Overheating 360 new engine

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EDIT TO REMOVE WRONG INFO

I think someone said that the March Pulley system you are running is at about 0.90:1 so OK for 8 fin. But if you had a 6 fin it might not move enough coolant.

If you scored one with the fin backing disc, a little better yet.
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Are your sure about that? I thought the A/C cars generally had 6 blade pumps, but were over driven to increase coolant flow (and fan speed).
Edited to remove wrong Info. I got them backwards. But in almost all the AC and non AC "A" engines I took apart they all has 6 vain pumps, Even the date coded 1978 pump on my non AC 78 LRT.
 
Ok guys got back to working on the car this morning. I found out that the water pump that’s on the car is a six blade. I also found out the exact measurement of the water pump pulley, which I think is small, which could be a factor as well but hopefully with this new eight blade pump, it may help here are the pictures . No blockages in the water pump passages that I can see.

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The SMALL water pump pulley is for FASTER fan speed and impeller speed. Kind of what is needed with a 6 vane impeller. To slow them down you go larger pump pulley or smaller crank pulley....

Back when I use to get the DC newsletters and Magizenes, I think Larry Shepard said the 8 vane cost like 4-5 HP on a 340 and 360 but the consensus was on a street car or truck it was worth it.

Gain 5 HP is great for bragging rights. Lose 5 HP but gain more cooling is better in my book.
 
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Ok here is what I have . The engine still got to 210 before I shut it down . Took about 25-30 minutes in the garage. This actually is double the time before the new pump. I recently was at a car show and I went digging into everyone’s cooling systems . They were all over the place . Water pump pulleys were all different sizes , radiators were different , stock fans electric fans, shrouds no shrouds, etc . I did talk to a few people at their cars and all said no overheating. As I stated a few pages back I have discovered the LS of the engine is hotter. Is it possible to have a head gasket upside down and still seal? How about using a magnum engine gasket on an LA engine? I haven’t had these apart enough times to know. Thanks again for the help.
 
Ok here is what I have . The engine still got to 210 before I shut it down . Took about 25-30 minutes in the garage. This actually is double the time before the new pump. I recently was at a car show and I went digging into everyone’s cooling systems . They were all over the place . Water pump pulleys were all different sizes , radiators were different , stock fans electric fans, shrouds no shrouds, etc . I did talk to a few people at their cars and all said no overheating. As I stated a few pages back I have discovered the LS of the engine is hotter. Is it possible to have a head gasket upside down and still seal? How about using a magnum engine gasket on an LA engine? I haven’t had these apart enough times to know. Thanks again for the help.
Slappy refresh my memory, what radiator and fan are you using?
 
After I get things together and test run it, I will re-post.
I read one post where you said you have a "regular" thermostat. I don't know what that means. You need a high flow thermostat. I recommend a 160 high flow. It you have a standard flow thermostat, you may as well throw the high volume water pump in the ditch, because the water still has to go through a standard flow thermostat. It's a literal choke point. The goal with a good cooling system is to get the coolant out of the engine as quickly as possible before it has a chance to heat up. Same theory with the 160 thermostat. If the coolant is allowed to get out of the engine at a lower temperature, it has that much less chance of over heating.
 
Going in a different direction, since this is a pretty new motor. My freshly rebuild bbm was giving me fits with overheating so I tried shroud, fan spacer, water wetter, auxilary pusher fan, hi flow thermostat etc and finally found my cam was cut 5 degrees retarded. Degreed it and all my problems stopped. Best of luck.
 
I read one post where you said you have a "regular" thermostat. I don't know what that means. You need a high flow thermostat. I recommend a 160 high flow. It you have a standard flow thermostat, you may as well throw the high volume water pump in the ditch, because the water still has to go through a standard flow thermostat. It's a literal choke point. The goal with a good cooling system is to get the coolant out of the engine as quickly as possible before it has a chance to heat up. Same theory with the 160 thermostat. If the coolant is allowed to get out of the engine at a lower temperature, it has that much less chance of over heating.
Yes running a standard 195 and I drilled two holes in it . Will try the high flow .
 
Yes running a standard 195 and I drilled two holes in it . Will try the high flow .
Drilling the holes does nothing for over heating. All that is for is to prevent any trapped air when you replace the thermostat. It's a good trick, though. If it was mine, I would put a Stewart 160 high flow thermostat in it and tune for the earlier opening thermostat. The earlier it opens, the quicker you get the coolant out of the engine, which is what you need to do.
 
Drilling the stat makes it worse because it reduces the pressure in the system. The pressure reduces localised nucleate boiling [ air/steam bubbles ]. The reason that drilled stats appeared on the scene is that Stewart Components, maker of race water pumps, eliminated the bypass in some of their pumps. To ensure there was pressure relief in case of a stuck stat so that the engine would not blow out a Welsh plug, the stats were drilled. Your engine has the bypass, as do all production engines.
 
Drilling the stat makes it worse because it reduces the pressure in the system. The pressure reduces localised nucleate boiling [ air/steam bubbles ]. The reason that drilled stats appeared on the scene is that Stewart Components, maker of race water pumps, eliminated the bypass in some of their pumps. To ensure there was pressure relief in case of a stuck stat so that the engine would not blow out a Welsh plug, the stats were drilled. Your engine has the bypass, as do all production engines.
No it doesn't. If that was the case, then why even have the thermostat open? Are you off your meds again? Do I need to come down there and take you out drinkin?
 
Rusty,
If measure up all the holes in the head gasket/block/head [ I have done it ] , you will find their combined area exceeds that of the stat opening.....by a large amount. The stat becomes the restriction in the system that allows pressure to build up behind it. The pressure suppresses steam/air bubbles at hotspots [ such as near the exh valves ] that build up. Since air is a poor conductor of heat, anything that reduces 'air' in the cooing system & replaces it with coolant is a good thing. The cooling system is a balancing act, balancing flow & pressure.

You can come down anytime. Maybe I should try your meds.....
 
Rusty,
If measure up all the holes in the head gasket/block/head [ I have done it ] , you will find their combined area exceeds that of the stat opening.....by a large amount. The stat becomes the restriction in the system that allows pressure to build up behind it. The pressure suppresses steam/air bubbles at hotspots [ such as near the exh valves ] that build up. Since air is a poor conductor of heat, anything that reduces 'air' in the cooing system & replaces it with coolant is a good thing. The cooling system is a balancing act, balancing flow & pressure.

You can come down anytime. Maybe I should try your meds.....
I'm sure we'd have a good time on any meds, liquid or otherwise! lol
 
Living on the west coast things are a bit steeper. This is about 2 miles from my home and the only way I go into town unless its raining. Steering with the throttle is not fun on a steep hill. See the inset on bottom left for how twisty the road is.

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Hell yeah! We did a west coast cruise in our RV this summer. Hit an 18% grade for 5km with retarded 90* switchbacks. Smoked out the brake (even with max engine braking). LOL......We googled the flattest way out of British Columbia on our way home.
 
So there was a 6 vane pump and a 195° thermostat. It just doesn’t make any sense as to why it runs at the temp it does....none. :D
Seriously, you got the pump sorted now pitch that thermostat and run a 160° or no more than a 180° Hi Flo as mentioned above. I bet it’ll run under 200°
 
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if the block passages are full of sludge and the heads etc? OP you could flush it out remove the block plugs on each bank see what comes out...Ive seen it where ya remove the block plugs and nothing comes out they are so rust blocked...its a circulation problem but if the pumps dont fix it its somewhere else....
 
So there was a 6 vane pump and a 195° thermostat. It just doesn’t make any sense as to why it runs at the temp it does....none. :D
Seriously, you got the pump sorted now pitch that thermostat and run a 160° or no more than a 180° Hi Flo as mentioned above. I bet it’ll run under 200°
I put a "factory recommended" 195 ` in my 02 Ram 5.9. In Tampa, the thing was replaced after the first run...
 
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