Lastspark

Hopefully this is the right place, and I feel dumb for asking such a simple question. But my temp gauge is reading pretty high. Here's some details.

Engine: 383 stroker, mild cam, freshly built and finished 5 days ago. It is indeed carburated.

Radiator: quad core aluminum

The car is a 94 Camaro, I had a 383 in it before (it started knocking pretty bad so I rebuilt the engine and put in a bigger cam and had a port and polish done). My old 383 could keep cool pretty well, stayed between the middle line and the next line up on my gauge. So basically the problem is it gets hot, but not as fast as it would if say the coolant was low, or the coolant was bad. I did a 50/50 mix. The radiator cap seals but there is a hole right under where the cap goes that you would plug a overflow line into it. Well I removed the overflow tank a long long time ago to make room for a deep cycle boat battery so I didn't have any problems with batteries going dead at a drive in theatre ;p. But I never plugged the hole, and in the past it didn't overheat or anything. But now with the new 383, it's overheating. The only thing I have changed is I don't have a thermostat and I bypassed my heater core since I removed the fan controls to mount in toggle switches to start the car since my key ignition went bad (Just had toggle switches sitting around, seemed like a good idea).

So today it started overheating, I put a plug with some teflon tape on the threads in the hole, still got really hot, as in was well on it's way to the red line of the gauge. So I took it out and checked the cap, drove it and it still got hot. I thought maybe it was a air bubble in the coolant flow. But I had a air bubble in my BMW and it would overheat quick, and my Camaro takes a trip from here to the grocery store and halfway back, which is about 10 miles of red lights and 90 year olds driving 20 in a 50, to get between the last white line and the red line of the temp gauge.

Sooo... would putting in a thermostat fix this? Or maybe running the lines to the heater core again fix it? I popped my hood at a red light and let it just be latched by the saftey latch and I was going about 30 or so and the temperature went down a bit. And since Camaros are bottom feeders, should I find a way to get more air to flow into the radiator maybe?

Sorry for the wall of text, just tried to be specific and include my thoughts as well as what I have done and compare it to the previous build of the car.

2wd-K5

what is the condition of the rad? is there visible blockages through the cap? (looking inside the rad), also, did you remember to punch out the steam holes in the head gaskets? not only these, but 1 time i had my valves set up wrong (too tight, beginner error) and it got hot as soon as i juiced it and stayed hot, also, i would run a t-stat, just for good measure

therewolf

Hi Lastspark,

Welcome to the Chevy Forums.

Overheating is an issue for many, and your questions are welcome. Don't be shy, share your experiences so others may benefit and save money here. That is what we do, and the more the merrier.

First, many people mistakenly think water in the antifreeze is a cost-saving measure. Nothing could be further from the truth. Most racers run straight water, or a much higher proportion of water to antifreeze, because water efficiently transfers and dissipates heat, whereas antifreeze only keeps the water from freezing.

So, if anything, with a hot mill, 60 or 75 % water in the mix will mean a cooler engine.

Radiator caps are largely ignored, but an old one will form a set at the gasket and leak, allowing system pressure to drop from 14 PSI to 0,= OVERHEAT.
For the cost of a good cap(8$?) just replace it if it's a couple years old.

As to the thermostat, what it's really doing is holding the water in the radiator so it can cool while the engine heats the water in it's cooling jacket. A constant flow of water in many cases is just going to circulate the water through the radiator too quickly too cool it down enough.

Missterry

Same thing was happening to mine, long story short, it was the water pump, not the temperature sensor relay ( although I replaced that as well) but if you do not bleed the valve (relay) on the radiator it will continue to over heat. The Water pump was not out, but so jammed full of hard water deposits that it was unable to circulate water properly. Hope this helps.

Missterry

oh yeah, I started with all the small things first, thermostat, radiator cap, hoses,relays. But sad enough, it was the pump.

Lastspark

Thanks for all the help everyone, turns out the ohm difference of the water temp switch/sensor thing that screws into the side of the block was providing a different reading to the stock computer I have in the camaro that is only still there for the stock gauges to work. I noticed I could let the car sit over night, start it up at 5am and the temp gauge instantly read about 180 degrees and just went up from there. Took a temp of the front of the rad with one of those badass infrared temp guns and it read about 90, drove the car till the temp gauge hit the red line and took the temp again and it read about 160. All temperatures in F.