PDA

View Full Version : Engine Cooling Questions



Ross
04-24-2007, 07:24 AM
OK, so I have had my new engine for about 2,500 miles. Of course, the reason I had to get it was because of extreme overheating which fried my old engine, so I am now very gun shy about any fluctuations in engine temperature.

Historically, when my MM has been up to operating temp, the needle points to about the 18 MPH mark on the speedometer. Roughly 45% up the temp scale. (It would be easier to describe if our temp gauges had numbers or marks.) No matter how far I would drive, and no matter what the outside temp was, the engine temp was rock steady at 45% up the gauge.

Since I have gotten my new engine in, I made one trip about a month ago which was almost 100 miles each way. On the way back, the temp gauge went up to about 65% up the gauge. Not enough to pull over and shut off the engine, but enough to get my attention and get me concerned. I talked to the dealer and they confirmed that when the new engine was put in, they used new coolant, a new fan motor, and a new thermostat. They checked the thermostat, however, and said that it wasn't opening completely, so they replaced it. NOTE: I kind of wondered if this was a correct diagnosis, since the slightly higher temp didn't show up on the first trip away from home, and didn't show up until I had driven at least 50 miles on the return trip. It seems like a thermostat that isn't opening all the way would have caused higher temps sooner than that.

Anyway, the higher temp showed up again a few days later, after not much driving, so I decided to "burp" the cooling system and let out any trapped air. Sure enough, there was air in the system, so I let it out and filled the system with coolant through the top filler hole. NOW, I'm hoping that the problem is fixed, but I'm keeping an eye on things anyway.

A few weeks later, I take a trip which is about 200 miles each way. On the way over, outside temp about 80 degrees, the gauge once again gets up to about 65%, and fluctuates slightly back down to almost normal, then back up again.

On the way home, no fluctuation, and the gauge shows a normal 45%, but the outside temp is only about 65 degrees.

I'm really concerned now. What is going to happen the first time I need to make a long trip when the outside temp is in the 90's? That will be soon down here.

The dealer says that I maybe need a radiator flush. Maybe, but if that's it, why doesn't the temp get higher sooner? It isn't getting higher than normal until after a long highway drive. Anything in the system (Thermostat, radiator, fan, etc.) should cause problems sooner than that, shouldn't they?
With a brand new engine, I really need to make sure that my cooling system is up to par.

Anyone got any suggestions?

KillJoy
04-24-2007, 07:28 AM
I do not think this would have ANY effect on your situation, but.... did you have the Rear Head Cooling Mod done w/ the Engine Swap?

KillJoy

Zack
04-24-2007, 07:36 AM
Sounds like there is still air in the system.
Ask your dealer if they installed the coolant with the Ford tool called the Mighty Vac. If not, find a dealer that has one.

Also, take the plastic cover pieces off the top of the radiator, and you will probably see years worth of road dirt and cotton. It is the side of the radiator that the condenser blocks, so you cant see it.
Ill bet you find its almost completely blocked.

RF Overlord
04-24-2007, 07:42 AM
Maybe you still have some air in the system...try burping it again?

Another thought...perhaps there's some detritus stuck between the radiator and the A/C condenser that's reducing air flow. Leaves...pine needles......a Civic...

Dammit...Zack beat me to it while I was typing...why isn't he at work?! :lol:

Ross
04-24-2007, 09:42 AM
No cooling mods. I guess this weekend I'll tear apart the plastic cover and give everything a good hose down to clean it all out.
The thing that scares me is that it's only been getting hotter on a long trip, so there's no way I can tell whether the problem has gone away until I'm far from home, maybe on a lonely highway somewhere.:alone:

magindat
04-24-2007, 10:31 AM
No cooling mods. I guess this weekend I'll tear apart the plastic cover and give everything a good hose down to clean it all out.
The thing that scares me is that it's only been getting hotter on a long trip, so there's no way I can tell whether the problem has gone away until I'm far from home, maybe on a lonely highway somewhere.:alone:

RF started to mention a Civic. Couple of things when I had similar probs in my ricer days....

1) To rule out sticky thermo, run without one if temps permit (not cold).

2) There could be junk in front of the rad, behind the condenser.

3) There could be 'flat fins' in the front of the rad for the same reasons.

4) Make sure your plastic air dam in properly in place below the rad.

5) Wouldn't hurt to flush and or BACKFLUSH the rad/system to be sure there's no FODs in the system.

In my case, running w/o thermo worked and a BACKFLUSH revealed FOD in the system. No idea what it was or how it got there.

Local Boy
04-24-2007, 11:01 AM
Here's the obvious, What is the temp. setting for the thermostat? As you know - too high a setting opens (Thermo.) late, causing engine temps. to rise. Once open, engine temps. drop... Temp. drop causes the thermo. to close, and the engine temps. rise again (Fluctuates).
On a totally different point of view, perhaps the electrical parts responsible for calibrating air/fuel ratio is dirty or malfunctioning causing a "lean" condition which results in heating issues. When its hot is there idle surge, or higher RPM's at idle? This would point to a "lean" condition.

BLACKMARAUDER04
04-24-2007, 12:08 PM
Possibly a bad sender unit?

pez
04-25-2007, 02:47 PM
If there was air in the system the first time, and this seems to happen less now after burping, perhaps there's still air?

vegasloner
04-25-2007, 04:48 PM
I had several issues with the my 03 late last year and into the early part of this year. Started out about the same, temp would be at that 45% mark all the time, then started noticing that in August last year it would randomly climb into the 65 - 70% range, worried me enough to pull over every time, being Vegas in August 110 is a common degree:mad2: . Shut the car off, let it sit for a couple then turn her over, temp gauge would settle at the 45% mark and all is good. Couple days later it happened again, ok, enough, bought a new thermostat and seal and swapped it out, bleed the system and now the gauage went to max. Found out a bad thermostat, replaced again, bleed system and all was good until about Janurary this year. Started to rise again, about once a week. The car is a daily driver, so I was concerned.

I went in for an oil change and heard slight winding noise under the hood:confused: . Took it to Mercury, BAD water pump. $425 later, and now 350 miles after the change, and the temp gauge is rock steady at the 45% mark.

Long story short, could of been just air in the system, but ultimatley replaced the waterpump and had the entier system flushed and filled and now it is ok.:D

sailsmen
04-25-2007, 07:59 PM
The temp guage does not move until the temp goes up 60*.

Thats why it is usually "rock solid" :shake:

As far as I am concerned it is an idiot lite.:lol:

Zack
04-26-2007, 05:22 AM
i did some research on the gauge and found it starts to move at 210 degrees.