Jaystre Posted October 6, 2013 Report Share Posted October 6, 2013 broke a small piece of the inner lip that holds the o-ring in place ,just above the exhaust port about 1/2 wide . what couldve cause this? Quote Link to comment Share on other sites More sharing options...
trickedcarbine Posted October 6, 2013 Report Share Posted October 6, 2013 Few things could cause it. Do you have a pic of it? Other wise I could only speculate that it was due to clearances/tolerances being over looked. Maybe assembly error? Detonation? Have to see it to have a real idea though. Quote Link to comment Share on other sites More sharing options...
DUSTY05 Posted October 7, 2013 Report Share Posted October 7, 2013 Mine did the exact same thing.. both domes but mine were small chips Quote Link to comment Share on other sites More sharing options...
n2otoofast4u Posted October 7, 2013 Report Share Posted October 7, 2013 What bore? Sometimes when you get a larger bore the material between the combustion chamber and the oring gets thin. Quote Link to comment Share on other sites More sharing options...
DUSTY05 Posted October 7, 2013 Report Share Posted October 7, 2013 Mine was stock cyls, stock bore, Noss head and 19cc domes.. Kevin at HJR said it was from "compression".... Idk Quote Link to comment Share on other sites More sharing options...
Brap_Life Posted October 7, 2013 Report Share Posted October 7, 2013 Piston pocked on exhaust side at all? Quote Link to comment Share on other sites More sharing options...
J-Madd Posted October 7, 2013 Report Share Posted October 7, 2013 Is it a dome with an oring groove, or just the ledge to hold the oring on? If it was a groove, did you put a lot of grease on the oring? The grease won't compress and will blow oring grooves when the head is torqued down. Quote Link to comment Share on other sites More sharing options...
DUSTY05 Posted October 8, 2013 Report Share Posted October 8, 2013 Mine has a ledge... i had 19cc domes and ran 93 pump gas in it,would detonation cause this?? My plugs and pistons are in great shape... Quote Link to comment Share on other sites More sharing options...
J-Madd Posted October 8, 2013 Report Share Posted October 8, 2013 Deto can cause that, but it's gonna show on the piston and plugs first usually. Quote Link to comment Share on other sites More sharing options...
DUSTY05 Posted October 8, 2013 Report Share Posted October 8, 2013 Deto can cause that, but it's gonna show on the piston and plugs first usually. Exactly What i Thought Also.. fuk if i Know What Happen Quote Link to comment Share on other sites More sharing options...
Jaystre Posted October 8, 2013 Author Report Share Posted October 8, 2013 (edited) it is a dome with a o-ring groove ...didnt put that much grease i would think . piston and cylinder are fine but the o-ring on the other dome was starting to break up at the same spot above the exhaust port...ill try to get pics . bore is 64.5 Edited October 8, 2013 by Jaystre Quote Link to comment Share on other sites More sharing options...
trickedcarbine Posted October 8, 2013 Report Share Posted October 8, 2013 Just pro design shelf domes. Quote Link to comment Share on other sites More sharing options...
camatv Posted October 9, 2013 Report Share Posted October 9, 2013 if the "break" is obviously a material failure ( just snapped off) then can be a lot of things... if its sand blasted off or blown off melted off etc its DETO> i have seen SOME heads blow out where the o-ring seals from to much internal pressure or bad dome design, and/ or weak ass head studs. the banshee stock head pattern has a very weak inherent problem in that area. the dome just does not have the same sealing pressure that the rest of the head has. Quote Link to comment Share on other sites More sharing options...
Jaystre Posted October 10, 2013 Author Report Share Posted October 10, 2013 its not melted off ...the domes seem fine except that broken part . these were domes cut for a 4 mill Quote Link to comment Share on other sites More sharing options...
J-Madd Posted October 11, 2013 Report Share Posted October 11, 2013 Still no pics? Was it torqued properly? Oring might have blown and let water on a hot dome??? But that usually causes deto and other damage so I guess we're back at square one. Had this motor been run for a while or was it a new build? Maybe the deck wasn't square? Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.