ok heres the problem, i have a GSR block, completely rebuilt with Darton MID sleeves, about 2000 miles on it, done at a reputable shop, and a completly built head by endyn, full tuned and runs fine except..... Overheating!!!!!

ok so after replacing the t-stat, water pump, new coolent with water wetter addative, full sized integra koyo radiator and 850 cfm fan, (its in an eg) its still over heating, now heres the kick. i let it idle to buble out any possible air bubbles, let it idle for over an hour, the coolent itself didnt heat up enough to turn the fan on for 40 minutes. watched the temp on my hondata, never about 206, and thats with the cap off, at first alot off bubbles, then none for three min, then some more bubles, and then it would stop bubbling for 4-5 minutes then i would start seeing bubbles again, finally after an hour and ten min i capped it to go drive it,

made it 3 miles before the temp gague was all the way up... let it idle to see if it would go down, but it wasnt going anywhere. so heres my though,

Air is somehow getting into the coolent flow, causing a vapor lock, which in turn wont let the coolent circulate.. but how would air get in besides a bad headgast, because i just did that and only drove 60 miles on it....

 

Sounds like a bad head gasket that is allowing exhaust gas into the cooling system. I think you should do a leak down test.

 

if the fan doesn't run check the fan relay switch which is a real common problems with honda's, you almost always see someone posting a thread about it.

 

no the fan does, iy just takes along time b4 thr returning coolednt is warm enough for the fan switch