Motor running hot? 210 Degrees!

[rlm316]

I agree completely with the timing issue. I run Pontiacs and the timing has to be just about dead on or they run hot. Also check your fluid level in the rad. Water boils at 212*f or 100*c at sea level. Glycol with the pressure will raise the boiling point. If the level is low you may be getting steam pockets in your cooling system and that is where the rumble is coming from. Whatever you do, don't touch the rad cap until that thing settles down. I've seen coolant come up out of a rad like a geyser, hit the underside of the hood and cover the poor guy trying to add water to his rad. That leaves a pretty good mark that you don't forget too soon even if you are only a spectator. Good luck.

[WorkinLonghorn]

OK, I read all this and had some thoughts.
210 is not too crazy, but if you hear it "boiling" inside the motor, your flow may be restricted somewhere. Antifreeze is just that... it keeps the fluid from freezing in the winter, but it doesn't conduct heat as well as water. Thus the recommended 50 percent mix. You might also check your timing... I've had them run hot when it was close but not on. Does it knock a little before shutting off?

This is correct Hottlube,good post. If you run 100% anti-freeze it will run HOT.Timing AND fuel mixture affect temperature.Too lean=hot.Also check that the lower rad hose isn't collapsing.That's why there is a metal coil in them.The metal rusts away (if run with insufficient antifreeze/rust inhibitor) and the hose collapses causing poor flow,overheating.O.P. mentioned damage to the radiator.Sometime a shop will simply seal off the affected rows and of course this cuts down on the cooling efficiency .

[Overkill67]

1 more thing I didnt see mentioned. I know these puppies did not come with fan clutches but if you happen to have one (some people think they are a good Idea lol) that may be the problem in itself. If you do have one and the goofy thing goes bad it will cause it to run hot, because it does not engage the fan at speed. My '72 C30 HAD one until about 30 minutes after it hit the driveway

All the rest that everyone else mentioned are things that should be checked as well.

[chvtrkman]

I was doing a search on timing issues and saw this old thread....I thought it wouldn't hurt to add a comment.

For you guys with the inline 6 (194,230,250,292)....

My truck was running hot. I installed a new water temp. gauge. After warm up the gauge was reading 225 at idle. I thought many things could be contributing to this. I also had a minor leak in the radiator. I wasn't losing a whole lot of coolant but the rad looked shot to me, so I said why mess around, and just ordered a new one.Also replaced the thermostat. After intsalling it the 292 still ran hot...220 degrees. I moved the location of the sending unit from the cylinder head to the thermostat housing. The water temp is higher the closer you are to the combustion chambers. Problem solved. Engine now runs right at 195....right where it's supposed to be.

[EAST SIDE LOW LIFE]

Originally Posted by chvtrkman

I was doing a search on timing issues and saw this old thread....I thought it wouldn't hurt to add a comment.

For you guys with the inline 6 (194,230,250,292)....

My truck was running hot. I installed a new water temp. gauge. After warm up the gauge was reading 225 at idle. I thought many things could be contributing to this. I also had a minor leak in the radiator. I wasn't losing a whole lot of coolant but the rad looked shot to me, so I said why mess around, and just ordered a new one.Also replaced the thermostat. After intsalling it the 292 still ran hot...220 degrees. I moved the location of the sending unit from the cylinder head to the thermostat housing. The water temp is higher the closer you are to the combustion chambers. Problem solved. Engine now runs right at 195....right where it's supposed to be.

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This makes a lot of sense and can be over looked quite easily searching for a more technical reason to solve this problem. I have new hoses, New rad, tested the thermostat it's fine, and replaced temp sender unit new. Not to mention I have a new temp gauge under dash and I get a reading of 210f. This is at speed or idle the reading is consistent so I've not been too concerned but I'm checking my gauge a lot. Water boils at 212f at sea leval and I've yet to boil over. I never replaced these parts because of this they just needed to be replaced. So I guess if I had replaced these parts because of my truck running too hot I'd be quite frustrated at this point. I'm going to swap locations and see if it will make a difference to my temp. reading.

Oh yea .... Never boils over.
esll.

[corn]

210 isnt a big deal. Most GM cars in the late 70'-early 80's ran in the 220-240 range. That high always bothered me a little...

[WinDancer]

I have dual electric fans on my 396. When you turn the motor off, and the water is no longer circulating, the temp absolutely climbs. All that heat in the block has to go somewhere. It took me a while to get used to the fan coming on after I turn it off and get out
I checked the place where I bought the fans and the owner took me for a short ride in his truck and it does the same thing.
A couple million years ago, when I was in high school, the common talk was that you wanted any gas engine to run as close to 211 as possible. Back then it was thought that hot engines ran better with more power and better mileage.
If you aren't running electric fans you are leaving the engine on its' own when the temp climbs after turning it off. I would probably drop down to a lower temp thermostat to prevent boil-over after stopping the engine.
Just my .02