Help Me Fix This Cooling Problem!

[silvergt2001]

Well, now that I have my charging problems corrected, it's time to move on to cooling.

At idle and in town cruising I have NO cooling issues whatsoever with my stock rad/electric fan combo.

As soon as I hit the freeway cruising at speeds in excess of 60 MPH my tempgauge goes from reading 3 or 4 o'clock to 2 o'clock. WHAT GIVES??

Mods: .62 overdrive 5 speed w/4.10's, underdrive crank pulley, stock wp pulley, taurus fan (high setting), 180 tstat. Cruising at 75 I am at about 2400 rpm I believe.
What is wrong with this thing??

 

[90]

maybe your stock rad went bed.. that dont make anysence to me.. it should be fine on the freeway cuz of the wind.. and over heat in town do to lack of cold air.. if it is your rad, autozone sells a nice aluminum one thats nice.. im not using it but my buddy put one in his t/a and it works fine.. i'd put a 3core aluminum rad and keep your elc fan combo!

 

[TheBocSez]

Missing the lower air deflector which pushes air up to your radiator?

Taurus fan on at high speed all the time could cause more of an air impedance than help at highway speeds.

 

[silvergt2001]

The air deflector is the lower "lip" of the front clip, I assume? If so, yes it is on there.

Guys this is driving me nuts. I've flushed the system 3 times already. The car broke down on me the other day, overheating on the freeway and blew a hole in one the cooling tanks. I replaced it with a 4 cyl rad and a new 16lb cap.

When I flushed it originally i had to use a air hose to send pressure through the drain **** and blow the rust and grime out of the drain so the coolant could be released. It was completely clean on the last flush, especially with the new 4 cyl radiator installed. (and yes it is the same as the v8).

Once again, it rarely gets hot around town, but the gauge goes to 2'oclock on the freeway.

I replaced and checked hoses for blockages, nothing.

Thanks in advance!

 

[HISSIN50]

I'm not sure I'd have gone with a stock radiator (as opposed to an alum or HD 3 core unit) in your Texas heat.

What kind of revs are you turnin while on the freeway? Does this happen even if you just have the CC on?

Is the front of the condensor clean?

Good luck.

 

[silvergt2001]

Well, the condenser is clean and only has a couple flat spots. My speedo does not work, I'm still contending with that issue. I do know that on the freeway I "go with" traffic cruising at about 22-2400 rpm.


*edit*......the three core is coming thursday, but I'll have to re-work the taurus shroud for clearance. I put in the stock rad because of $ shortages. Thank you for the reply.

 

[trents99]

Do you still have an overflow tank?

What is your procedure for refilling the cooling system?

 

[RYC CUKR]

I had the same type of issues with my 88 and the stock radiator.

In town temp was fine but on the highway it would slowly heat up. Never overheated but got a low hotter than I was comfortable with.

Put a new 2 core aluminum in and it sits right on 180 all the time.

Also the air deflector is a black piece of plastic that is fastened to the underside of the radiator crossmember.

 

[silvergt2001]

Ok I checked on the air deflector and it does appear to be missing.

The overflow tank was removed also when e-fan was installed.

Being that I am losing a little coolant while driving with no apparent drips I took a closer inspection. With a laser-heat tester device I checked everything at normal operating temperature.....All my headers were reading I believe 310 or so except for my #1 cylinder which was reading nearly 80 degrees less!! So it's my belief that I have a partially blown head gasket superheating my coolant at sustained higher rpm's. Just wait to laugh at me after I do it and still have the same problem, lol.

I'm walking outside right now to put on a passenger-side headgasket, and I'll keep everyone posted throughout the day. Once again thanks for all the help and replies everyone.:SNSign:

 

[$uperstang]

Sure sounds like a head gasket

 

[Killer50stang]

Sounds like a fan problem. How much CFM's are you pushing? What timing are you running? Stock gauges sucks, get an autometer if you don't already.

 

[silvergt2001]

Well guys, I attempted to start the job several times but it stormed all day.

Killer50, I too thought it was a fan problem at first, but I was told by two friend/mechanics that the fan I'm using on the high setting is pulling more air throughout most rpm's as the the stock clutch/fan assembly. The thing is, at idle I have NO cooling issues or even cruising through town. The problem only occurs at sustained cruising above 2,000 rpm's, when simple airflow through the rad should cool the car. I guess I really need to do a combustion chemical test of the coolant.

Well guys I'm gonna park it for a couple days because the problem seems to be getting worse, and I don't really have the time to pull the head right now. I'll keep this updated, and thanks again to everyone.