jeff_blake

iTrader: (1)

i have a 305 tpi, just did a rebuild on it, new sensors machined heads ect ect. however after idling for about 20-30 mins or so, while we were finishing it up, it over heats. idles fairly high as well, same as befor the rebuild. im positive vaccum lines come into play there. just not sure why it over heats on idle.

camaronewbie

Something not right with your fans. Are they coming on?

jeff_blake

iTrader: (1)

no, nor does the gauge move. always in the middle. I'm thinking it's the fans, and a combo with something else. just always 15-25 mins idling starts gettin hot, to hot.

camaronewbie

Well the fans should definitely come on by 20 minutes of idling. That's your problem then - these cars have to have a fan running to keep them cool at idle, or they will overheat. Sounds like your guage is shot as well.

Start diagnosing why the fans don't run. Here's a troubleshoot guide:
http://www.austinthirdgen.org/index.php?pid=36

Get the fans working properly, then worry about the guage. The sender for the guage should be driver side head, between #1 and #3 spark plug - may need replaced, or maybe the wire is broken. Since the guage always sets dead center - might be a power wire issue to your gauge cluster as well (the sender in the head is a resistor for the ground side wire to the guage).

jeff_blake

iTrader: (1)

alright awesome man. it's not a rush, so Monday when I head out to do more on it I'll do more trouble shooting. just tryin to get another iroc on the road. there hard to come by down here.

sofakingdom

iTrader: (1)

If the gauge shows the same temp, what makes you think it's "overheating"?

Have you tried fixing the gauge? Does it indicate all the way cold when the motor is cold?

jeff_blake

iTrader: (1)

no sofa, gauge doesnt move at all, hot cold. warm you name it. gonna go mess around more with it later. ill keep yall posted.

jeff_blake

iTrader: (1)

well, an update for ya. got it running, and attempted to make it from the garage, to my house. roughly hour and fifteen minute drive. drove great for about 45 mins or so, then once we hit traffic and red lights it got up there in temp. (yes, the gauge doesn't work) needless to say at a red light it started to overheat, pulled over and let him cool off. put more fluids in, waited until he cooled off. headed back out, drove for another 10 minutes or so, same thing happend. then got tried for attempt 3, ran excellent like i did for the first 45 mins. i did notice the upper rad hose was very very hard, which leads me to think somethings clogged, or the thermostat is faulty. the fan doesnt kick on either still, but that wouldnt make the hose hard..still idles high, which i think has to do with a vaccum leak, and a combo of the throttle body spring not bringing it back all the way. least its home, after alot of cash and time into it.

camaronewbie

Well, these cars have no air flow to the radiator without either moving or the fans running. No fans means overheating is guaranteed in traffic, being stopped, etc.