New Aluminum Radiator, Still Over-heating!!!

[Moparman01]

After ever thing that i've done to try to figure out why my 440 likes to over heat, i finally broke down and bought a new aluminum radiator, it was the last thing to try before i have think it's an internal engine issue. Put it all together, on a 90* day outside, went for a ride around the block and temp went up to around 215* after about a 1 mile and a half of driving, would continue to rise if i keep driving, it's been up to 230* before. Yes, i filled the rad. and burped out any air the system, so that's not the issue, plus you can plainly see good coolant flow thru the rad. Here's the luandry list of all the things i have done, incuding the new radiator:

1. Tried multiple t-stats, 160* and 180*, currently have a 160* in it now.
2. New hoses, to and bottom, both have springs in them, no collapsing.
3. Different pressure radiator caps. have a 15 or 16lb on it now (i'll have to go back and look).
4. Checked and re-checked timing, even had the car profesionally tuned, timing is around 10* BTDC at idle.
5. Had a Chrysler 3 row 26" radiator re-cored and tested, had a fan shroud too!
6. large 7 blade fixed fan, almost went to a clutch fan, but heats up more while driving than just sitting.
7. New water pump, tried a high flow aluminum pump from MRE first, now went to a new OEM type pump, with Mancini alum. housing, blades are going the right direction.
8. As mentioned above, new 26" 2 row cross flow aluminum radiator, can't find a shroud that will fit it tho, the shroud will only "slow" down the over-heating, i've tried it before...
9. Tried all the "water wetter" trype products
10. I run a 50-50 mix of coolant to water.
11. Have had 3 different aftermarket temp guages, incluging the stock dash guage!

So now i think it's in the motor, head gaskets have been suggested but the engine runs great, no water in the oil and no wierd smoke out the tail pipes, but a friend of mine said it could be a small blow in between the cylinders around a water jacket, cuasing extra pressure and heat to enter the cooling system. Anyone have any other suggestions before i tear the heads off the car, i'm gettin tired of workin my butt off only to still have the same problem. The motor is not radical, just a mild 440 with a healthy cam, Eddy intake and carb, and stock HP exhuast manifolds (no headers). If the heads have to come i'll do it but i'm not lookin foward to it!
 

[BBKNARF]

I don't know if this will help you  http://www.dodgecharger.com/forum/index.php/topic,60599.msg675707.html#msg675707

[1970Moparmann]

I don't know if this will help you  http://www.dodgecharger.com/forum/index.php/topic,60599.msg675707.html#msg675707

I agree! 

Your doing everything correct in terms of trouble shooting.  Spend the hour and take off the water pump housing and check the ports!  I had this issue and put on a Mancini housing for $79 and it's all good now.

[Moparman01]

I don't know if this will help you  http://www.dodgecharger.com/forum/index.php/topic,60599.msg675707.html#msg675707

I agree! 

Your doing everything correct in terms of trouble shooting.  Spend the hour and take off the water pump housing and check the ports!  I had this issue and put on a Mancini housing for $79 and it's all good now.

Forgot to mention that...i already have the a Mancini alum. housing, got when i got the water pump!!

[elacruze]

Hmm.

Got pressure in the hoses when hot? I've seen a jillion radiator caps that have no spring in the vacuum valve, brand new.

What's your engine build? Compression, Cam, Trans? Cooler in radiator?

[Moparman01]

Hmm.

Got pressure in the hoses when hot? I've seen a jillion radiator caps that have no spring in the vacuum valve, brand new.

What's your engine build? Compression, Cam, Trans? Cooler in radiator?

Don't really know the exact build, bought the engine from a friend of mine. What i do know is it runs fine on 93 pump gas so the comp. isn't too high, has the old Mopar "509" cam in it, 727 tranny and i run the tranny fluid thru both an external tranny cooler and the radiators' cooler, stock "HP" exhuast manifolds, Eddy intake and 750 carb. Here's the real kicker, i let a friend of mine borrow the engine for his 68 Charger (while the engine shop was building his) and he had no over heating issues, we drove his car 3 hours north on a hot July day to a show, ran around 180* or so all the way up and back, it didn't start heating up till i put the motor in my car!! I've done all i think of, now i gotta rip into the motor...fun.   

[elacruze]

Before you go so far, bypass the transmission cooler in the radiator. A hot transmission can put a ton of temperature in the coolant. Easy to do, costs nothing and there's a flyer that it could help.

If the engine didn't run hot is his car, only the differences between the two can make it hot in yours.

[W4ATL]

Hmm.

Got pressure in the hoses when hot? I've seen a jillion radiator caps that have no spring in the vacuum valve, brand new.

What's your engine build? Compression, Cam, Trans? Cooler in radiator?

Don't really know the exact build, bought the engine from a friend of mine. What i do know is it runs fine on 93 pump gas so the comp. isn't too high, has the old Mopar "509" cam in it, 727 tranny and i run the tranny fluid thru both an external tranny cooler and the radiators' cooler, stock "HP" exhuast manifolds, Eddy intake and 750 carb. Here's the real kicker, i let a friend of mine borrow the engine for his 68 Charger (while the engine shop was building his) and he had no over heating issues, we drove his car 3 hours north on a hot July day to a show, ran around 180* or so all the way up and back, it didn't start heating up till i put the motor in my car!! I've done all i think of, now i gotta rip into the motor...fun.   

If the motor did not overheat in the other car then I would doubt it is a motor related issue. It has to be outside the motor (hoses or radiator.) With the motor in the other car you know that the thermostat and water pump are good. Do you get good air flow from the fan? The air pressure at idle should be enough to hold a paper towel or piece of paper to the radiator.

[68 RT]

I would say you have an air flow problem. Do you have a/c? If so check condensor to see if it is plugged. Also is you fan on the right way? I bought a 69 442 that would get hot while driving. Found the fan was on backwards. Dou you ever have your radiator boil over? How far will the temp go up while driving? If you stop driving does the temp go back down?

[firefighter3931]

I bet it's a tuning issue. That cam will want lots of initial timing....at least 20* at idle. The carb is probably lean as well.....Eddy carbs don't work well with large cams.


Ron

[Moparman01]

Nope, that car doesn't have A/C. When my buddy had my engine, that was about 5 or 6 years ago, plus it spent a year after that out of his car before i put in mine, so it wasn't any quick turn around with the motor. I've had the temp. reach the 230* mark before on a hot day after about 15 miles of driving, no the temp will not go back down while idleing. If i go out on a cool day/night, like 60*'s or 70*'s it will usaully only get up to a round 200* driving across town to one of our cruise nights. Fan is on the right way, has to have the right size pulley set up too, i have 3 other non-over heating big blocks to compare too. Wow, 20* initial timing??? i'm 10* with it, runs good, and thats where my buddy had it set as well. The carb is running a little rich but overly rich. Tomorrow night, just for grins and giggles, i've knocked out the center of an old t-stat and i'm gonna try it, doubt it will work but it's worth a shot, something i haven't tried yet.

[elacruze]

My 440 with 11:1 and .509" cam likes about 18* initial timing. Most people say it's too much compression on open chamber heads but it works great, if you have less you could use more timing.


I'm thinking along with Ron, you don't have enough initial timing. Late timing puts a lot of heat in the exhaust port. Still, if it was run that way in the other car, it should not make so much difference in yours.
It's also a possibility that you have some scale in the head gasket coolant passages, restricting flow to the heads and overheating the coolant locally.

[68X426]

  Timing.

No guess work here, even the 68 Service Manual lists timing as the #2 possible cause, after blocked air passages. You got to at least test more timing. Those factory guys knew stuff.

[Moparman01]

Thought i had it figured out tonight. I pulled out the t-stat and put in a restrictor (knocked out the center of an old t-stat that was no good). I let the car idle for a 15 minutes in the garage and it stayed around 150*. So out to the street with it, as i was driving around it was holding nice and steady at about 165*-170*, only went about maybe 2 miles at the most (it was starting to sprinkle) but it was holding, when i pulled in the drive way, pretending i was sitting at a light or something, the temp started to climb pretty fast...180*...190*...200* as i was backin it back around to the garage. With the car stopped and holding my foot on the gas at about 1600 or so rpms, theh temp came back down to 190*. It was only in the mid 70's air temp out side tonight, probably would get hotter if the air temp was warmer. I really don't like not having a t-stat, but it was worht a shot before i pull the heads off and replace the gaskets. Not know the exact specs on the cam, other than being told it's the "509", i dunno if i want to take the time up to 15* or 20* and risk hurting the engine...   

[Rolling_Thunder]

I bet it's a tuning issue. That cam will want lots of initial timing....at least 20* at idle. The carb is probably lean as well.....Eddy carbs don't work well with large cams.


Ron

Agreed -  timing and lean condition causes a lot of heat

[Charger´69]

Not know the exact specs on the cam, other than being told it's the "509", i dunno if i want to take the time up to 15* or 20* and risk hurting the engine...   

No, you won´t hurt engine if you try that 15-20 BTDC. It shouldn´t start pinging when idling and normal driving, only case is that if your max advance go too high (over 35-40 degrees) it might start to ping and you can hear it when you floor it. If it doesn´t start pinging in any case and temperature stays enough low you won´t hurt your engine 

[firefighter3931]

being told it's the "509", i dunno if i want to take the time up to 15* or 20* and risk hurting the engine...   

The 509 wants lots of initial timing....give it !  The idle will clean up and you will make more manifold vacuum. Just check the total timing to make sure you're not exceeding 38* and disable the vacuum advance if you're still using it. 

Ron