KnightmareCS

iTrader: (7)

I don't think that's normal. I don't know why I'm posting this info this late into the summer. It's been happenening since our first hot day of the year.

What's been done:
New Durlast HD waterpump.
New upper and lower hoses.
New thermostat, not sure if it's 160,180,195.
Later model plastic/aluminum radiator.
Rad cap is in good shape.
88 single electric fan mod.
I do NOT have the air dam. I have the early bird gfx, just not the bottom dam (people rip you off on these so badly!)

What I've seen:
Coolant is nice awesome premixed 50/50 green.
There is coolant flow with the cap off.
There are no visual leaks.
I have not pressure tested it.
I've confirmed my temp gauge with a temp gun.
Timing is good last I checked (had a thread before on here)

Routing:
I had the transmission cooler lines go through the rad, then the aux cooler. When I noticed the car start running hot, I disconnected the cooler lines and now run them only through the aux cooler.

How it runs:
When it's cold in the morning, there's a puff of blue smoke out the rear and the oil psi shows 30-35. I have a breather on the driver side and pcv on the pass. As soon as the temp gauge reads 180, I click on the fan. I have it set up with toggle atm because my head temp switch turns it on too late. Anyways, after driving at highway speed, the car reaches 220* and sits there. The fan is always switched on. Oil psi would be under 30. If I turn off the fan in this situation, the needle would creep up really slowly. If it's reallly really hot out, it would get upto 240-260 and I'd have to stop and cool it off. This is regardless, if I was on the highway or at a light. City driving it is also at 220*.

Basically, I have to leave the fan on or it'd go over 220* and overheat.
No A/C. I don't even chance it and leave the blower hot/cold slider on hot.

Why is it running so hot? What could be the cause of this?
I'm looking into an LS1 fan swap too.

eseibel67

Air dam is a big player in the cooling department. It's the only way the rad can get air when in motion.

KnightmareCS

iTrader: (7)

Right. I'm sure you are right that is what's wrong with it at highway speeds.

Any idea why it's doing it when travelling under 40mph? Street light to street light, etc.

luvmy64

Aiir dam. Gotta have it.

TreeFiddy

Add more fans!

lunaticinaZ

Maybe the thermostate is stuck open. And the coolant keeps flowing and never stops in the radiator to be cooled off. That could cause the hot temp at slow speeds and your MIA air damn would be adding to the problem at highway speeds

KnightmareCS

iTrader: (7)

Can the stat be stuck open if it's opening when cold.
I mean, when you start the car on when cold, there is no flowing. Once it warms up, the stuff starts circulating.

karl's-92'-z28

iTrader: (5)

1. put in a second fan, im gonna add 2 more in the front to push air through.
2. you can check your thermostat by taking it out, put in a pot of water on the stove & turn it on & watch to see it open, when it fully open you can use a thermometer to read the water temp & youll have a rough idea of when your thermo opens.
3. you can make an air dam with that black plastic border things they use in he garden.
4. blue smoke means that you gotta change your valve seals.

hope this helps

TTOP350

iTrader: (8)

Sounds like you have a 195 T-stat. go buy a 160 deg one(dont 4get the gasket) put it in then report back.. an get the airdam on

UnderCover89TBI

iTrader: (25)

if your carbureted you can get by with the 160. have to have the air dam. double check the thermostat. (autozone thermostats suck) buy a stant one or get a mr. gasket, milodon, robert shaw, etc...dual fans will deffinately help, maybe dual fans from a 4th gen that is what I did.

abray1

He will need an air dam. I have the exact problem he does in that mine creeps over 220 and will keep going. I have a brand new 170 A/C t-stat and new radiator cap and my fans are wired direct for now. I have the trans lines run to an external cooler only. I have the be cool 62015 radiator and new aluminum reverse flow pump. I also added two extra fans to the car. A 5.5 pusher over the trans cooler and 12 inch pusher over the condensor. I have another car with the exact same set-up except it is a 500hp 11.5 to 1 heavily modded motor and it runs cool. The vert I just completed is a bone stock 92 Z28 305 auto that I just described has a worn out air dam that is chewed up and bent a little backwards. A friend had a 86 Iroc with an aluminum champion rad and he made an air dam out of aluminum sheet metal and made it a little bigger but angled it forward so it would clear better and his car ran very cool. My other car also has the baffle that attatches to the front spoiler and helps direct air into the rad cavity. I have learned that you must have the air dam and it cannot be bent and chewed up even a little bit or you will slowly overheat. I am going to try and build an air dam out of aluminum like my friend had and angle it forward so it will not hit stuff and get torn up. I have four electric fans and my car still slowly gets hot. I had to swap to a cs144 140 amp alternator to power all the fans and amp. This overheating thing is a pain in the a**.

KnightmareCS

iTrader: (7)

Ok, so I need an air dam, more fans and valve seals.

So I'm guessing:
Air damn will fix highway problem.
More fans will fix stop and go problem.
Valve seals will fix the blue smoke problem.

I'll look into the t-stat too.

Thanks for your help fellas!

abray1

Go to TPIS website and Myron Cottrel (the owner) explains why the 170 is the best all around for performance and engine life. A factory AC stat is as good as any. I bought 4 of them on gmpartsdirect to save on shipping and the part number on the box I am holding right now is; GM# 10220957 ACD# 131-84 GR. 1.246 All you need is the GM part number but sometimes there are new people at the desk so maybe the other number will help them out if you order local. When I put this stat in it helped a lot and crept a lot slower. The aluminum water pumped helped also.

majobis

iTrader: (3)

The air dam is dirt cheap; used. You can find them in pretty much any salvage yard that has a third gen. Although plastic, they were made of strong plastic and they can take good speed bump rash and still stay installed. The only tricky part may be getting it off. Not so much un-installing it, but rather, getting yourself under there if the front wheels aren't on the car in the salvage yard as example. I'd recommend a bottle jack and jack stands to make quick work of it. The junkyard will probably charge 5 bucks and new is only 50 bucks.

After posting this, I noticed you had a Firebird, not a Camaro and apparently, the system is different. Do you need all 3 pieces? If not, Ebay sellers etc. have different pieces for sale. Here is a link for various pieces: http://moderndaymuscle.com/inc/searc...r%20dam&n=4719

karl's-92'-z28

iTrader: (5)

All i did on both on mines was to ground the bigger fan of the two from the relay. It comes on with the ignition & it never went over 200 in traffic on a hot day & all parts are stock.

KnightmareCS

iTrader: (7)

http://cgi.ebay.com/ebaymotors/ws/eB...m=390236895378

The early bird dams are longer than the common ones. I may just resort to the later year ones, but there are no yards close by.

Still on the hunt for LS1 dual fans.

karl's-92'-z28

iTrader: (5)

I heard the ls1 fans dont do much difference than a third gen dual fan set up. As for air dam, on my cousins car all we did was go to a local gardening store & bought some of that black plastic edgeing tbey use in gardens to seperate the grass & flowered areas, worked awsome. Unless you are going for a resto look.

TreeFiddy

I made my air dam from a piece of gal sheeting I had lying around. Painted it black, looked and worked great, made a large difference.

KnightmareCS

iTrader: (7)

Hmm... at this point, I'll take what I can get. I'll be going to home depot, so I'll check out the material.

abray1

I just added the baffle last night and drove the car today and it made a huge difference. My air dam is still chewed up and part of it is bending backwards some but the baffle kept it from going to 220 or the straight up dead center position. Before the baffle it would hang around a needle width above the 220 mark and get there pretty quick and slowly climb. Now it stays at the most two needle widths above 180. The baffle is the curved piece of plastic that bolts to the bottom of the front spoiler and curves back to the bumper support and bolts there horizontally over another piece of plastic to the metal bumper support. I also noticed that the vertical space between the condensor and radiator is open where there is usually a square piece of foam about 1 1/2x 1 1/2 by about a foot long. I am sure a lot of air is escaping through that gap.

mantaguy

iTrader: (5)

If you have a temp.gun,check the manifold temp on both sides,if their really hot like-500 +degrees,check your timing and your cat,converter.cat might be starting to clog up,if so gut it or swap it out.I had all the same things your going threw, car was out of time and the cat was clogged,I gutted the cat and corrected the timing and the manifold temp went down and the engine is running cooler.

abray1

My car is a 92Z vert with 125000 miles and is all stock including the exhaust. I put in a new distributor last year but I forgot about the cat stopping up. That could very well my problem since the exhaust has never been touched. It still has the factory muffler and metal smog lines going to the exhaust manifolds. I have the smog delete pulley I am wanting to install but I am afraid it will screw up the computer. Anyone know what would happen if I took off the smog crap with a stock prom? Anyone know who could burn my prom and delete the vats and usual stuff? They can turn the fans on earlier with a prom change to cant they?

KnightmareCS

iTrader: (7)

Headers + true-duals + straight piped .
Would headers be an issue?

Orr89RocZ

iTrader: (20)

I solved my overheating issues with LS1 dual fans since they have a shroud around them and that helps channel more air across the rad.

engine tune helps control some heating issues, mainly air fuel and timing because you can control EGT's that way and chamber temps in general but sounds like you need more air flow across the rad.

karl's-92'-z28

iTrader: (5)

No straight pipe, get a muffle. Smog delete is no problem with a stock or modified engine, its just for emissions. Hypertech makes good chips.

KnightmareCS

iTrader: (7)

*Straight piped the cats. Have bullet mufflers out back.

karl's-92'-z28

iTrader: (5)

Ok thats better.....lol

KnightmareCS

iTrader: (7)

Bam! Looks like I fixed it. It's working for now. Just sat out in traffic for 10 mins in 83* temps. Normally the car temp would start creeping up beyond 220*. Here's the the result:



And that was my solution. LS1 Duals. The temp shown above is with both fans blasting. I have them on switches with one having a backup from the delayed working thermal head switch. Hope this keeps my temps in check. Next step is to make a shroud, been a bit lazy getting to it.