93 Tbird 5.0 HO overheats with A/C on

Topic: 93 Tbird 5.0 HO overheats with A/C on (Read 3471 times) previous topic - next topic

93 Tbird 5.0 HO overheats with A/C on

May 11, 2013, 03:45:50 AM

Car runs perfectly cool as long as you do not turn on the A/C.

It runs at just before the N of NORM on the temp gauge when I have the A/C off, if I turn on the A/C, the temp rises and rises until I turn it off, then goes back to its normal area.

I just changed the thermostat because I think this problem was T-Stat related. overflow was empty earlier from leaking out because i didn't torque the bolts to their specs, but I have fixed that now, and refilled the overflow bottle.

When the Fan clutch engages, is the wind noise under the hood suppose to be loud like on the 80's v8s, or is it generally quiet. Because I see the fan moving, and when I hear it engage, the noise never gets louder.

I may have a bad fan clutch, because under normal driving conditions, it doesn't need to engage the fan, but with the AC on it probably needs it, and cant engage cause of bad clutch.. So what do you guys think it is?

93 Tbird 5.0 HO overheats with A/C on

Reply #1 – May 11, 2013, 09:25:17 AM

What is the condition of the radiator? I could be old and plugged up and not cooling properly when the extra heat is pulled through it with the ac on.

I dont know much about the 93's, is the fan electric or mechanical?

93 Tbird 5.0 HO overheats with A/C on

Reply #2 – May 11, 2013, 02:48:41 PM

Quote from: mcb82gt;414902

What is the condition of the radiator? I could be old and plugged up and not cooling properly when the extra heat is pulled through it with the ac on.

I had that issue on my Thunderbird last summer. 95*-100* heat plus A/C on the highway resulted in the temp gauge going to the top of the scale. Not overheating but going right to the top. The 25 year old radiator finally had plugged up enough to cause the problem with the A/C on. If I shut the A/C off the temp went back down. I replaced the radiator and all was well.

Does the car get hot/overheat all the time with the A/C on, only in stop and go traffic/idle, or at high speed on the highway? If it's one of the first two the fan clutch is probably on it's way out. If it's the last one the radiator is probably plugged up.

A new radiator or fan clutch shouldn't cost you more than $100.

93 Tbird 5.0 HO overheats with A/C on

Reply #3 – May 11, 2013, 11:23:57 PM

Quote from: mcb82gt;414902

What is the condition of the radiator? I could be old and plugged up and not cooling properly when the extra heat is pulled through it with the ac on.

I dont know much about the 93's, is the fan electric or mechanical?

The fan is mechanical, and the radiator looks good on the outside, looks new to me, but that could just be cause of the low miles of the car..

93 Tbird 5.0 HO overheats with A/C on

Reply #4 – May 11, 2013, 11:26:32 PM

Quote from: thunderjet302;414918

Does the car get hot/overheat all the time with the A/C on, only in stop and go traffic/idle, or at high speed on the highway? If it's one of the first two the fan clutch is probably on it's way out. If it's the last one the radiator is probably plugged up.

All the time with the A/C on, and in stop n go, I haven't tried high speed on the highway yet, been cool enough to not use the A/C, but gotta fix it fast before California summer hits me.

93 Tbird 5.0 HO overheats with A/C on

Reply #5 – May 12, 2013, 09:56:47 AM

Make sure the belt is in good shape and not slipping on the fan pulley. A fan clutch is about $50 so try that first as it cannot hurt with the age of the car. The radiator most likely has plastic ends so having it serviced is most likely out of the question. You can find new ones for about $90 and up so that's not too bad either.

Darren

93 Tbird 5.0 HO overheats with A/C on

Reply #6 – May 12, 2013, 10:20:28 AM

with a bone cold motor,
you should not be able to grab the fan and spin it more than a 1/4 turn with all your might. Ill give you a 1/4 turn but if it goes more , lets say you can spin it like 1/2 turn then replace the clutch. cheapest fix and actually it would be a preventative maint step. car has low miles so it should not be junk by now but you never know.

93 Tbird 5.0 HO overheats with A/C on

Reply #7 – May 13, 2013, 05:24:04 PM

Well today, I found a split hose from the water pump to thermostat housing, shooting coolant all over my intake..

ordering it right now

93 Tbird 5.0 HO overheats with A/C on

Reply #8 – May 14, 2013, 06:52:35 AM

Put an external tranny cooler on that AODE transmission!!

93 Tbird 5.0 HO overheats with A/C on

Reply #9 – May 14, 2013, 07:58:19 AM

was thinking about that actually :)

93 Tbird 5.0 HO overheats with A/C on

Reply #10 – May 14, 2013, 07:59:12 AM

the trans does get a little warm in the cab of the car, you can feel it thru the center console. although cooling the fluid might not fix that all that much..

93 Tbird 5.0 HO overheats with A/C on

Reply #11 – May 14, 2013, 09:03:31 PM

Is there a specific trans cooler you guys buy that's offers a direct fit adapter, so there's no line cutting involved?

93 Tbird 5.0 HO overheats with A/C on

Reply #12 – May 14, 2013, 10:40:49 PM

Well, I know on my foxbody, I spliced it inline and used the supplied barb and hose to plumb it in.

93 Tbird 5.0 HO overheats with A/C on

Reply #13 – May 15, 2013, 12:11:59 AM

Quote from: beast50;415105

Put an external tranny cooler on that AODE transmission!!

Actually the MN-12s through 93 use the regular AOD. 94-97 MN-12s use a 4R70W.

As for a trans cooler just use the biggest one you can fit.