ParkerTPIz

i just put a rebuilt 305 in my 1991 z28 TPI.....im having abit of a problem....

everything was reconnected correctly as far as the harness and intake go....

PROBEM: i have coolant comming out of my throttle body and out of my headers; obviously there is coolant getting fed into my air intake system some how....

ANY SUGGESTIONS ON WHERE TO START DIAGNOSING????

????: could it be possible that the heads arent torqued on?, because the intake is put on absolutely perfect....i bought the motor from another person so maybe the heads werent torqued on (i know its dumb i should have checked, but obviously its too late for that...)


One of my buddies said it may be the heads, he said that once the water pump caught up and started to pressure-ize the system it would start flowing coolant into the intake if the heads werent torqued on....????

I really need help on this, everything else worked out perfectly, it ran, we got it timed and just all the sudden it started flowing out of the TB and the headers....

THANKS A LOT GUYS...PM OR POST REPLY RSVP

jasonisdn

sounds possiable. check some plugs, to see if you can narrow it down to just a few cylinders or just 1.

ParkerTPIz

now....what does that mean/what should i do if i get it narrowed down to one or a few? :whats the next step?

cars3

I had the same problem with my 89 iroc-z back in 1998, and I brought it to the dealer and they found my throttle body was cracked inside. The throttle body uses the hot antifreeze to prevent it from freezing in the winter when you use cruise control. They changed it and my problem went away. Not sure if your's is the same. You could bypass the throttle body and see if the problem goes away.

jasonisdn

if you were able to narrow it down to 1 cylinder or one side. then you pull that head and have it checked at a local machine shop for cracks and replace the head gasket while you have it off. that would kill 2 possible issues with 1 action. if it is on both sides you would want to check the TB like cars suggested and then the intake itself for any cracks. you need to find out though if it only happening one 1 side or both though first.

ParkerTPIz

CARS3-
I ALREADY DID THE TB COOLANT BYPASS, thanks though

i think what ive decided to do is........tear off the heads and do a head swap...im going to send another set of heads i got in to get completely gone over and rebuilt....

*i figure i might as well do this because if i put all the work into just changing the head gaskets and it still does the same problem.....WHY NOT KILL 2 BIRDS WITH ONE STONE?*

*im for sure going to do a coolant leak test first though...and im also going to try to tighten the head bolts up first.......*

1987IROC350

That was my first thought.

ParkerTPIz

SOOOO.......i found the problem......



we ripped off the heads: we thought it was a head problem.....well we were right: someone dropped a bolt into my intake.....it got sucked into #4, dinged up the piston, and "cast" itself into my head: completely destroying the passenger side water jacket!!!!



easy fix.....but its been driving me crazy: i am a lucky SOB though....: none of the cylinders were scored!!

jasonisdn

well atleast it isn't worse than that.