What should the temp run for a 1990? The fan starts and the temp is high when not moving.

 

L98's are notorious for running hot. You must clean in front of your radiator, alot of road debris gets sucked in there. Then you can put in a 160 thermostat in and put in a fan switch to start the fans earlier, a computer chip will also do the fans earlier but is way too expensive. My normal coolant and oil temps were in the 220-235 range in town. On the highway it can get it down to 205 oil and 190 coolant.

 

Your cooling system was designed to operate at 185 or 195 (I don't know which for a 90, my 87 is 195). The fan is programmed to come on at 228 F and the aux fan at 238 F. In summer and below 30 mph, you temp will exceed the thermostat rating and this is normal and not dangerous. The main fan can be forced on at a lower temp to reduce temperature rise when slow or stopped by a new prom chip or manual switch or aftermarket temp sensor/fan switch. Some members here think that a 160 thermostat will keep their coolant temperature from soaring, but it cannot do that because once the coolant temp gets to a few degrees above 160 F, the thermostat is wide open and can no longer control the coolant temperature. In the winter time , because of the low air temps, your cooling system can maintain 160 with a 160 thermostat, but that is not a good idea because water condensation in your engine oil is not removed very fast at this temp and it will become acidic and start reacting with your metal engine parts. Engine wear is higher with this coolant temperature, and thermal efficiency is lower which predicts lower engine HP.
Vander 86's post is proof that a 160 stat doesn't keep the engine cooler as he states that his coolant temp is 190 on the road. You can keep your engine temp from high excursions when stopped by keeping the debris out of the front of the radiator and it also gets in between the a/c condenser and the radiator. This debris reduces air flow and thus the ability to remove heat from your engine coolant. With some work, you can remove the top cover on the condenser and radiator to clean between them. I tried a lazier way this past summer and it worked. I blasted water from my garden hose backwards through the radiator (from main fan forward) and then blasted water between the gap around the radiator filler which flushed some debris out the bottom .
If 160 stats worked, don't you think that GM would at least offer them for C4's? They don't, and furthermore, they recommend that you install the thermostat originally called out for your year C4. Its your car and you can do what you want.

 

You made some very good points... Thats why I keep mine stock...

 

For those in the DFW area, I took my Ruby to David
at the Corvette Shop where he installed a fan switch
which turns on both fans at 200 and off again at 185.
I asked him specifically about the 160 stat and he
recommended AGAINST it saying among other things
that running too cool also changes the air/fuel mixture.
Running too rich can foul plugs, lower gas mileage, etc.
He recommended the 190 stat, stock chip and this thermal
switch.

After the installation, he started it and let it idle to 200
and sure enough the fans brought the temp back to 190
and held it there with no forward momentum whatsoever.
Just sitting in the garage.


Just my $.02.

:seeya

 

I dont have a 160 thermo, i was just suggesting ideas for him. It gets cold in SC over the winter and i dont feel like changin it to 160.

 

I run a 160 stat and want the radiator to start flowing as soon as possible, in Phoenix 110+ degrees is a usual temp in summer and winters are pretty mild,no 160 stat won't help it run cooler but here we want anything that helps.

:jester :jester :jester

 

MY favorite stat is the compromise 180f, and fans on at say 195 and off at 185 or so....oil temp is hi enough....and engine stress is reduced, no way aluminum and steel can take that super high 240f crap and hang together for long, bad enough as it is....

GENE

 

Hey 2HIP4U, do you have a number for David at the Corvette Shop? I have the fan switch already, but I can't get the plug out to install it. He might be able to loosen the plug so I can finish the job.

 

The only thing I would add is flush the the radiator and I use water wetter. I use 2 bottles and it droped my temp by 20*.

 

:yesnod: :yesnod: :yesnod: :yesnod: Water Wetter is some great stuff. I dropped my temps by about 10 degrees by adding it.

 

94Controller:

The Corvette Shop is located at 11235 N. Stemmons
and the number is: (972) 243-3033. David is the
owner and top wrench and has 20 years experience as a
Corvette tech.

To install mine, he pulled the inner wheel well liner
at the driver's side frame rail, then turned the wheels
to the left. He used a breaker bar to free the sender
then ran the wires through that black plastic conduit
like the factory uses. He then tied it into the lower
relay on the radiator shroud. The job is so clean,
you wouldn't know it wasn't factory.

:seeya

 

Unless I know precisely what condition the hoses are in, any temp above 212 gives me the creeps. Add to that different expansion rates for aluminum and iron, accelerated thermal oxidation, lubricant breakdown, compression-induced detonation, etc. I don't care what the manufacturer says, keep it cool, boys.

My question is can anybody recommend a good temperature-adjustable switch/relay setup that will plug into the Corvette wiring harness?

I've already experimented with the crappy open-contact, huge-blinding-flash type temp switches that most hotrod shops have. This was an electric fan retrofit on a 4x4 that previously had a crank-driven fan. It fried way out in the corn one rainy night and the next day I went to work with a diagonal cutters removing mangled knots of melted wiring. I can still see the blades windmilling on final approach into the dumpster.

P.S. as a stop-gap, when the temp climbs in traffic, I flick on the defroster which pulls in the A/C compressor to knock down the moisture. Just gotta remember to shut it off before you pants the V6 Camry next to you so as not to over-rev the compressor.

 

I use a Mr Gasket 195 degree stat. It is designed to be completely open by 195 as apposed to factory 195 that starts opening at 195. Seem to work good for me. At cruise speeds temps average about 190.

 

My 89 gets up to around 235 before the fans kicks on, hence the reason I am putting in a new chip to kick the fan on at 195 and shuts off at 185, the chip was programmed by ski_dwn_it (aka Jesse) with a few performance mods too... My friend is unsoldering the old chip and putting in the zip socket tomorrow...

 

[QUOTE] .
I can still see the blades windmilling on final approach into the dumpster.

[QUOTE]

:lol: :lol: :lol: .
Once again experience is the best teacher..
Thanx for the dumpster line (been there done that)

 

I speak from real world experience. My 94 ran up to the limit regularly ie 228degrees the fans come on. That is a bad thing. I removed the radiator (good days work) cleaned it very thoroughly. Temp seldom goes over 188 now. Best thing I ever did for my car.