ada orings,anything better out there

[masterblaster]

I was using the black orings that mcmaster sells for it,but even sealing them down with yamabond they still got hot spots and blew out twice in a few months. I got the brown viton high temp ones from mcmaster and one of those blew out as well?

 

[tricky1]

you may want to check or have the top of your cylinder decked.

 

[demolition_x]

there is probably another issue, i have been using the same dome orings for 2 seasons.

 

[Matt_E]

I have never had an O-Ring from ADA or McMaster blow in four years of use.
The O-rings don't hold compression by themselves. If you're blowing them, your motor has other issues. The O-rings blowing are just a symptom.
I'd check if the head and cylinder are warped.

 

[stanton]

just replaced an ada head that was worn out doin the same thing.
id say time for a new head.

 

[Crab]

Stan, tell us what exactly was worn out, all I can think of is corrosion.

 

[stanton]

where the domes touch the head, it broke through the anodizing and from there it got worse and worse. the domes had notches in them too.

 

[SUPERTUNE]

Anytime when working on an engine with a ADA head you need to measure them before re-assembly.
Measure the depth from the step to the deck, this measurement is .499, now measure the dome thickness, should be .502.
This is how the ADA head works with .003 interference (crush) on the freestanding sleeves that Yamaha oem cylinders have.
As the head shell gets worn and the domes get worn down this is when you need to replace them.
Always make sure to check the cylinder deck for warping and for any sleeve dropping below the deck.

 

[masterblaster]

the black rings from mcmaster looked half melted when i removed the head,they must not be right for it,the brown high temp viton rings seems like they may work better,this head is not worn out,its only 2 yrs old.
wonder if the oem ada orings are any better

 

[augustaf]

If you are unable to measure you can usually get a visual clue looking at the wear marks, domes to head shell. Dancing domes are not a new phenomenom. 20 years ago West Coast aftermarket heads for 650 Kawis had domes so loose they would vibrate out the spark plugs!

 

[orangefinger]

I had some dome from ADA in which the gap that holds the actual O ring was to large barley noticable ( rare manufacturing defect ) make sure the gaps are identical on both domes...

 

[#ZERO]

What size bore are you running.

 

[freeride4me]

I had the same problem. You could see the impressions of the head on the dome tops. Well I guess you could change the domes($80) & probably should have the head cut($50) or if you have the cash buy a new setup($300+).

Or if your broke & its the weekend & you want to ride, go down to Harbor Freight(or equivalent Chinese tool shop) & get an assorted pack of wet/dry sandpaper. Then find a thick flat piece of glass(the wife won't be happy when she finds you using the dining room table---Oh well!) & start doing figure 8's with the head. Just keep popping in & checking the domes until they protrude a little bit(Chucky says .003").:fing02:

Bolt it back together & go riding. :splatt:

 

[masterblaster]

dont think its warped and domes look fine,just crappy orings,we shall see how long the brown ones last,whats the beast sealant to use on them?

 

[Matt_E]

No sealant.
I do use some vaseline to hold the O-Rings in place.

 

[Flash-FX]

A couple of years ago, I was running this engine "setup" that was assembled by a so called "engine builder" . I was told this package was set up for pump gas, but I ran 100LL in it anyway, it ran ok (not to get into too many details) for a whole season like this...Now off to Daytona for a week at the freeride. I started to run premium fuel there and after 2 days I started blowing o-rings. By the last day, the o-rings lasted only about 15 min.
I guess mild detonation (from the crappy fuel) started to rattle the head shells and tear up the o-rings. (what it WAS...85mm flat tops,26cc domes,compression measured 160psi, -5deg static/advent Y701-6, squish was .062").

 

[masterblaster]

that sounds like it would have been fine at 93 oct,no advance and little comp with a large squish?

 

[Big Kahuna]

dont think its warped and domes look fine,just crappy orings,we shall see how long the brown ones last,whats the beast sealant to use on them?

MB, when one of the best guys in the business takes his time to respond to you, why dont you listen to him. Forget all of us armchair mechanics. Listen to the guy that knows. You have a problem with your Head, Domes or Cylinder. Not the orings.

 

[masterblaster]

Trust me I know chuck is the man,He is working on some other ada domes for me on a diff motor,Ive made all the measurements on this head and cyl,its not warped,its only 2 yrs old and has never been overheated badly.The black o rings mcmaster sells actually melt a little from what I can tell looking at them. Chuck told me what to use to seal the o rings down,think it was 1211 sealer,this is sim to reg yamabond isnt it

 

[D-Roc]

i had an o-ring blowing problem, my sleeve dropped, i deck my cylinder, tightened up the squish a bit and it has been fine ever since. oh yeah it was chuck's comment that clued me into why my oring was melting/ blowing out. i use Hylomar/Ultimate blue race formula as a sealant for the ada head, it also holds the o-ring in place for install so they don't move and you pinch them. Acetone removes the ultimate blue without scraping or breaking a sweat and in never sets up so the orings never get glued in and break upon removal of the head. Just my 2 cents.