david068513

iTrader: (2)

Ok 92 z28 350. I just replaced injectors, iac, distributor. It had been sitting awhile. Reset timing also.


Before it sat on a extremely hot day it would get up in the 230-240 range while in heavy traffic and you'd have to rev it and turn the heat on to get it down. Now I drove it after I did the above upgrades and it wasn't over heating under normal traffic conditions it did how jump way up after doing a small burnout in front of my house. By the time I backed into the driveway right after doing it, 240 temps were on the gauge. It went from 215 ish to 240 in a matter of seconds. I was getting hard on it too alittle this same day and it never did this. Only did it after the burn out I'm guessing cause it wasn't moving and flowing air into the grill. Also both dual fans are wired on all the time. I've flushed the radiator before I wired the fans up to be constant and that didn't help. Could it be a timing issue? It's set to stock. Could it be a blockage ? I flushed the radiator and it didn't help? What else can this be? Air dam is there.

david068513

iTrader: (2)

david068513

iTrader: (2)

TylerSteez

iTrader: (3)

What condition is your water pump in? are you running a thermostat?

david068513

iTrader: (2)

Yes I'm running one, Stock t stat temp, rad hose hot to the touch and pretty hard. Can squeeze still but not a ton. Stock water pump.

mk1431

Do you have the air dam thats under the car still. They tend to run hot if its missing do to very little grill openings

david068513

iTrader: (2)

Yes, it's there.

James Sutton

iTrader: (2)

What thermostat is installed? 190 degree thermostat helps engine run cooler. If sealant is used on thermostat, it can cause thermostat to jam. If it jams, you're in for a world of hurt. But you know all this....

david068513

iTrader: (2)

Stock t stat, was changed when this issue first started a long time ago.. 3 years?. It's not a daily driver. I don't drive it much. Trying to finally get everything worked out.

86Z

iTrader: (4)

i'm gonna say it's not over heating and it's probably the gauge, verify the coolant temp besides the factory gauge that's probably off 20 or so degrees.

david068513

iTrader: (2)

Now can it be only the gauge of it only does it after sitting, getting on it hard, etc. that wouldn't be a gauge if it reads correct all the other time and it never varies expect under these conditions

86Z

iTrader: (4)

it won't keep a constant temp, if you drive it hard and sit in traffic the temp will fluctuate. i bet you the gauge is off. my stock one would hit almost 260. my chevy truck is a good 15 degrees off of what the gauge says...

david068513

iTrader: (2)

So even though it keeps a constant temp all the other times and it will go down if I rev it like it's overheating or drive it and get air flowing you still think it could be the gauge?

-=Z28=-

iTrader: (3)

Sure its not your timing? Fans coming on? Does it overheat when you have the heat on high? I would check your timing tho.. Another thing is you can buy a cheap lazer hand held temp gun for 30 bucks now. Use it to compare to what your gauge says. you can shoot it anywhere you want to see temps too. pretty cool tool.

86Z

iTrader: (4)

look dude i just suggested one thing. if you are going to tell me it's not the gauge then don't ask for help. you may have something else going on but you're gauge is not accurate. none of them are from the factory.

david068513

iTrader: (2)

Timing is set to stock? I would highly doubt it's timing. It's been set twice now to double check.. Hmmm.. Idk..
I was asking why you thought that after the facts. It doesn't vary at all while moving or driven long times or distances only after these conditions that is why I would not think its the gauge. I'm asking why you think it would only do that while sitting etc.

david068513

iTrader: (2)

And no having the heat on actually makes it run cooler alittle on the gauge. Barely noticeable and yes fans are constantly wired on full blast

-=Z28=-

iTrader: (3)

Huh. Id get one of those guns and compare to gauge. that way you KNOW its correct or if its cooler or warmer....

david068513

iTrader: (2)

Where's a place to get one the cheapest?

JJ88GTA

Have you pulled the drains on the block to see how clean things are in there? Is there any visual signs of build up in the rad/hoses/t-stat housing from additive or stop leak etc? It also might not hurt to test/ try another new thermostat. Cheap.

david068513

iTrader: (2)

I was gonna change the t stat just in case again. I haven't pulled the drains in awhile but I don't remember any huge build ups

ploegi

How does the radiator look? Any debris in the fins?

david068513

iTrader: (2)

Not perfect, it's ok. It's been in there the whole time I've owned the car 8 ish years. I've changed the water pump, t stat, pretty much everything but the radiator.

-=Z28=-

iTrader: (3)

Ive seen em all over for 30 -40 bucks. you can spend over 500 on a really nice one but I dont think thats necessary

david068513

iTrader: (2)

I'm gonna check it thurs,along with the timing to double check and go over the cooling system and see what I find.

Bob88GTA

iTrader: (2)

When you wired your fans, are the fans "pushing" or "pulling"? They need to be pulling air through the radiator.

And yes, your temp gauge is off.
Also, you ain't "overheating till you start to boil over and puke ANTIFREEZE/COOLANT all over the place. These cars ALL run hot.

-=Z28=-

iTrader: (3)

I agree with ya Bob. gotta have those whirly birds spinning the right way. And, Why do they run hot? Its like you could take the same motor and put it in a truck and it would run cool, put i in a 3rd gen and it will run hot. Strangest damn thing i ever hear of..... lol

Bob88GTA

iTrader: (2)

What I will suggest, just from doing this myself, and getting great results on my 5.7 TPI is to take the radiator out, take it to a radiator shop and have them take the tanks off the ends and "rod" it out. They run different size rods through the passages to clean all that crud out, then they boil it and put the tanks back on. It cost me around 70 bucks.

Then run 50/50, 40/60 coolant and distilled water. NEVER had a problem since and that's been 15 years ago!

But that's just what I did; unmodded, unmolested, stock, and well maintained car

-=Z28=-

iTrader: (3)

I did the same thing. Well similar. A friend owns a radiator shop and they built my stock into a 4 cor hog. And put in a bad **** tran cooler. I swear that I can put 5 gal in that damn thing and it wants more!!

1983Chimaera

Run down the cooling system basics;

Check condition of the radiator:
- fins clear of debris, not bent/mangled
- no visible leaks from seals or hoses
- radiator cap gasket in good shape
- not blocked (leaves/debris)
- with engine at temp check for cold spots on the radiator (usually at the bottom, evidence of blocked passages)
Check condition of the air dam:
- not missing/broken
Check condition of the fan(s):
- if electric, check for proper operation
- if mechanical, fan clutch not worn out
Check Hoses:
- Not kinked/collapsed/leaking/steam leak. Look for evidence of pinhole steam leaks in the form of yellowish green deposits or "snot" at gasket areas and around hose ends.
Check water pump:
- no sign of leakage from weep hole
- no odd noises
Check coolant:
- proper color/mixture
- proper fluid level (has the system been "burped" to remove all air?)
- does system pressurize (engine at temp, thermostat open, radiator cap on and upper and lower hoses not soft)?
Check heater:
- does hot air blow from the vents with engine at temp (heater core not clogged?)

Other things that can effect engine temp are detonation, trans issues (auto trans generate a LOT of heat), mineral deposits in the engine/heater core/radiator that block coolant flow (from running tap water), head gasket issues, and improper timing.