Calling for a Pow wow from the Best and the Brightest - Overheating.

[commando1]

OK, this is some serious **** and I'm about to throw a stick of Dynamite under the NYB.

This one has me stumped.

No problem with cooling system in the 440 before doing the heads.
Did the heads.
Immediately overheats off the scale.

New radiator, water pump, premium thermostat. Totally flushed - no air in system.

The head gaskets were installed correctly. I'm 99% sure of it. Nothing is absolute, though.

WTF went wrong? I am totally out of solutions.
In problem solving, what changed? New Heads. Nothing else. Ergo, gotta be the head job. All other variables have been attended to.
What have I missed???

Bail me out with something simple that I am just not thinking of.

 

[detmatt]

First off are you absolutely sure it's overheating? Do you have one of those fancy thermal imaging doohickeys? Don't be mad at me for asking.

 

[moparnutcase]

Water passages blocked?

 

[Big_John]

Does the coolant overflow?

I'm wondering if you have a bad head gasket. I had the same type of issue. The car would overheat like crazy and spew coolant out like Niagara Falls. This could have finished off your radiator.

I would try a leakdown test on each cylinder and I'll bet you have an issue with the head gasket sealing. It might be an idea to take the rad cap off during the test and see (or hear) if there is air escaping into the cooling system.

I think this is where you need to start, regardless of what the problem ends up being... Make sure things are working correctly.

What type of gaskets did you use?

 

[tdenkler]

Water passages blocked?

Thats what I thought. I have bad habit of not matching water holes in head gasket to head itself! Twice!

 

[bulldogchesty]

I used one of those " premium " thermostats in my mothers old Dodge, and it overheated all the time. I change back to stock and it worked out fine.

 

[Stormer]

You don't need a thermostat in FLA, yank that ***** out & see how she runs. But, you probably blocked a passage with the head gasket.

 

[bulldogchesty]

I would beg to differ. The coolant would be flowing so fast through the block, the radiator won't have time to cool anything.

 

[commando1]

First off are you absolutely sure it's overheating? Do you have one of those fancy thermal imaging doohickeys? Don't be mad at me for asking.

No IR reader.
I'm absolutely sure, Matt.
It can idle all day and it stays at 2/3rds. scale. Gt it out on the road, it pegs. Bring it back down and let it idle, it goes back to 2/3rds and stays there. Zero air in system. You can watch the flow with the cap off.

 

[commando1]

Water passages blocked?

When the heads were done, the water passages were clean.

I wish I had paid more attention to the gasket. I very stupidly did not check if the holes for the water passages lined up. I took it for granted and now i don't know. My bad on that one.

 

[detmatt]

Are you collapsing a hose?

 

[commando1]

What type of gaskets did you use?

To answer your question, I went back to the summit site to give you the link to the gaskets I used.

That's when I noticed this:

Notes:
​

Installation of these copper head gaskets requires O-rings.

Excuse me B&B. Thank you all for your help.
It's 5:00 Happy Hour and tonight I am not stopping at two beers.
I'm getting drunk.

 

[Ironwolf]

Any white smoke spewing from you exhaust ?

 

[detmatt]

O rings sold seperatly?

 

[Big_John]

O rings sold seperatly?

You would have to cut a circular groove around each bore in the deck of the block for the O rings. I'd say that's not something you can do with the short block together and in the car.... and usually only done in high cylinder pressure (supercharged, big NOS shot etc.) applications.

 

[Pete Kaczmarski]

Was the heads redone for any reason other than overheating? Was something else done like the camshaft?

 

[70bigblockdodge]

I hate to ask this and I hope you tell me yes, don't ask dumb questions. But is there a baffle in the top tank of radiator since both your hoses are on the same side? If you put head gaskets on wrong it would really just heat up rear of engine as stepped holes to force water toward rear of block and up into head, I don't see it overheating just not heating evenly.






Re read so its the head gaskets?

 

[1978 NYB]

I would take another look in the radiator to see if it is still full after cooling off overnight. I had that overheating problem twice last year when the water pump started leaking and then again after that North Korean thermostat housing started pissing coolant all over the place. The same overheating scenario happened to me. It was air trapped and I drove it for an hour and let it cool down overnight and filled her up the next morning. I did that 2 or 3 times and she went right back to the old faithful spot the gauge.....even at 114 degrees at Carlisle.

 

[oldtinkerer]

bad water pump impeller loose on shaft cools at idle won`t cool at higher rpm

 

[polara66hardtop]

Maybe wrong gaskets? My 74' 440 has slots in the head for more water, the old (72 and older) head gaskets don't accomadate that.
Just a thought.