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TXmark
05-23-2015, 03:43 PM
I've been working on my hemi conversion for my '63 Hawk. I have the engine set up on a test stand, with a alum rad. electric fan, it's a '56 chrysler 331 poly block .060 over with 354 hemi heads and a mild cam, stock 180 t-stat. chev BB Weiand high volume water pump, stock crossover runs cool at 900 rpm, hot at 1600 rpm, pics attached, any ideas why its running hot:cool:440764407744078

r1lark
05-23-2015, 04:08 PM
Some quick 'out of the box' thoughts:
Any coolant passages in blocks and/or heads that have to be added and/or plugged when doing the conversion from poly to hemi heads?
Water pump impeller loose? (had this happen to me once.....)
Water pump made for a belt system that drives it in the opposite direction?
Was a verification made that all coolant passages had corresponding holes in head gaskets?

Keep us posted on progress, this is a really cool project! :!!:

clonelark
05-23-2015, 04:55 PM
Is there a Hemi forum? if so, maybe someone has ran into this problem. Might try a street rod forum also.

lark55
05-23-2015, 05:31 PM
Would a shroud around the radiator help the fan to pull more air? I am thinking that at 1600 rpm you are working the engine harder and it needs to move more air thru the radiator to transfer the heat.

jts359
05-23-2015, 07:02 PM
Hi Are you doing this inside ? That Elephant generates a lot of heat and you maybe pulling the hot air back thru the rad from the atmosphere in the garage , Ed

4653Stude
05-23-2015, 07:48 PM
Looks like the radiator is lower than the motor which will trap air in the heads. Pull out the thermostat and then pull top radiator off of radiator hold it above motor and fill the hose with water until you push the air out of the radiator. I have had a similar situation with an LS1. I like to never got the air out of the heads but eventually prevailed.

TXmark
05-23-2015, 08:16 PM
I moved the radiator up higher, thinking that would help it did not. heads and block are compatible, I'm next to the garage door with a 36"fan blowing on the engine. I believe I'm running too lean. I thought my carb was a 650 it's only a 600 opened up the air jets quite a bit, seemed to help I ran out of gas before I could really tell. The water pump is a Weiand short nose BB chevy, don't all engines turn the same way

I've posted on the HAMB and work with a guy who has worked on Mopar since he was a kid.
I think I'm running too lean, I'm definitely not running rich. running 93 octane ethanol free
This whole engine rebuild and setup is an area where I don't have a lot of experience.
I have found to build and early hemi you need deep pockets

Dick Steinkamp
05-23-2015, 09:07 PM
At 1600 RPM, your 331 needs 127 CFM at 83% volumetric efficiency. At 5500 RPM it still only needs 437 CFM. Your 600 should work fine with that motor. (BTW, is it a Holley or Edelbrock?)


http://www.4secondsflat.com/Carb_CFM_Calculator.html (http://www.4secondsflat.com/Carb_CFM_Calculator.html)

I'm not sure what you mean by "air jets". If you mean the idle mixture screws, the carb is off the idle circuit before 1000 RPM and those screws are not effecting the mixture.

With no load on the engine at 1600 RPM, it shouldn't be getting hot even if the mixture was way off. If you have one of those laser thermometers, check and see where it is getting hot. That might give you a clue.

Great looking motor! :!:

Corvanti
05-23-2015, 09:38 PM
Mark, i agree with just about everybody that has posted - but - have you run the engine without the thermostat to see if that makes a difference? may be a bad thermo.

not the same "animal", but when i had my Corvettes, i dropped down to a 160 thermostat. mainly since i was usually in stop & go traffic and the thermo wouldn't start closing until close to that temp.

a push fan added may help. you know more about these than i do. just things to think about.:)

Mike Van Veghten
05-23-2015, 09:52 PM
1. Ignition timing has MUCH MORE to do with the engine running hot than the apparent lack of fuel does, especially sitting in a stand..! If it were on the road going up hill and running hot, then one place to look would be the fuel delivery.
Lightly loosen the distributor, start the engine, rotate the distributor (I've forgotten the direction) and listen for the rpm to increase. Continue rotating the distributor until it starts to miss, then retard it...reverse the rotation about 1/8" on the outside diameter of the cap. Check the timing with a light and record for later use.

2. That fan, I doubt it pulls enough air. There other much better fans out there. Factory GM and Ford (Mustang & Lincoln) fans are one place to look.
Another good aftermarket fan is Delta PAG - http://www.deltapag.com/Technology.html
These fans were designed specifically for taxis in N.Y. city. They aren't too power hungry and have some fairly good science behind their design, (I've got two).

3. Did you put a bunch of Antifreeze in the mix ?
If so, cut the mix down to about 25% or 30% antrifreeze to 75% water. Antifreeze does not transfer heat to the radiator like just water does.

4. Make sure that with moving the radiator up, that you have no air pockets in the system.

Good luck.

Mike

TWChamp
05-23-2015, 11:20 PM
Mark, i agree with just about everybody that has posted - but - have you run the engine without the thermostat to see if that makes a difference? may be a bad thermo.

not the same "animal", but when i had my Corvettes, i dropped down to a 160 thermostat. mainly since i was usually in stop & go traffic and the thermo wouldn't start closing until close to that temp.

a push fan added may help. you know more about these than i do. just things to think about.:)

I agree that pushing air from the front should work better than pulling air from the rear, because when you push the air it becomes denser and should transfer more heat.

t walgamuth
05-24-2015, 06:43 AM
Seems like Mike may be on the right track with ignition issues. At idle all the other potential reasons seem unlikely to make it get warm.

TXmark
05-24-2015, 01:55 PM
I have tried the timing from 8 to 15 degrees, I believe it a combination of issues, fan, ignition and fuel mix
I checked for manifold leaks with starting fluid.
so a pusher fan is better, I don't know that's why I ask.

thanks for all the help

gordr
05-24-2015, 02:11 PM
You asked if all engines turn the same way. The only reverse-rotation car engine that comes to mind is the Corvair, and Corvair water pumps are mighty thin on the ground. But, and this is a big "but", there are many custom water pumps out there designed for serpentine belt drive, and at least some of those are made to turn in the opposite direction of engine rotation. You should absolutely verify that you have the right custom pump for the application. One other thing concerns me. There seems to be very little "wrap" of the belts around the water pump pulley, and the belts look a little slack in the pictures. Any chance the belts are simply slipping when the revs get up there?

Dick Steinkamp
05-24-2015, 03:27 PM
I have tried the timing from 8 to 15 degrees, I believe it a combination of issues, fan, ignition and fuel mix
I checked for manifold leaks with starting fluid.
so a pusher fan is better, I don't know that's why I ask.

thanks for all the help

My old Motor's Manual shows initial timing for that motor at 2 degrees BTDC (4 degrees BTDC for the power package. The earlier 331 hemi shows 4 BTDC). It could be you have too much initial spark lead (as Mike suggests).

The other thing that could be happening is that you have too much TOTAL advance at 1,600 RPM. If you have your vacuum advance hooked up, you will have your initial, centrifugal AND vacuum advance all in. Centrifugal advance is adding 14 degrees. Vacuum advance is adding 11.5 degrees and would not normally be in at this RPM unless you were running down the highway with light throttle with a lot of air going through the rad. Try disconnecting the vacuum advance.

Corvanti
05-24-2015, 06:40 PM
so a pusher fan is better

from i've read and having a pusher fan on my '63 Avanti with a switch to turn on as needed, i do think a pusher fan brings more "cooler" air in than a puller.

i believe Mr. Steinkamp and others are on to something regarding the timing issue.

junior
05-24-2015, 09:51 PM
I figure it's running hot because that HEMI is hot...pretty simple actually. lol... hope you get it to keep it's cool, as for suggestions I stumped (other than what other's have suggested.) It's going to be so COOL in a Stude! cheers, junior

sals54
05-25-2015, 02:26 AM
1. Ignition timing has MUCH MORE to do with the engine running hot than the apparent lack of fuel does, especially sitting in a stand..! If it were on the road going up hill and running hot, then one place to look would be the fuel delivery.
Lightly loosen the distributor, start the engine, rotate the distributor (I've forgotten the direction) and listen for the rpm to increase. Continue rotating the distributor until it starts to miss, then retard it...reverse the rotation about 1/8" on the outside diameter of the cap. Check the timing with a light and record for later use.

2. That fan, I doubt it pulls enough air. There other much better fans out there. Factory GM and Ford (Mustang & Lincoln) fans are one place to look.
Another good aftermarket fan is Delta PAG - http://www.deltapag.com/Technology.html
These fans were designed specifically for taxis in N.Y. city. They aren't too power hungry and have some fairly good science behind their design, (I've got two).

3. Did you put a bunch of Antifreeze in the mix ?
If so, cut the mix down to about 25% or 30% antrifreeze to 75% water. Antifreeze does not transfer heat to the radiator like just water does.

4. Make sure that with moving the radiator up, that you have no air pockets in the system.

Good luck.

Mike
I think Mike has nailed the checklist. But I would have to agree with most of the comments above as well.
But I would start with the easiest and cheapest first. Go with the timing and thermostat change first. Then check out a better fan situation. By the looks of it, you're not covering enough of the radiator with that fan, and secondly, are you sure you're pulling enough air with that fan? If you're driving at 60 mph, you'll be pushing a hekuvalot more air than that little fan is moving.
Good luck, it looks awesome.

ralt12
05-25-2015, 11:32 AM
You asked if all engines turn the same way. The only reverse-rotation car engine that comes to mind is the Corvair, and Corvair water pumps are mighty thin on the ground. .


You aren't kidding. Especially since they're air-cooled.

TXmark
05-25-2015, 11:49 PM
I know they all turn the same way, but someone earlier asked if the pump was running the wrong way, which is possible since some serpentine drive pumps are driven from the back or smooth side of the belt. That's not the case in my problem. I'm running a weiand BB chevy short pump which are only made to run CW

t walgamuth
05-26-2015, 07:56 AM
Some Hemis were built to turn opposite direction to run as a pair in boats. (I hear).

8E45E
05-26-2015, 08:07 AM
I would also possibly suggest an external oil cooler in front of the rad.

Craig