[longeuayms]

Hey everyone.

I've been battling an overheating issue ever since I put the engine back in to my 65 convertible. Originally my mustang didn't drive (I bought it that way), I got the engine to fire up and run for a few minutes to make sure it would run. Then I pulled it, detailed the engine bay and put it back in.

Since then I have had a huge overheating problem...it will overheat in a matter of minutes!

Here is what I have done to the engine so far.

Replaced all the hoses,
Ran the hose through all the water outlets/inlets.(the water flowed freely so there isn't a major block anywhere).
added Edlebrock Intake and 650cfm Edlebrock carb
New fuel lines,

--- I got it running, and it was running hot.

Then I replaced: (all brand new items)
Radiator (3 row aluminum) and added a 13lb cap, thermostat (put in the correct way), waterpump, and a radiator fluid overflow tank.

---It continued to overheat.

Today I installed an electric radiator fan (the pull air through type),

---It is still overheating.

It will pit out fluid via the overflow tube to the over flow tank, then it will fill up the tank and out onto the street (or into my catch basin in my driveway).

I have ran it with the radiator cap off, and at idle it doesn't look like the radiator fluid is flowing, but it does when you idle up a bit.

I need some real help here, I can't figure out why it is still overheating, and why it is overheating so quickly. I have owned 6 mustangs (65s and 66s), none of them overheated as bad as this one does.

Could this be a crack in the block? Head problem? A clog somewhere?

Thank you in advance for your input, I love this community!

Sincerely,

Mustang Mike.

[dakine858]

My best guess is that you have a blown head gasket.

[yellowtonka2]

when it is running is it missing pretty bad or at all and did you pull any of the spark plugs to see if they are washed if the head is cracked or the gasket blown alot of the time you will find a spark plug that looks like it is brand new while the rest will be brown or black. the antifreeze will clean it good indication of a head o5r head gasket

[longeuayms]

It does not miss or run rough at idle, it sounds great other then a small ticking noise. I will check the spark plugs and get back to you. I put brand new spark plugs in when I dropped the engine in a month ago.

What other indicators would I see if it was a blown head gasket? Would a blown headgasket cause it to overheat that rapidly?

Thanks again. I'm sure we'll have this pinned down in no time.

-Mike

[dakine858]

Originally Posted by longeuayms

It does not miss or run rough at idle, it sounds great other then a small ticking noise. I will check the spark plugs and get back to you. I put brand new spark plugs in when I dropped the engine in a month ago.

What other indicators would I see if it was a blown head gasket? Would a blown headgasket cause it to overheat that rapidly?

Thanks again. I'm sure we'll have this pinned down in no time.

-Mike

Yes a blown head gasket will cause your engine to overheat with the quickness.

What mix of coolant/water are you running? What's your ignition timing at? Is your radiator cap in good condition? Have you noticed any coolant loss? Do you have A/C in your Mustang?

Some more possibilities are;
-a cracked or leaking freeze plug(s)
-incorrectly adjusted (tensioned) drive belt
-improper ignition timing
-airflow restriction in front of the radiator (dirty A/C condenser or plastic bag stuck on the front blocking airflow *happened to me*)
-improper fan installation (reverse-rotation fan installed by accident, or fan installed backwards)
-improper valve timing (cam sprocket installed improperly)
-coolant in the engine oil.

Plus, if your radiator cap isn't rated for the proper PSI, the coolant will boil at a lower temp. For example, water boils at 212 degrees with 0 pressure, at 4psi it boils at 224, at 7psi it boils at 232 etc. So if your cooling system can't properly pressurize, you'll easily overheat.

[Jay H 237]

I take it you don't know the previous history of this motor and what's been done to it in the past?

Two more things to add to the list of possible problems,

someone replaced the head gaskets and have them on backwards so some of the coolant passages are blocked.

defective waterpump (impeller?)

[yellowtonka2]

you said you had the rad cap off and it didnt look to be ciculating probably not a head gasket if it were you d prob see the coolant bubbling from compression getting into the water jacket

[longeuayms]

Thanks for the input guys. I'm at the fire station tonight, but I'll be able to work on my mustang when I get off in the morning.

To answer some of your questions for me:
I'm running 50/50 coolant to water
I'm not sure about the timing (I will check it tomorrow).
Radiator cap is in new condition (13lbs)
The only coolant loss I've noticed is from it coming out the overflow tube.
There is some moisture coming from the exhaust on both sides when I start up my mustang and shortly thereafter.
I do not have an AC system.
There is nothing infront of the radiator to block the flow and I added an electric fan and it pulls air through (i tested it by dropping a bag in front of the radiator and it sucked it up against the fins).

I do not know the history of the motor and neither did the previous owner.

How can I check if the headgaskets are on correctly??

Thanks again.

-Mike

[dakine858]

Originally Posted by longeuayms

Thanks for the input guys. I'm at the fire station tonight, but I'll be able to work on my mustang when I get off in the morning.

To answer some of your questions for me:
I'm running 50/50 coolant to water
I'm not sure about the timing (I will check it tomorrow).
Radiator cap is in new condition (13lbs)
The only coolant loss I've noticed is from it coming out the overflow tube.
There is some moisture coming from the exhaust on both sides when I start up my mustang and shortly thereafter.
I do not have an AC system.
There is nothing infront of the radiator to block the flow and I added an electric fan and it pulls air through (i tested it by dropping a bag in front of the radiator and it sucked it up against the fins).

I do not know the history of the motor and neither did the previous owner.

How can I check if the headgaskets are on correctly??

Thanks again.

-Mike

The only way to check if the headgaskets are on correctly is to remove the cylinder heads, at which time you'd be putting new ones on anyway. It's a very bad idea to pull engine heads that have been bolted down for a number of years and put them right back on without replacing the gasket, it's asking for trouble.

Next time you get a chance try this; Jack the front of your car up (high enough so that you can get to the oil pan drain plug. Next, run your engine up to operating temperature (so the thermostat opens) and let it idle for 5 min. Now shutoff the engine and immediately slide under your Mustang with a clear plastic container that you can drain a little bit of oil into. Unscrew the oil pan drain plug and let about a cup of oil pour into your container. Re-tighten the drain plug and get up to have a look at your oil sample. If the oil is a milky/creamy brown color and or really runny/watery, then you'll know right away that you have a head gasket leak. Start with that and see what you can find out then post up the results and we'll go from there.

[The Greek]

I'm willing to put money on the headgaskets being installed wrong. Inexperienced people will want to install both gaskets so that they look the same on both sides. One will look upside down when installed correctly.

I'd go ahead and bite the bullet and go with pulling the heads before letting the engine overheat again. You don't want to damage the engine. Everytime it overheats you have a good chance or warping heads, cracking heads or block and bearing damage.

[longeuayms]

Thanks for all the help. I took it to my mechanic and he said it's most likely a blocked passage in the block. The engine came from an east coast stang, so I'm just going to take it out and replace it with a southern california 289 or 302. I'll keep you guys/gals posted as I go along.

Thanks again.

-Mike

[The Greek]

Mike, did they build them in a different way in SoCal? Is it that people are smarter there?

[longeuayms]

Originally Posted by The Greek

Mike, did they build them in a different way in SoCal? Is it that people are smarter there?

Greek,
It has nothing to do with the people, but rather what the environment does to the vehicles/engines. The engine coolant passages in my mustang were blocked by rust-debris, there is a greater chance of that not happening with a mustang that was born and raised in socal.

It also turns out that along with those passages being blocked the head gasket was blown.

My mustang is running great now. Next up it's paint/new top and then putting everything back togther.