OK here is the story: Maybe 2 months ago I bought a ’88 Trans Am GTA with the 350 TPI motor. While I have owned her two things have been apparent, but not seemed to be an urgent problem.

1 The heater blows cold
2 There is a slight coolant loss.

OK, so I use the car once or twice a week. I top up the coolant and think “I best fix all this before it gets cold”. I look for obvious signs of leaks but find none. (When I first bought the car there was a rust stain on the expansion tank like the car had boiled over through there in the past. I forgot to ask the vendor about this at the time.)


So I sell my old daily driver and buy a V6 Mustang and of course the first thing that happens is the ignition dies on that so I have to daily drive the Trans Am while I wait for the parts to fix the Ford. This is the Trans Am’s cue to remind me that any fault like coolant loss should be properly investigated as soon as you spot it...

In city driving the car gets hot (the gauge is the digital type, it reads just below the red and maybe drops a point or so below this, I appreciate the gauge won’t be really accurate 25 years old). I guess its reading 230-240 or so. Before this it read about 220 in the city and 200 on the highway. I understand this is normal.

When I stop I see steam. It rises up through the “nostrils” in the hood. When I stop the car and pop the hood I can see steam rising from somewhere in the region of the crank pulley. It’s impossible for me to tell right now if it’s coming from the rad, the hoses, the water pump... When I previously looked there was no sign of a leak here. But I wasn’t getting it steaming out before.

When I turn off the motor I can hear the coolant gurgling.

The SES light does not come on.

So.

My plan of action is this:

Firstly I post on here and ask if anyone knows is there any “weak point” in the cooling system which I should know about. I don’t know these cars, it’s my first one and I have not had it long.

I will refill the coolant system again. I am using tap water and about 20% antifreeze.

I will check again for any signs of leaks, damage to the lower hose, rad, couplings, etc.

Remove thermostat to check it’s not jammed.

Check for leaves, junk etc blocking the radiator and thoroughly clean the thing as best I can.

Check for any error codes off the OBD

I will start the motor from cold with the radiator cap off and see if there is any bubbling coming through to indicate head gasket failure.

Turn the heat on and reverse flush the cooling system. Check the heater control valve is opening.

Replace cap and let it rise to normal temperature. Check for obvious leaks or damage if I can still see steam.

Any other thoughts or tips and tricks for diagnosis?

Thanks in advance.

I am over in England and parts and expertise for these cars is not so easy to find here.

 

Pressure test the cooling system and check the weep hole on the water pump.

 

thanks. I'm not entirely sure what a week hole is and what it might mean if its, well, weeping? Is this a pump fault?

 

It's a hole drilled in the body of the pump so you can see coolant dripping out when the shaft seal is starting to wear, before it fails completely.

 

Thanks, makes sense I'll see what I can see.

 

X2 on the water pump, Error codes will not help you to pinpoint a coolant leak.

 

what you need to do is verify that your radiator cooling fan is operational, now since you say you're up to the red, this leads me to believe that either your radiator is plugged and time for either a cleaning or a replacement, the other obvious would be the radiator fan motor is either shot or not getting grounded by the temp fan switch, you either need to confirm it's the fan that is shot or the switch... now as for no hot air blowing check the passenger floor for any signs of coolant... also make sure that you actually have heater lines connected to the heater core...

 

Thanks for the suggestions, I'm just taking 5 from checking it out now.

 

OK, problem was pretty self evident as soon as I filled up with coolant. Water pump has failed. I have a new one on order. Does anyone have any tips and tricks for swapping out the water pump or is it all straight forward?

 

It's about as easy as it gets.

 

thanks for all the help and suggestions so far. This is a really helpful forum. I'm guessing the lack of heat in the heater is related. First job is to get the car running right again and then see if that fixes it or if further diagnosis is required.

Is there a bleed point to get air out of the cooling system on these cars or is it just a case of careful filling etc. when I refill it again?

 

No need for a bleed valve, the radiator cap is about the highest point in the system.

 

its not for everyone, but i usually drill a tiny hole in the thermostat to help bleed the air out of the block on first start up. this will mean that you've always got a small flow of coolant through the the stat, but i never had issues with it

 

replace your radiator hoses as well as using new clamps, you also may want to swap thermostats, you could use a 180 degree thermostat, if possible get a fail safe thermostat, these should already have a hole drilled... they're typically around 12 dollars or so compared to your generic thermostats which are a few dollars... when I did my water pump on my carb engine I took the alternator and the compressor out of the way to ease things up... You most likely have a different setup so just look at your water pump and go from there... make sure you clean the block side really good either with a knife or some fine grit sand paper, you could also use a putty knife, but don't try using a chisel...

 

OK, all done except I am struggling getting the serpentine belt back on. I have a nice new belt and I can't seem to get the tensioner out of the way enough to get the belt back on properly.

Is there a trick to this?

 

Is the new belt the same length as the old one?

 

Use a 1/2" ratchet (set on loosen) in the square opening on the tensioner pulley bracket, and turn it backwards all the way to slip the belt over the final pulley.

 

I'll compare the two. It wouldn't be the first time I got sent something not-quite-right. The old belt split as I took it off. Definitely ripe for replacement! I looked at guides on YouTube etc and there doesn't seem to be anything more to it... Annoying as I could be back on the road with it now...

 

Aha! That sounds like the sort of info that should be in the workshop manual!

 

You mean it's not?

 

No problem.

Did it solve the issue?

 

The manual simply says "swing the tensioner pulley away from the belt to release tension"

I'd been messing about until the suggestion to put a ratchet in that square recess. That worked like a charm. I'm sure I warned you all I'm a newbie!

Car runs and drives great now, does not get hot, does not seem to be losing coolant any more.

I have a couple of other issues with it, I'll start a fresh thread as they are kinda unrelated.

 

Awesome, glad to help. That seems really vague for the manual to just say to "swing" it away...

Good luck with the car!