The Stovebolt Site Forums The Shop Area Engine Shop hi temp on 292

the ole saying "if it ain't broke, don't fix it" must apply here. doing some clean up in the engine compartment and pulled the radiator to clean up the tank, replace the hoses etc. One thing led to another: replaced all the hoses, thermostat, temp sensor in thermostat housing, heater core, new water pump. Everything is back up and running smoothly 'but' reading on temp guage is sitting on the high side of the guage. Replaced the new sensor and new thermostat with more new. Still reading on the high side... First question I ususally get: "is the thermostat in correctly??" and yes it is. Used a white heat sensor around the block and associated hoses, temps registering between 190 and 200 degrees. Not getting any overflow from radiator, no boiling over. Any suggestions, recommendations. Thermostat is 180 degree......Rx/CTOCS :confused:

trex: when you said "clean up tank" did you clean inside and outside? did you force dirt into fins or did you paint and get fins to full w/paint slowing down air movement?

popcorn Thge Truth is Out There (Good luck keep us posted)

What temperature is the thermostat? It almost sounds like you've got a 195 degree stat in there and everything is working as prescribed.

My new temperature sensor unit caused my temp gauge to peg out at the top just after warming up. I put my old one back in and it worked just like I expected,low to medium with my 185 degree thermostat. The new aftermarket sensor just didn't register correctly.

flushed the radiator.... basically removed the paint from the upper tank and shined the brass.... washed down the fins on the core and put a light, very light, coat of flat black spray on it just to dress it up..... both thermostats I've put in have been 180's.... if I hadn't misplaced the original temp sensor I'd put it back in and see if that helped.... thing doesn't overheat.... just showing on the high side on the temp guage....Rx/CTOC

What type of fan do you have on the engine OR on the radiator?
Is it the stock 4-blade fan?

Still have the stock 4 blade fan in place.... Switched to another new sensor tonight but haven't fired it up yet to see how the temp is going to do..... Rx/CTOCS

First, check the thermostat. Suspend it in a pan of hot water on the stove. A tall pan, dowel rod and string usually works. It also helps if the thermometer is suspended, too. Heat until the thermostat opens, I would bet you have one that is too hot.
Also, regular spray paint inhibits heat transfer. Eastwood sells radiator paint. Bad part is you have to boil the tank to get the paint off.

trex, I know where you're comin' from, things like this bug me too. It's not overheating but, it's not as cool as it was (or does not appear that way). A couple months ago I changed most of the parts you changed on my 65 with a 230. Didn't make much difference in temp UNTIL, I swapped the stock 4 blade for a nice 6 blade and added a fan shroud which P/O had removed. The spacer I got put the fan nice and close to radiator. BIG difference. She's ready and steady even when sittin' in traffic under the California sun.

You may not have the right mix of antifreeze.
Too much glycol will bring your operating temp up.
Did you use a 50/50 mix of coolant/water?
The warming ambient temperatures will exacerbate
this condition.

JS

Thanks for the input... Still working on the problem just had to take a few days away from the garage for a school district science fair... Got to take a look at the fan... One of my friends (?) asked if I had the fan in backwards... Got to get back to the garage in the morning.... Anti freeze I put in said to use a 75/25 mix.... Never drive the thing in rough weather so going to pull the thermostat tomorrow and see what affect that has.... Got to be that darn sensor... could kick myself for losing track of the old one.... Rx/CTOCS

Anti freeze I put in said to use a 75/25 mix

This has got to be your problem.
Check the container. If it says 100% glycol, you need a 50/50 mix. I don't care what the container says about mix ratio. If you put a 75/25 ratio in, you're definately going to be running on the upper range of operating temp. I'm willing to bet, if you put a 50/50 mix in, this will correct your problem. You could just drain out a gallon, and, add a gallon of water.
See if it works.

JS

Checked the mix on the anti freeze... list mix at 50/50 minimum and 70/30 maximum.... lightened my mixture but haven't had a chance to get it out of the garage to fire it up.... Tks.. Rx/CTOCS

I think you found the problem with the antifreeze. When you go more than a 50% mix, you start loosing cooling efficency. Anything over 70% is horrible on heat transfer. If you're in an area where the temp drops below -25F, use the stronger mix, but only in the winter. And a 50% mix, which should show about -34F on your antifreeze tester, is recommended for limiting corrosion.

Well guys the 65 C-10 is back up to snuff.... Took it out for a spin today and no high temp probs what so ever... Thanks for all the input... I did end up pulling the thermostat.... Pickup doesn't usually make it out in inclement weather anyway.... Thanks again....Rx