Operating temperature

Can someone tell me what the operating water temperature of a

1989 350 Chevy Silverado 4 X 4 with auto trans is? The repair shop replaced the thermostat and now my temp reads 220 degrees. This seems high to me but they say that's what it calls for.

Thanks, Joe.

Reply to
Joe Lojek
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What was it reading before they changed it? The thermostat only opens at a specific temperature. It doesn't regulate the temperature. So in order for it to run hotter now than before there has to be a change. If all that was changed was the thermostat then all that it could be is the flow of the coolant is either faster or slower than it was before. Either can cause a temperature change.

Brian

Reply to
el Diablo

Hmmm....I've argued this one before. *Of course* a thermostat regulates the temperature. What do you think it's there for? If a thermostat cannot regulate the temperature, there is something wrong with the cooling system, whether it be inefficient, not large enough, or not enough air flow through the radiator.

Ian

Reply to
shiden_Kai

I wouldn't necessarily trust your dash gauge to give you an accurate reading of what the temperature really is. Usually, with a 195 degree thermostat, that's what you will see, providing there isn't any other problem with your cooling system.

Ian

Reply to
shiden_Kai

I agree Ian, if the system is designed right etc. the thermostat opening at a set water temperature should in fact have set the running temperature. But even driving conditions will raise or lower the temperature due to coolant speed in the system. The coolant hast to have sufficient time to absorb the heat from the motor etc.

Long story short if all that were changed was the thermostat it's probably opening at an incorrect temperature or something else changed as well.

Brian

Reply to
el Diablo

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180 to 195.

Thermostats are hit and miss, unreliable suckers.

Have it changed again.

HDS

Reply to
HDS

The thermostat has no bearing on the running temperature of the vehicle. It only opens at a specific temperature. Even if the thermostat opened at 220 degrees the temperature would settle at 195 degrees if the cooling system is functioning correctly.

1: He said it ran at the right temperature before the thermostat was changed. 2: If all that was changed was the thermostat then there would have to be either a restriction in the flow or not enough restriction (not likely).

We don't have enough information to diagnose the problem. Like why was the thermostat replaced? Did the motor overheat severely prior to this repair work?

Brian

Reply to
el Diablo

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The Question was: "> > > Can someone tell me what the operating water temperature of a > > > 1989 350 Chevy Silverado 4 X 4 with auto trans is?

Again... 180 to 195.

HDS

Reply to
HDS

Please add a little more explaining as to how "Again... 180 to 195" will fix his problem.

Allow me: Again... The thermostat does not control the running temperature of the vehicle. Only at what temperature coolant is allowed back into the radiator.

Reply to
el Diablo

Brian, think about what you are saying. You are saying that if the thermostat kept the fluid circulating in the engine block (not allowing it to be cooled by the radiator) until the temperature reaches 220 degrees, that "somehow" the temperature of the engine will "settle" back to 195 degrees. That's not possible.

You also keep repeating your mantra about the thermostat having "no" bearing on the running temperature of the engine! Of course it does (as I already said)! Since I've already had this argument before, let me nip any of the stock excuses in the bud. Any stock cooling system should be able to keep the coolant temperature "at" the thermostat opening temp. If not, then the cooling system is poorly designed, or there is some sort of problem with the cooling system, probably related to air flow. But if you have the proper air flow, the thermostat "will" regulate the engine temp. If your fans aren't working, or you are sitting in traffic and you have electric cooling fans and the a/c isn't on, if you are low on coolant, if you have a restricted radiator, if the radiator fins are plugged up....and on and on...then yes, the thermostat may not be able to regulate the temperature. But when we are discussing this issue, the assumption is that "all other things being equal", the t/stat controls the temp.

It probably is something as simple as a bad t/stat. It's certainly not unheard of, I've seen dozens of them.

Ian

Reply to
shiden_Kai

Joe Factory temp gauges are notoriously inaccurate. I'd hook up a mechanical temp gauge and see what the temp really is. The thermostat controls the minimum operating temp while the radiator controls max temp. So, if everything works right, a 195 degree stat should keep the temp at *about* 195 degrees. If I am wrong, I'm sure Marshy will let us know :-). H

Reply to
Hairy

The cooling system is operating properly, the old thermostat was 180 degrees and was replaced with the new one to take the temp up to 210 degrees. My question was what is the factory specs for the proper operating temp. Now since my last post I drove it and the there is a noise when I feed gas. It sounds like valves rattling when you put in cheap gas, but no gas was installed since before the change. New question, will high temp make that noise. The timing was never changed. I don't want to harm the engine. I want to thank all you who replied for this.

Joe.

Reply to
Joe Lojek

My Stant book says you should have a 195 degree stat pn 45359 H

Reply to
Hairy

My motorcycle has a digital temp readout, so when it moves ever so slightly, I can see it. When a turn the bike on after sitting all night, it reads "---" until it gets up the the minimum thermometer temp of 68. While I am cruising down the street it reaches 195, I feel a harm blast on my legs, and I see the read out go from 195 to 185, then the warm blast stops, then it climbs back to 195, another warm blast, down to 185, then it stops again. Clearly, like you say, the thermistat is opening and closing to maintain a

185-195 opperating temp. When I hit a red light, I just sit there and idle (no air movement) the thermometer just keeps climbing past 195, past 200, past 210 (long light!) the cooling fan kicks on around 220 I think. Once the light finally turns green, I start moving again, and the temp drops down to 185, then bounces from 195 to 185 as the thermistat opens and closes. Coming home from Palomar, Via the 15 through lake Elsonor, my bike was fully loaded, and it was about 105-110 degrees out, I was cruising at 80 mph, and the temp was 202, if I sped up, the temp would climb, if I slowed down the temp would drop a little. but it stayed as steady as the speed since the bike was making as much heat as the cooling system could cool and the t-stat didnt open and close, since they were both balanced, the t-stat just stayed open.
Reply to
Trey

You don't need a thermostat that makes the engine run at 210 degrees. Just go get an OEM thermostat, which will be 195 degrees and use that.

Ian

Reply to
shiden_Kai

What kind of bike do you have?

Reply to
Mark

Exactly, and that's how the thermostat controls the "running temperature" of the engine. It's actually a very simple concept, and I'm always amazed that some folks on these newsgroups don't get it. Cooling systems 101 and all that!

Ian

Reply to
shiden_Kai

Right...and I think that it might be safe to say that your cooling system "at that speed and load" is right on the edge of marginal. But overall, it appears your bikes cooling system behaves very much like a late model car with electric cooling fans.

Ian

Reply to
shiden_Kai

OK we're on the same page now. I wasn't thinking the entire process through. My apologies to HDS.

Brian

Reply to
el Diablo

With the heat blast I was going into, -I- was over heating! the bike was doing fine. 650cc v-twin, me, saddle bags, tail bag, all full, head wind, and about 105-110 out. Aparently, the cooling system only has 3.6 pints of coolant/water in it. the manual says that if the temp gets past 248f, an idiot light will come on telling you to stop and let it cool, and if it reaches 284f (TWO HUNDRED EIGHTY FOUR!!!) the display where it shows your speed will blink "HI" So running it at 202 or 210 even, is not really an issue for the bike. I dont want it to get that high, but its nice to know it can. Plus, bikes are not made for a big load (like towing) so I think the cooling system is sufficient for 99.9% of my riding, any bigger and it becomes extra weight. The bike is only 375 pounds.

Reply to
Trey

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