robert0762 Posted April 26, 2010 Report Share Posted April 26, 2010 (edited) I pulled my head off to take a look after the break in and found something unusual to me anyway. Also I had a plug back out on me but I know I didnt have it very tight to begin with. Maybe a quater turn after touching the washer . It was new also.First here is a pic of my domes and they look like oil and water mixed. I wiped some off i am running caster 927 at 32:1 I chechecked tha rad before taking head off and it was full Number 2 The right plug backed out and it looks like some very light pitting on the dome left cyl Here are both cyl Give me some help guys If i run with the plug loose is that enough to cause deto? Edited April 26, 2010 by robert0762 Quote Link to comment Share on other sites More sharing options...
firebanshee Posted April 26, 2010 Report Share Posted April 26, 2010 Give me some help guys If i run with the plug loose is that enough to cause deto? Detonation causes your plugs to come loose. Whats your compression and what fuel are you running? Quote Link to comment Share on other sites More sharing options...
robert0762 Posted April 26, 2010 Author Report Share Posted April 26, 2010 (edited) I was thinking air leaking in . Doesnt make any sense now that I think of it I dont know compression I had kev set up the domes for pump gas they are 23 cc on a 4 mill mx port Edited April 26, 2010 by robert0762 Quote Link to comment Share on other sites More sharing options...
robert0762 Posted April 26, 2010 Author Report Share Posted April 26, 2010 Does ne one have any input on the oil ??? Quote Link to comment Share on other sites More sharing options...
robert0762 Posted April 27, 2010 Author Report Share Posted April 27, 2010 ttt Quote Link to comment Share on other sites More sharing options...
Bill Posted April 27, 2010 Report Share Posted April 27, 2010 I know on brand new plugs you got to crush the washer down on them,hell from seated I can get almost a full turn out of them. Do a google search on piston wash and read up on it, the way your pistons look your pretty darn close to where you need to be. Your running premium pump gas(91 oct or better)right? Do a compression check to see where your at. Quote Link to comment Share on other sites More sharing options...
robert0762 Posted April 27, 2010 Author Report Share Posted April 27, 2010 (edited) I think o rings are bad Edited April 27, 2010 by robert0762 Quote Link to comment Share on other sites More sharing options...
robert0762 Posted April 28, 2010 Author Report Share Posted April 28, 2010 Come on fellas need some feed back Quote Link to comment Share on other sites More sharing options...
toytech Posted April 28, 2010 Report Share Posted April 28, 2010 (edited) I think o rings are bad they dont look good it looks like the one got pinched by the flat of the head and cyl check you head and cylinders with a straitedge to make sure they are flat not warped Edited April 28, 2010 by toytech Quote Link to comment Share on other sites More sharing options...
blowit Posted April 28, 2010 Report Share Posted April 28, 2010 Come on fellas need some feed back K, as I understand it, you have +4 timing, stock cyl, MX port, 91 oct? What is the squish clearance and how are the domes calculated? Ie, usually guys are offering the corrected number so if your dome displaces 26cc and you have say 7cc of piston sticking out of the hole, you have a 19cc dome. Squish and comp are good things to look at, at this point. B Quote Link to comment Share on other sites More sharing options...
robert0762 Posted April 28, 2010 Author Report Share Posted April 28, 2010 (edited) K, as I understand it, you have +4 timing, stock cyl, MX port, 91 oct? What is the squish clearance and how are the domes calculated? Ie, usually guys are offering the corrected number so if your dome displaces 26cc and you have say 7cc of piston sticking out of the hole, you have a 19cc dome. Squish and comp are good things to look at, at this point. B Hjr set up the domes to run pump fuel He said they are a 23 cc flat volume Waiting on new o rings to check squish Guess i gotta go buy a comp tester dont have one Edited April 28, 2010 by robert0762 Quote Link to comment Share on other sites More sharing options...
blowit Posted April 28, 2010 Report Share Posted April 28, 2010 Hjr set up the domes to run pump fuel He said they are a 23 cc flat volume Waiting on new o rings to check squish Guess i gotta go buy a comp tester dont have one I am thinking some numbers are off here. 23cc measured volume - (approx) 6.6cc for piston = 16.4cc trapped. That would be enough to blow some shit in record time. Yeah, I would say testing that comp will be a good start. You do not need Orings to test the squish. Just shell it without the rings. They do not contribute dimensionally. 23cc trapped should be just fine all day long. Why don't you get Kev in on this? I am not sure you even have an issue. It looks like you might have just pinched an oring. Brandon Quote Link to comment Share on other sites More sharing options...
robert0762 Posted April 28, 2010 Author Report Share Posted April 28, 2010 I am thinking some numbers are off here. 23cc measured volume - (approx) 6.6cc for piston = 16.4cc trapped. That would be enough to blow some shit in record time. Yeah, I would say testing that comp will be a good start. You do not need Orings to test the squish. Just shell it without the rings. They do not contribute dimensionally. 23cc trapped should be just fine all day long. Why don't you get Kev in on this? I am not sure you even have an issue. It looks like you might have just pinched an oring. Brandon must be corrected then cause i put 91 octane in it and she ran great till the plug popped out. I cant remember ever taking a head off and having that much oil sitting on it. Is this typical of caster. Is there a poss jetting issue? Is it because some water seeped in? Quote Link to comment Share on other sites More sharing options...
blowit Posted April 28, 2010 Report Share Posted April 28, 2010 must be corrected then cause i put 91 octane in it and she ran great till the plug popped out. I cant remember ever taking a head off and having that much oil sitting on it. Is this typical of caster. Is there a poss jetting issue? Is it because some water seeped in? You are probably all loaded up and you are getting non-atomized fuel up in the head. Yes, caster coats things very well. Expect to see things a little gummier. I am betting you are fine. oring it and run it. A good idea to test comp and squish though. If you give the exhaust port height, that will help determine if your comp is where it should be. B Quote Link to comment Share on other sites More sharing options...
robert0762 Posted April 28, 2010 Author Report Share Posted April 28, 2010 You are probably all loaded up and you are getting non-atomized fuel up in the head. Yes, caster coats things very well. Expect to see things a little gummier. I am betting you are fine. oring it and run it. A good idea to test comp and squish though. If you give the exhaust port height, that will help determine if your comp is where it should be. B I will take a port height measurment and check squish 2 morrow. If you could check back in on me that would be great Quote Link to comment Share on other sites More sharing options...
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