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67 mustang over heating

This car has me stumped I’ve got a 67 mustang that is overheating only while driving I’ve replaced the radiator new 180 thermostat facing the proper way bypassed the heater core replaced the head gasket flushed the cooling system but after running vehicle for ten to fiften minutes one side of the block is reading 178 drgrees the other side is reading 240 in lost

Who overhauled the engine? It’s possible that someone installed an incorrect gasket or installed a proper gasket incorrectly.

Which engine?

I thought that too also forgot that it’s on its third water pump I did the engine overhaul only the top end pulled that side and replaced the gasket to double check

289 also forgot to mention it’s on its third water pump

Make sure you’re getting the correct water pump. There are ‘standard’ and ‘reverse rotation’ pumps for 289/302 Fords, it seems:

Is there a way to tell which one it’s supposed to have

I’m thinking I might have to pull the motor to pull the freeze plugs and check to see if the water passages are blocked

How are you measuring the temperature and at what location on the block are you measuring? And as for 3 water pumps, what was the problem with the pumps?

And fwiw I recall a Ford engine years ago that had a peculiar overheating problem that seemed to defy all logic until I overhauled the engine and found a sand hole casting imperfection in one cylinder that allowed compression to escape into the water jacket.

Pulling the motor seems a bit extreme at this point. I’m thinking along the lines of a wrong water pump as mentioned by texases or an incorrect head gasket as mentioned by Rod Knox.

I vaguely remember there being a difference in some of the head gaskets involving a coolant crossover port so maybe that’s the issue?

As for the water pump, short of removal you might look it over for casting numbers and compare that to the correct application.
I had a parts store hand me a 302 pump once but I caught it at the counter as I was aware of the standard/reverse rotation thing. The standards use a V-belt and the reverse rotation uses a serpentine belt.
Since the pulleys are interchangeable it can create a problem if you’re not careful.

It still has the v belt on it but the motor does turn counter clockwise would there be a difference in pumps from stock to a 289 hp this vehicle was brought to me with this problem and I’m determined to get it figured out

The pump rotation is opposite when a serpentine belt is fitted (newer 302), so you need to make sure you have a pump for the early, v-belt engines.

I’m gonna pull the pump but the parts store is only showing one pump number I’m praying on a miracle I want to assume it’s gonna be something easy I’m over looking I’ve been turning wrenches for about 15 years now and I’ve never had a problem on such a simple system I’ve pulled that head twice thinking I had the gasket messed up some how but this vehicle has had this problem for some time before it has now landed in my garage

Assume you mean “as seen from the drivers seat.”

Sure sounds like a plug in a coolant passageway in the “hot” side.

The only way I’m gonna be to find out would be to pull the freeze out plugs only one side of the block is getting hot it leads me to believe I’ve got a flow issue on that side

60’s Mustangs are a popular collector’s car so there’s lots of experts on this subject for you to consult. You can find them by looking through one of the many Classic-Mustang specialty magazines and looking through the advertisers. I’ve seen those magazines at almost all places that sell magazines. Walmart, Target, Barnes & Noble, etc. The experts in those magazines – the advertisers --will be able to definitely tell you which water pump your 'STang (editted, in deference to db’s post below) needs. By now I expect the engine has been replaced, maybe a few times, so if that’s the case you’ll need the specs on the engine actually installed, not the engine that came with it new. I expect you already know that. Parts stores by default sell you the pump for the engine as the car was configured new.

Another thing to check that’s easy to do, make sure the fan is blowing in the correct direction.

Edit: I’ve seen water pumps installed on the 302 engine without the required backing plate, and that can cause weird overheating problems.

What I think you’ll wind up doing however, after all is said and done, is removing the head(s) again, verifying no coolant paths are being covered by the head gasket b/c it is the wrong one for the engine or installed on backward (hey, it happens, and overheating is the usual result!) and flushing all the coolant paths from the top of the engine block, and making sure they all – one by one – run through as easily as all the others and out the bottom side.

AFAIK . . .

'Stang is short for Mustang

'Tang is short for something else, and since this is a family-friendly forum, I won’t say just what that is

Hint . . . it’s not the beverage that is similar to Koolaid


Did someone discard the water pump plate? It is positioned between the water pump and engine, #8508 in the image.

I’m gonna start back into the tear down today I’ll be starting with water pump and moving on to heads just to cancel out likely suspects one at a time

Just to be clear - the pump type depends on whether a v-belt or a serpentine belt is used. The engine turns just one way, regardless.