I'd likely have other damage wouldn't you think? I didn't see any and it looked like I was running overly rich.

 

[Motorheads5]

I have a dumb question also but it might pertain to the same problem isn't there suppose to also be a head gasket? because I just removed my westcoast head on a kawi 750 and you have the head then the o-ring's then a gasket and then cyl. surface?

 

[robertg]

You either have O-rings or a gasket, not both. Someone may have put a head gasket in there to lower the compression.

 

[Motorheads5]

sorry not trying to threadjack here but I did some searching and found the answer to my question http://www.x-h2o.com/threads/13960

 

[Kennay]

So the pictures of it sitting on the head look right to you Matt? One deff seemed too big to me, like in the pick, but I really had nothing to base this on and intalled them anyway. The other one however fell into the groove w/o much of a fight. I imagine the blowout is right where that one was hanging out of the groove. Oh, and I did used grease in the groove to help them stay in place.

What has me really scratching my head is how horrible they look even away from the blowout, the other cylinder especially. It almost looks like I used permatex on them but I didn't. Their cross section is deff not round anymore, like they melted or something. I attached another pic of them off the head that shows this a little better. They are supposed to be viton so I highly doubt things got hot enough to melt them but who knows. If that was the case I'd likely have other damage wouldn't you think? I didn't see any and it looked like I was running overly rich.

They are all melted because they were exposed to all that heat from combustion, because it wasn't sealed off.

Light grease, new o-rings, and you are good to go.

 

[kevbo]

An O-ring will not seal combustion pressure, its there to keep water away from the steel liner. Your head and cylinder needs to be lapped perfectly flat.

 

[Dustin Mustangs]

After looking closer at them this morning I noticed they aren't melted. They are pinched on the inside and outside because, I think, they were too thick to fit the groove in the head. The last picture in my first post really shows this. I guess an easy way to find out is to put a new set in, torque them down, and then pull them back off and see what they look like. Either way protec is going to get a call today to see what they have to say on the matter and to verify what size I should be running. Thanks for the input on this.

 

[tshank123]

Does viton come in black? The viton I've seen is more of a brownish redish color.

 

[Matt_E]

Yes, it comes in black.

 

[Mouthfulloflake]

-153 is 3/32 wide

043 is 1/16 wide

maybe its an 043 ring groove?

 

[dbrutherford]

You either have O-rings or a gasket, not both. Someone may have put a head gasket in there to lower the compression.

Actually on a West Coast Kawie head they did have both. I believe teh gasket was to meter water correctly inside the head/cylinder.

Best bet is to contact www.PacificJetSports.com Gordon has some last I read somewhere.

 

[nikad58]

Pro-tec uses two o-rings on most their heads.. a big and small.. thats the small one.. call them again and ask Carl..

 

[demolition_x]

Does viton come in black? The viton I've seen is more of a brownish redish color.

those are the silicone o rings.

are you sure the oring diameter is the right one? it looks a little thick, i would imagine it would be 1/16th inch diameter. i cold be wrong but the ones you have look quite thick.

 

[Dustin Mustangs]

I'm pretty sure the orings are not the right size. I called protec and they verfied that these should run the -153 oring. He even rifled off the actual dimensions of them which check out with what a -153 should be and what the ones I got from mcmaster mic at. The guy at protec also said that the orings should be about the same thickness as the groove is wide and thicker than it is deep. This is not the case. I'd say they are easily 50% too thick to fit the groove and I'm pretty sure that's why they got chewed up so bad when I torqued them down. I thought maybe I got a 650 head (bought it used), but the protec dude said those run the same oring. As mouth said above, the -043 is pretty much the same diameter and a nominal 1/32 thinner so I have some of those on the way. If they don't fit I am officially out of ideas.

 

[cattledog]

good luck with o rings , how come things arent more simple who needs o ring hassles, i have heard that a lot of people use high temp silicone around o rings are you going to install them dry?

 

[Dustin Mustangs]

That was the plan, I didn't realize there were other options. I guess I'll worry about how good they seal once I find myself a set that fits.