Still running too hot

[qposner]

Well, I got my leak fixed, but my 79 is still running too hot. I have bled the system, installed a new tstat, new water pump, recored the rad, new heater core, new hoses, 50/50 water/coolant. Today was 65 degrees and overcast when I ran it around for 10 minutes or so. I got the temp up to about 195 when running lower revs (4th gear, 35mph or so) and it would run 180 most other areas. I did not get on the freeway. My problem is prior to all of this, it would ALWAYS run 180. Why 195 now?????? I don't think it is my gauge as it was registering 180 just prior to the replacement to new coolant parts.

Now, I have heard a suggestion of a 160 degree tstat, but won't it still run up to 195 degrees, just take longer to get there? Also, I must have a 180 tstat (not 195) because the car will stay at 180 when reved a bit with air running through (fan and air of speed, around 45 in 4th). Any suggestions for me? This is getting frustrating.

BTW---When I squeeze the top rad hose, I can bring the two sides of the hose together and hear a slight sloshing of water/coolant. This seems to indicate air in the top hose. Thoughts? What is the best way to rid this air since it is highest up?

Thanks,
Quinn
Frustrated in The 'Couv

[Gubi]

195F is hot? I mean, for Greenland maybe, but for a car engine it sounds pretty darned normal.

My radiator hoses on almost all of my cars have sloshed when I've squeezed them. I wouldn't take that as a sign of air in the lines - you're just moving the liquid around.

[Roadtrip]

Quinn -
Check the bleed one more time now that the car's run awhile. Otherwise, I think you may be chasing a problem that's not there. Maybe there's a slight indicator problem with either the gauge unit or sending unit. Have you checked the electrical connections clean and tight? Take it out on the highway and run it at 70 mph or so and see what the temperature does. It'll probably rise to 200-205F or so, which is normal. Do not put a 160F thermostat in the car if you have the SPICA injection system still installed.

Confirm that you have the stock fan (and that's it's installed to suck air through the radiator) and the fan shroud in-place.

[John M]

Another thing to consider.....the gauge could just be off or its sender. In any case, like RT said....these are fairly normal temps. If you start hitting above the 212 mark....its time to really investigate everything you have touched and go through it bit by bit.

Best Regards,
John M

[JoeCab]

I agree with John, if you put a 160 degree thermostat in your car it will run too rich, decreasing both performance and mileage.

JOe

[qposner]

My concern is that this car ran dead on at 180 for 25 years. The gauge read 180 (while driving) right before I replaced everything, so I doubt its the gauge. I don't think I should accept 195 as a temp since this car was at 180 with a 25 year old coolant system. With everything updated, it should still run 180. Thoughts?

Roadtrip: I installed the fan back in the way it came out, so I would think it is functioning properly. As for the fan shroud, I left it out. However, I have since reinstalled it by cutting it in half and working it into place (although I did cut a portion of the bottom off). I now wish I had just installed it when the rad went back in, but it was nearly impossible to get everything in and I did not think it would be necessary. When it started running hot, I figured it needed to go back in, but I did not want to drain the system, remove the rad again, etc so I cut it in half.

Also, where would I locate the temp gauge connection and sending unit?
Quinn

[John M]

Hey Quinn:

The temp sender is located on the intake manifold next to the bleeder. It might just be the cut shroud. Also did you remove the air dams around the radiator opening. Should have a dam that runs across the top. And seals around the sides to keep air from recirculating or bypassing the radiator core around the sides of the radiator.

Best Regards,
John M

[qposner]

Do you mean the black strip that sits on top, just forward of the rad? It has a slot that allows it to sit on a strip of metal from the body? If so, that is there.

As for side seals, I do not recall removing anything (or seeing any for that matter). Where should they be located?

[John M]

Hey Quinn:

Yes...on top there is a metal piece that screws into the upper radiator support and catches the top of the radiator. That is the upper piece. Then along the sides of the air box leading to the radiator should have seals running vertically. These press up against the radiator when installed....essentially sealing the air box to the perimeter of the radiator. If they were already missing...then likely not the problem. Shroud is the one thing that is not put back as it was prior to removal.

My best bet on the entire senario....the tstat you have from IAP doesn't open as early as your old one. They may call it a 180....but my spider with their tstat also runs a tick above 180. 195 is just a normal temp. Beyond 212 is where the concern starts to mount. So don't loose any sleep over this at all.

Best Regards,
John M

[qposner]

What about the temp fluctuating? I would prefer it just sits at one temp w/o changing. The fluctuation suggests something is amiss (at least to me anyhow).

Thanks for all of your input. RT, I will try bleeding it one more time.

[Roadtrip]

Did you install the t-stat with the actuator pellet "down" (with it in the manifold coolant and NOT towards the radiator hose)? I'm not sure you can install it wrong, but you might be able to?

Do you still have your old t-stat? If so, test it in a pot of heating water and reinstall it if good. Does your t-stat have the extension and blockoff for the warm-up coolant bypass?

BTW, cutting up the fan shroud was a dumb idea. I'd recommend that you get a new one, then install it correctly. If the ends of that thing get loose and go into the fan blades, it can fragment a blade which can hole your radiator. I'll bet it makes some real expensive sounding noises when that blade lets go.

I think they're about $25.

[qposner]

Duly noted on the shroud. I did it because I saw an example here which made it look easy to remove and reinstall the shroud. I will order a new one, drain the rad, remove it, install the new shroud, and reinstall the rad.

Live and learn...

[John M]

Quinn:

You will see the temp fluctuate with the opening and closing of the T stat....especially during warmup. Maybe 5-10 degrees. You have the temp sender right there near the tstat. So you should see a drop as the tstat opens and closes. Here is a thing to do. Let it sit until its cold. Start the car. Watch the temp gauge as the car warms up. Watch for the first big drop on the gauge. High temp will give you when the tstat is opening. Low temp will give you the range on the tstat. Even after she is warm and going down the highway....you will still notice a slight fluctuation.

Best Regards,
John M

[alfa63]

Quote:

Originally Posted by Roadtrip I'll bet it makes some real expensive sounding noises when that blade lets go.

[gvisconty]

I had a very similar problem (on a 73 GTV). I finally tracked it down to bad (flakey) ground connections at the dash board. Indicated temperature increased as resistance between the dash and ground increased, and vica-versa. I know the gague worked before, but it couldn't hurt to check.