Alright, why is this thing overheating?

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Yeah, what crossram said! But usually that happens when revvin'

And uhh..whats up wit da head gasket?:read2::-D
 
:-D

CudaVert

gts-dart said:
air pockets could also indicate a combustion leak (bad head gasket, warped head, crack). but if that was the case it would overheat all the time. idle only overheating is lack of airflow.
Click to expand...


Well, how do ya figure we could check for combustion leaks into the cooling system? I'm thinkin the rad cap would be a good spot!:-D




Your - belongs to you
You're - You are
Its - Belongs to it
It's - It is
Brake - Slows your car
Break - Falls apart
There - Not here
Their - Not yours
Here - Not there
Hear - To perceive sound
Lose - To not win
Loose - Not tight
To - Where you're going
Too - It's not where you're going and it's not two, too!
RPM!!! - Revolutions Per Minute, No "'s"!!! LOL
 
Hey. Thanks for the responses.

LA Headgaskets because I wanted the skinny for added compression.
As far as I can tell, the coolant passages are all the same.

Heater core is out the loop. Those connections are all plugged.

I'm pretty sure it actually is overheating. When it got to 250, it dieseled for like 10 seconds when I shut it off.

Cap is new. I think 18 lbs.

Shroud fits very well. Its the stock setup.

I will try revving it with the cap off to see what kind of flow I get.

I don't know for a fact that it is idle only. It didn't overheat on the way to the storage (was hot though), but once I flushed the coolant to make sure I had the correct amount of antifreeze it overheated badly the next time I ran it.

I've wondered if it wasnt' something to do with the Magnum swap but I sure can't figure out what it would be.

The air Gap doesn't have a rear water crossover, but I've run other cars without that without issue.

Of course with the weather being the way it is, its hard to mess with it, but I want to be ready to go this spring.

Steve
 
You haven't addressed the fan yet.
Are you using the same fan that was on the Magnum set up? If so, the blades are pushing air instead of pulling it through the radiator.
 
The fan and all other accessories are LA stuff. The fan is the one that was in the Dart originally. I'm using V belt pullies, LA timing cover, water pump, alternator, etc.
 
How did you flush it? Do you use a lot of silicone? If it was ok prior to the flush then I'd say something is block flow somewhere. The lower hose is the outlet. I'd try draining the coolant into a clean pan, pull th elower hose off and look in it and the radiator, and pulling the top off at the water outlet and see if anything is stuck there. Did it ever not overheat or has this engine been hot since day one?
 
impeller slipping on the shaft?
do the water ports match up on "LA" and "magnum" head gaskets?
 
Keep in mind the AC and non-AC water pumps are different; AC has 6 blades, non-AC has 8. The AC cars used a different pulley set up to spin the fan faster so they put less blades in the water pump. Don't run an AC water pump with non-AC pulleys because you won't get enough flow at idle.

When the car is idling put your hand around the front of the valve cover. You should feel a pretty good amount of air coming off of the fan. If you put a piece of paper in front of the radiator at idle it should stick to the fins due to the fan pulling air through.

An infrared thermometer can really help track down cooling problems:

http://www.amazon.com/dp/B001MUV15K/?tag=joeychgo-20
 
mopar340dave said:
:-D

CudaVert




Well, how do ya figure we could check for combustion leaks into the cooling system? I'm thinkin the rad cap would be a good spot!:-D




Your - belongs to you
You're - You are
Its - Belongs to it
It's - It is
Brake - Slows your car
Break - Falls apart
There - Not here
Their - Not yours
Here - Not there
Hear - To perceive sound
Lose - To not win
Loose - Not tight
To - Where you're going
Too - It's not where you're going and it's not two, too!
RPM!!! - Revolutions Per Minute, No "'s"!!! LOL
Click to expand...

Hmmmmm.....I don't. But I was thinking that a head gasket leaking compression into the cooling system would, first of all, usually be able to unseat that 18-lb radiator cap and start pumping coolant into the surge tank.....and then air bubbles.....(I've already seen it).....OR start "pumping up" the radiator hoses with an unusual amount of pressure, early on....before the engine's really actually warmed up. That's what would tip me off......
 
............Single most reason 4 overheating is that the coolant isnt staying in the rad long enough.........put in a 195 t stat.........mopars down fall is always not enough radiator............kim............
 
8)Yeah ok, pissin contest over

I don't remember ever running more than a 14 or a 16 pound cap. Could that be the prob? A little too much pressure?
 
340sFastback said:
Keep in mind the AC and non-AC water pumps are different; AC has 6 blades, non-AC has 8. The AC cars used a different pulley set up to spin the fan faster so they put less blades in the water pump. Don't run an AC water pump with non-AC pulleys because you won't get enough flow at idle.
Click to expand...

You might be on to something. I've got a Milodon pump I *think* its their standard volume. I don't know whether the standard volume will be similar to an AC or non-ac pump. My car was AC originally. Since Chrysler uses totally different pullies for everything, and I was deleting the AC and power steering, I bought a set of pullies for a non AC/PS setup. I did notice during the setup that the water pump is actually underdriven! The water pump pulley is bigger than the crank.

So, that could be part of my problem. Might be trickier than I thought to get a set of good pullies for this.

I've got an infrared thermometer. They are awesome tools.

I've got to get a tester on the car for the head gasket leak. If I didn't have a problem originally, I might have one now that it has gotten so hot. It did seem like the pressure was very high on the hoses.

The car has always run hot, but I've never had an actual overheat before.

I didn't use any silicon at all on the water pump, intake manifold (well, at the ends) or timing cover gaskets, so I don't think anything could have gotten in there to plug it up.

I'm also buying a stock replacement radiator cap, whatever pressure that is.

Steve
 
the frustrations got to be killin ya at this point.... the water pump, pull it off or call miloden and find out how many blades that thing has
 
Yeah, its definitely getting to me.

I don't get enough chance to fool with the thing as it is and I don't want to spend the whole spring chasing my tail.

I think I'll pull it off and see what's in there. There doesn't appear to be an external part# anyplace and I'm not sure whether its a standard or high volume.

Of course I did an awesome job painting my front cover, pump and all that crap and its going to get jacked up when I pull it all apart (again).
 
If the fluid in the clutch fan breaks down it won't loosen up and pull a lot of air. Happened to me on another car. How freely does the fan spin without a belt on it? it should be really stiff. If it's already really loose then that could be your problem.
 
I got the pump from Summit. This sounds promising. Even if I would have bought the pump from the parts store, I would have bought the AC version thinking it was "heavy duty".

I will check the clutch fan for sure.

If the head gasket is blown, a grown man will be crying in my garage at some point.
 
the ol iron can take a bit of abuse, no doubt

do you have a pressure tester?
 
mopar340dave said:
the ol iron can take a bit of abuse, no doubt

do you have a pressure tester?
Click to expand...

I have access to one. So far, the oil isn't milky and the water isn't oily or bubbly, but the tester will tell the tale.

The time it got real hot, there was a drip at the bottom hose by the radiator though, and that's got me worried.
 
If you have the part number of that water pump call the manufacturer's tech line and ask them how many blades that pump has.

If you don't know the part number Summit keeps a history of your purchases so they would be able to tell you what you bought.
 
I have the same problem on my 360 (70 Duster), the pulleys are the problem on mine. I changed from a underdrive crank pulley to a OEM 6 1/2" od, and it helped alot, but didn't completely solve the problem. The combo that I'm using now still isn't correct, because the crank pullley (6 1/2") should be the same size or larger than the water pump pulley (currently 6 7/8"). Bottom line the waterpump/fan isn't turning fast enough at idle. I've been looking for a single groove 3" deep (72 later) pump pulley that is 6 1/2 od or perferrably smaller. No luck, anybody have one?
 
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