How hot is hot?

[tn2]

My 78 Argosy seems to be running hot. I installed a new temp gauge and it is still reading pretty close to what the old one was. After about 10 minutes of driving the temp will go up to approximately 215. For troubleshooting purposes I took the thermostat out and it still goes to about 215. The thermostat I took out was marked 160 degrees. Now I know these big engines (454) need to run lots warmer than one might think is good....also know that antifreeze boils at a higher temp than water ( i.e. higher than water's 212) but is 215 too high. Temp gauge is the only indication I'm going by....by that I mean I notice no effect on how the engine is running....no pinging....starts up good after shut down. Thanks for your input
Charles

[klattu]

Mine hit that range at first start up for a while.
Was the cross over valve in exhaust sticking.
Like yours, it ran fine, just warm.
After working it free, never goes above 200^ now.

If yours is stable at 215^...
Could be just gauge reading, or sending unit.

[guy99]

Originally Posted by tn2

My 78 Argosy seems to be running hot. I installed a new temp gauge and it is still reading pretty close to what the old one was. After about 10 minutes of driving the temp will go up to approximately 215. For troubleshooting purposes I took the thermostat out and it still goes to about 215. The thermostat I took out was marked 160 degrees. Now I know these big engines (454) need to run lots warmer than one might think is good....also know that antifreeze boils at a higher temp than water ( i.e. higher than water's 212) but is 215 too high. Temp gauge is the only indication I'm going by....by that I mean I notice no effect on how the engine is running....no pinging....starts up good after shut down. Thanks for your input
Charles

As Klattu says, if you haven't replaced the sending unit you may not be getting an accurate reading. You could try one of those laser/infrared thermometers on the inlet housing. Mine runs ~185 unless under load in the heat, then maybe 205. I don't know what gauges your rig has but mine has teleflex and I didn't get an accurate reading until replacing both gauge and sender. These guys were very helpful in getting what I needed. Home Page

[GlenCoombe]

Not to state the obvious but if the temp reads the same without the thermostat in ...have you checked the operation of the thermostat?
Replace it with a new unit just to be safe. See what happens... make sure it's in the right way up too.

[tn2]

I did buy a new thermostat but haven't put it in yet. It seems to me that without a thermostat installed you should (theoratically) have way too much cooling. In my case....without the thermostat there was no change in temp....still ran at same temp. I would think that would indicate one of two things...ether the indicating system is wrong or something blocking the cooling capacity of the radiator. I can imagine a flush job is in my near future.

[Fyrzowt]

Originally Posted by tn2

I did buy a new thermostat but haven't put it in yet. It seems to me that without a thermostat installed you should (theoratically) have way too much cooling. In my case....without the thermostat there was no change in temp....still ran at same temp. I would think that would indicate one of two things...ether the indicating system is wrong or something blocking the cooling capacity of the radiator. I can imagine a flush job is in my near future.

You can actually have less cooling because the coolant flows through the radiator too fast to dispurse the heat.
Dave

[tn2]

Well Dave that's sounds like a good point.....never though of it that way. I did some reading in my chev chassis book...it says... a 15 pound test radiator cap raises the pressure inside the radiator which in turn raises the boiling point of the coolant. With a 15 pound cap the coolant won't boil until 262 degrees. So I feel a little better with my 215 degrees. I will get a new cap tomorrow to make sure it's good. Thanks all for your input

[ROBERTSUNRUS]

Originally Posted by Fyrzowt

You can actually have less cooling because the coolant flows through the radiator too fast to dispurse the heat.
Dave

Hi, this statement is correct. Many years ago, I went to General Motors School and coolant temperatures were discussed. Basic theory: Water boils at 212 degrees, Add three degrees per pound by pressure cap, and only while under pressure and with a proper 50/50 mixture of coolant and water, you can add about 30 more degrees. So water boils at 212 degrees, add 45 degrees for a 15lb cap; That gives you 257 degrees. Now add proper mixture of coolant and water [50/50] add another 30 degrees and you end up with a total of 287 degrees. Most Fords with electric cooling fans turn on at 220 degrees. Engine temperatures between 190 and 220 are normal and you are safe all the way up to the point just before it boils over. Once coolant boils over and into the street, now you are in trouble. At 215 degrees, you are worried about nothing. Chevrolets, in the 70s, turned the overheat light on at 262 degrees.
One more thing: It's better to use distilled water than tap water especially if there are aluminum parts in the cooling system. [intake manifolds, cylinder heads, radiators Etc.]

[FreshAir]

I have run and towed with Buick 455s for 20 years. They do have a tendency to run 'hot' under a load but if it doesn't boil over you are ok. However, I did have boil overs a couple of times and after a lot of head scratching because all the cooling needs where met. Improper distributor advance was the problem in each case. Those powerfull big block engines can not be advancing as it should and 'appear' to be running fine. So check out your distributor (vacuum) advance.

Neil and Lynn.

[tn2]

Thanks for all the good advice...I will rest a little easier....
One other thing I noticed in my reading....it says that nothing should be placed in front of the radiator. Well of course that makes good sense,, but I noticed that either the manufacture or PO has installed the radiator overflow bottle right in front of the radiator....not only that but they used a rather good size piece of aluminum to mount the bottle on. I was wondering if anyone else has seen this on their RVs. This article that I was reading was put out by Chevolet and they even said that if you're installing wire mash as a bug catcher in front of the radiator the mash should be bigger than standard household screen wire because that fine of mash can contribute to overheat. Makes a believer out of me that can't be too concerned about airflow.

[doorgunner]

OOPs sorry I thought this was about hot wings that you get at that place, whats the name of it oh yea "Cooters" isn't that it? sorry for the hijack