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Topic: '88 Sport still running warm..... (Read 2147 times) previous topic - next topic

'88 Sport still running warm.....

My '88 5.0L Sport is still running warm....I broiled out the rad w/ a vinegar mix and changed the thermostat. 

When rolling along it will run ok on the temp gauge then the needle will go right up against the top of the normal bracket for a little while then drop back down to the middle.  Last week it ran at the top long enough that the front tranny seal started leaking.  It did not help that the wife was racing a punk and gave the 'bird a flogging!  When it sat and cooled back down the seal stopped leaking.

So...the rad was flushed and thermostat was changed and the problem still exists.  What to do next??
1988 T-Bird Sport Coupe--5.0 HO, MAF swap, 1-5/8" shorties, BBK/Flowmaster exhaust, Explorer intake, 70mm Edelbrock TB, T5, B&M short throw, Centerforce clutch and PP, disc brake TC rear w/ 3.55's, TC front brakes, '98 Cobra springs, DIY SFC's, other misc .  14.05 @ 98mph with launching too low and shifting too high.

'88 Sport still running warm.....

Reply #1 –
Is the fan and fan clutch in good shape (assuming stock stuff here)?  Maybe there is air in the cooling system somewhere?

Darren

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp
 

'88 Sport still running warm.....

Reply #2 –
Are you sure it's not the gauge?  When the temp gauge pops up, do the fuel and oil pressure gauges also increase?

'88 Sport still running warm.....

Reply #3 –
Quote from: joefriday;319262
are you sure it's not the gauge?  When the temp gauge pops up, do the fuel and oil pressure gauges also increase?


+1
...and there was light!

'88 Sport still running warm.....

Reply #4 –
Maybe a bad sending unit or broken wire?

Darren

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp

'88 Sport still running warm.....

Reply #5 –
The gauges do not move together...been watching them close.  The fan appears to be in goood shape.
1988 T-Bird Sport Coupe--5.0 HO, MAF swap, 1-5/8" shorties, BBK/Flowmaster exhaust, Explorer intake, 70mm Edelbrock TB, T5, B&M short throw, Centerforce clutch and PP, disc brake TC rear w/ 3.55's, TC front brakes, '98 Cobra springs, DIY SFC's, other misc .  14.05 @ 98mph with launching too low and shifting too high.

'88 Sport still running warm.....

Reply #6 –
Quote from: aerocoupe;319246
  maybe there is air in the cooling system somewhere?

Darren


+1
41 Dodge Luxury Liner Sedan
78 F-100 2wd flareside
84Turbo Coupe
84 Thunderbird Élan
85 Thunderbird 3.8
88 Turbo Coupe
88 Mustang GT
90 Stang LX 5.0 5spd
93 F-150 4x4 ext cab
96 Mustang GT
98 Mustang GT
99 SVT Cobra
06 Fusion SEL
14 Fusion Sport

'88 Sport still running warm.....

Reply #7 –
......and how would I get the pocket of air out?
1988 T-Bird Sport Coupe--5.0 HO, MAF swap, 1-5/8" shorties, BBK/Flowmaster exhaust, Explorer intake, 70mm Edelbrock TB, T5, B&M short throw, Centerforce clutch and PP, disc brake TC rear w/ 3.55's, TC front brakes, '98 Cobra springs, DIY SFC's, other misc .  14.05 @ 98mph with launching too low and shifting too high.

'88 Sport still running warm.....

Reply #8 –
One trick is to drill an 1/8" hole at the top of the thermostat in the lip.  This allow it to burp past the thermostat but not flood past during normal operating conditions so the thermostat actually works.  I drill it and then do this to hold it in the 12 o'clock position:

 

Darren

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp

'88 Sport still running warm.....

Reply #9 –
Or just leave the cap off and run it till it burps off, Your thermostat seems to be working, it  raises the temp and when it opens the temp drops. If your rad. is in poor shape it may still be clogged. If you know for sure your fans working. and it heats up at a sit still It probably is your rad. It wouldn't be by chance it's full of debris in the front of it between the ac condenser and the rad?
Old Grey Cat to this.88 Cat, 5.0 HO, CW mounts, mass air, CI custom cam, afr165's, Tmoss worked cobra intake, BBK shorty's,off road h pipe, magnaflow ex. T-5,spec stage 2 clutch, 8.8 373 TC trac loc, che ajustables with bullits on the rear. 11" brakes up front. +

'88 Sport still running warm.....

Reply #10 –
I reread the original post and I think you are on to something Kitz Kat.  I read the boiling out part but what about the radiator getting rodded (mechanically cleaned)? 

Darren

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp

'88 Sport still running warm.....

Reply #11 –
For the price, you can get a new stock one for less than 100.
Old Grey Cat to this.88 Cat, 5.0 HO, CW mounts, mass air, CI custom cam, afr165's, Tmoss worked cobra intake, BBK shorty's,off road h pipe, magnaflow ex. T-5,spec stage 2 clutch, 8.8 373 TC trac loc, che ajustables with bullits on the rear. 11" brakes up front. +

'88 Sport still running warm.....

Reply #12 –
You can narrow it down by the way the symptoms appear. Does the car run hot at highway speed but fine around town? That would be a rad issue. Is it hot in town but fine on the highway? That's a symptom of a slipping fan clutch.

Also, do you have a TC nose on the car? If so, the black plastic chin spoiler is a MUST. Even without the TC snoot you should have the black plastic piece there. These cars are bottom feeders (most of the cooling air comes in from under the bumper).
2015 Mustang GT Premium - 5.0, 6-speed, Guard Green - too much awesome for one car

1988 5.0 Thunderbird :birdsmily: SOLD SEPT 11 2010: TC front clip/hood ♣ Body & paint completed Oct 2007 ♣ 3.55 TC rear end and front brakes ♣ TC interior ♣ CHE rear control arms (adjustable lowers) ♣ 2001 Bullitt springs ♣ Energy suspension poly busings ♣ Kenne Brown subframe connectors ♣ CWE engine mounts ♣ Thundercat sequential turn signals ♣ Explorer overhead console (temp/compass display) ♣ 2.25" off-road dual exhaust ♣ T-5 transmission swap completed Jan 2009 ♣

'88 Sport still running warm.....

Reply #13 –
It will run hot randomly at both highway and city speeds.

Nothing is packed up between the A/C condenser and radiator.

When I filled it up with water/antifreeze, I did leave the cap off until it reached temp and it bubbled out air then topped off.

It has the factory sport nose and chin spoiler in place.
1988 T-Bird Sport Coupe--5.0 HO, MAF swap, 1-5/8" shorties, BBK/Flowmaster exhaust, Explorer intake, 70mm Edelbrock TB, T5, B&M short throw, Centerforce clutch and PP, disc brake TC rear w/ 3.55's, TC front brakes, '98 Cobra springs, DIY SFC's, other misc .  14.05 @ 98mph with launching too low and shifting too high.

'88 Sport still running warm.....

Reply #14 –
Sounds like you did it right to me.  I had one motor that just did not want to burp the air and it took several attempts.  I think I finally removed the temp sending unit and it made a small mess but that finally got it fixed.  I think the hole in the thermostat would have done the same thing but I was young and had to battle stuff back then.

I know pulling the radiator is a pain but most good shops will test it for you and give you a quote on what it would cost to rod it.  If its a factory piece then I am with Kitz Kat on you would save yourself a ton of hassle by buying a new one and just swapping them out.  I got my 3 core for both my cars cheaper online than at the parts stores here:

http://www.npdcool.com/radiator/index.php/cPath/21_396

Hope you get it figured out as this problem is right up there with diagnosing fuel/ignition issues.

Darren

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp