Cooling Issues

Just finished new motor install, has about 5 miles on it. Also installed water temp guage replacing stock sender in original location (black heater line). A few issues with the cooling system...

Water Temp guage is reading real hot, gradually increases up to 230-250 degrees (just idling in the driveway) before I shut it off. Electric fan isn't turning on at all so I know that will help the issue, but probably not solve it, right? So I need to re-wire the fan and get that going again. Had a 160 thermostat in there, figured I would eliminate variables in case it was bad, so put in a 195 degree (stock)... didn't help. Water pump is brand new.

Any suggestions on what to do / what to check? Is it possible that the temp guage reading is just coming in innacurate / too high?
 
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Upgraded to a heavy-duty radiator a few years back. Forget if it is dual core or 3-core, but it is definitely thicker than the stock one. Had to bend the brackets out to hold it in place.

Good suggestion though, that's why I got that one in the first place; car was running too hot after H/C/I install and it did the trick. Think its a "BeCool" radiator if my memory is working.
 
If you put the gauge sender in the heater line, you removed your ECT. Put the ECT back and put the sender for your new gauge in the stock 'gauge' sender location (front of the lower intake, driver's side). The gauge sender has one wire going to it. The ECT has multiple wires. Again, put the ECT back in the stock location.

If you're just idling, you need to have the fan functional. Otherwise no air moves across the radiator.

Good luck.
 
When I pulled out the sender (or ECT) from the heater line, there was only one wire going to it. And the unit looked very similar to the new autometer sender. On the driver's side front lower intake, there are just the two snap in connectors. I think an air charge sensor and one other sensor. Since I switched the stock sender (or ECT) the stock temp guage does not budge at all. Is it possible that my car has a different stock sender location/setup (87 GT)?
 
Someone hosed with your stuff already.

The ECT is a sensor (multiple wires). The gauge uses a sender (one wire).

So your ECT is in the driver's side lower intake (where the stock gauge-sender should be)?


So you do not have the stock gauge sender connected to anything, right? And the gauge doesn't move? It should not.

Your aftermarket gauge is functioning correctly, right? You just need to get the fan functional.

FWIW, this diagram (courtesy of Tim, Stang22) might help show how things should be.

http://leemotorsports.com/almoststock/50enginepartsguide.jpg

Good luck.
 
Oh ok that helps. I had the ECT and the ACT sensors on the driver's side with the guage sender on the heater line. I'll switch the ECT and guage sender back to where they should be.

The new temp guage is definitely operating, just not positive it is operating correctly. Is it possible that the guage is reporting the temp too hot?

So it sounds like i really need to get that fan going and give it another test at idle to see if that solves the problem. I was thinking there was a bigger issue at hand but hopefully that will do the trick.
 
If it takes a little while to get up to temp, but then simply keeps creeping up, it's likely just not having a fan.

If the readings go up and down really fast (faster than one would think possible), there might be air in the system. And if it's an electrical gauge you installed, the temp sender needs to have continuity to ground. The use of a lot of thread sealant can hinder that. If you have a DMM, set it to low-scale Ohms. Put one lead on the sender body (like the hex head you use to tighten the sender) and connect the other lead to the negative battery post. You should see under 5 Ohms.

Good luck.
 
If it takes a little while to get up to temp, but then simply keeps creeping up, it's likely just not having a fan.

If the readings go up and down really fast (faster than one would think possible), there might be air in the system. And if it's an electrical gauge you installed, the temp sender needs to have continuity to ground. The use of a lot of thread sealant can hinder that. If you have a DMM, set it to low-scale Ohms. Put one lead on the sender body (like the hex head you use to tighten the sender) and connect the other lead to the negative battery post. You should see under 5 Ohms.

Good luck.

:Word:
 
Alright back for an update, coolant temp is still getting way too hot. So around 7am it was 60-70 degrees outside and the car was able to idle in the driveway stuck right where it should be @ 195 degrees (thermostat temp) for about 15 minutes. Later in the day took the car out for about 10 miles when it was 90-100 degrees outside. The coolant temp gradually got up to 195 then stopped for a minute or two, and continued to rise up past 230 while driving.

Electric fan is working great now and thermostat is definitely working properly. I know for sure that the guage is giving an accurate reading because the temp goes up and stops @ 195 right when the thermostat opened. I jacked the front end of the car up and let it run with the cap off for a while, definitely burped and full with coolant/water. overflow tank is filled about half way. replaced the radiator cap. At this point I am running out of ideas.

The ONLY other variables I can think of since new motor install would be:
-no side air deflectors in now, haven't had bottom deflector since who knows when.
-AC condensor is in front of radiator now (just sitting there; not operating). Could either of these be causing problems?

I am on the verge of going back to the stock fan blade, clutch, shroud setup. When I look at the flex-a-lite electric fan (#185) it covers max 1/2 of the surface area of the radiator and has no shroud. Never was a problem before but maybe now?

Any help would be great, this thing is becoming more and more frustrating.
 
If your using a Black Magic fan on a 331 that probably isn't enough fan to cool your car (assuming from your post and sig). Might ought to try a Taurus fan or a Mark VIII fan.
 
Yea I'm thinking the flex-a-lite electric fan has to be the weakest link at this point. Just want to make sure before I switch back... always though electric fan was an upgrade. I've always seen talk about the Taurus / Mark 8 fans but never looked in to them. Big upgrade from the stock setup?
 
If it also runs hot while at speed, I'd put an air deflector on (there's no grill so air needs to be sourced and circulated through the coil somehow) and see if it then runs cool at speed.

If you can get it to where it runs cool at speed but not while idling, then you can start to make guesses about the fan. If it runs hot at all times, you're just guessing at the cause.
 
180 thermostat and all 3 radiator air deflectors are now on the ToDo list. Not too confident that those will SOLVE the problem, maybe just HELP it...

So if the black magic fan is coming out, would the stock fan/clutch/shroud setup be recommended? Or do the Taurus/Mark VIII fans have a lot more cooling power? Or do people usually just upgrade to Taurus/Mark VIII to have an electric setup? I am just suspicious now of the power of the black magic fan, looks like with a measly shroud and small surface coverage it might be causing the high temps, even while at speed.
 
The Mark VIII and Taurus are an upgrade over stock, especially worn-out stock stuff.

While at speed, the fan does not have much function. This is why many OEM fans shut off at 40+ MPH.