Turning torque for engine

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Slappy

Slappy

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Good afternoon guys. You guys have helped me so much in the past. I’m hoping you can help me with this problem. I have a 72 Dodge Demon with a 360 small block engine. The engine is 10 1/2 to one compression according to the machine shop. Aluminum heads, roller, rocker, arms, etc. I’m having a problem with the car running too hot. I’ve been down this road a lot with you guys. I’m to the point where I believe it’s something internal. I can turn the motor over by hand fully assembled. Plugs, installed rocker, arms installed, etc.. I’m trying to figure out how hard it should be to turn this engine over by hand. It doesn’t seem too tight, but I’m not sure how tight it should be. The engine runs fine has no other issues other than overheating. I’ve been through all of the cooling system several times with no solution. So I’m down to something internal. I did a leak down test no head gasket problems. I also have good compression . Does anyone have a torque value on a fully assembled engine? Thanks for your help.
 
Radiator type /size? rad cap? fan(s)? coolant type? timing? How soon does it overheat? highest temps? in traffic and around town or highway or both? Are you saying the motor is or is not in the car?
 
I have already been through the cooling system diagnosis I have a three row champion radiator two electric fans . I’ve tried different water pumps, thermostats fans, etc. it’s not the cooling system. I’m just looking for a turning value for turning the motor over. The engine is in the car. The transmission is in neutral, fully assembled belt on all accessories in play
 
It takes a little while to overheat. Once it starts to creep up, it will go as high as 220 maybe higher and I shut it down. The hoses are like rockhard seems like too much pressure. I’ve done head gasket test. Three times. All three times negative. It’s not a head gasket problem. It overheats whether going down the road or in the garage doesn’t matter. It will always run too hot. Fans come on at 180 and stay on.
 
Without the plugs in it, I would say it should turn without making a click type torque wrench click set between 25 - 35 LBFT.
 
Slappy said:
It takes a little while to overheat. Once it starts to creep up, it will go as high as 220 maybe higher and I shut it down. The hoses are like rockhard seems like too much pressure. I’ve done head gasket test. Three times. All three times negative. It’s not a head gasket problem. It overheats whether going down the road or in the garage doesn’t matter. It will always run too hot. Fans come on at 180 and stay on.
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Problem caused by incorrect timing maybe??

Where do you have it set?
 
I have tried several timing situations and nothing seems to work. Do you have a suggestion? I’m willing to try anything.
 
Carb jetting or HardBlok in the water jackets ? Compression test may show if any excess ring friction in the bores is causing heat and wear and checking a magnetic drain plug for iron particles or even an oil analysis can find other friction/wear/heat sources.
 
Check lower hose for sucking shut? Does it have a spring in it
 
Locomotion said:
Carb jetting or HardBlok in the water jackets ? Compression test may show if any excess ring friction in the bores is causing heat and wear and checking a magnetic drain plug for iron particles or even an oil analysis can find other friction/wear/heat sources.
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I have Holley sniper fuel injection . The timing is not controlled by sniper though . Oil analysis came out good. Makes no sense right?
 
Slappy said:
Old style pointer?
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Either that or a click type will be fine for what you're doing. You don't need anything fancy. All you're wanting is to get in the ballpark.
 
Go out and measure your pulleys. They need to be the same size or better yet, the crank pulley needs to be larger.

You need the pump to be 1:1 at the slowest. Overdriven is better.

Engines don’t make themselves overheat.

If the tune up is close it shouldn’t get hot.

I’d say loose the electric fans but most guys won’t do it. Unless they are very good fans they are just getting in the way.
 
Seems you've been through everything and the tighter the engine, the more heat it creates. So, how about the gauge itself.
 
Shot in the dark...

Bad, wrong or incorrectly installed head gasket blocking water passages?
 
Slappy said:
I have already been through the cooling system diagnosis I have a three row champion radiator two electric fans . I’ve tried different water pumps, thermostats fans, etc. it’s not the cooling system. I’m just looking for a turning value for turning the motor over. The engine is in the car. The transmission is in neutral, fully assembled belt on all accessories in play
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Just want to clarify, when you say “fully assembled belt on all accessories in play”, is it just one serpentine belt?

Only reason I ask is that if this is the case, are you rotating the pump the wrong direction relative to the impeller blades?

Got a picture of the belt(s) routing? Also wondering if you have one really long v-belt going around multiple things and it’s just slipping on the water pump pulley and not driving it fast enough because it’s not making enough contact.

Last thought would be casting sand or sediment from hard water inside the block, or as another asked, hard block.

Hope you find your issue!!!
 
Have heard of some people having issues with 3 core over 2 core radiators due to less surface area of the 3 core.

As oldmanRick said, checked the gauge and see if it reading correctly. They do fail sometimes. Would also take a temp gun and checked the temp.
 
Turning torque will be different, depending on if the spark plugs are installed, and if the valve train is installed. More compression and more valve spring pressure will increase the turning torque. I have assembled engines that would turn over at 12 inch lbs, until the spark plugs and push rods were installed. So I would think that if you can turn the engine over in the car with a 1/2” ratchet, you should be ok
 
Just out of curiosity, have you checked to see if the outer ring on the balancer has spun and giving you false timing stats?
 
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