Overheating 360 new engine

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I get a kick outta how many folks forget about all the parasitic power loss thru friction, belts, bearings, brushes, magnetism, drag, etc, etc. that a water pump mounted fan doesn't have.
Clutch fans don't spin over 4k ish, and sorta freewheel when hot.
Each has it's advantages, mounting being a deciding factor .
Electric fans do take power, it's not free !
My racecars have significant rpm loss when the fans kick on !
jmo

Nobody said electric fans were "free". But the difference in running a 60 amp alternator and a 100 amp or even a 200 amp alternator isn't that much. There's very little difference at all unless the fans are actually running and requiring the higher amperage, the difference in friction from the belts, bearings, brushes etc is almost nothing unless you're pulling the higher draw. You have to run an alternator regardless, so you're not going to get rid of friction from the belt, bearings, etc.

And it depends on the type of clutch fan. Simple hydrostatic clutches never free wheel. Some of the better thermostatic clutches can do better, but most of them aren't 100% free wheeling either. And that's assuming a clutch fan is being used, seems like most of the argument in this thread is guys running straight mechanical fans that will be 100% all the time.

There are advantages and disadvantages to both, the bottom line is that in either case you have to set the system up correctly. Both mechanical and electric fans can be inadequate if set up improperly.

A couple things come to mind and this is my ante or $.02...at first it sounds like a restriction int he water jackets in the block or heads, but I have to be honest ive never enncountered this no more than an extremely sludged radiator or a bad thermostat...second, That belt drive, is the water pump spinning the right way? are you sure? really sure...? I have seen bad water pump impellers that act like you describe OP. I forget what car had plastic impellers and they would grenade causing an overheat, i think it was Ford...second Ive seen completely rusted out impellers act this way, but I would assume yours is a new water pump so it could be spinning backwards. Good luck...

This water pump spinning backwards thing again.

Guys, you know that in order to run a Magnum water pump with a reverse rotation you'd need the magnum timing cover too right? March does not specify a reverse rotation water pump with their LA kits, and it's a big change to make. In fact, you can go right to March's website and download the instructions for their kit. It has a nice little diagram in it, which shows the belt routing and the normal LA water pump rotation is maintained. In the pictures the OP posted you can clearly see the belt on top of the water pump pulley.
Screen Shot 2022-09-30 at 11.48.04 AM.png

Or go an download the instructions yourself and take a look...
Chrysler 318/340/360 : Style Track : Includes alternator and air conditioning with optional power steering
 
.............................Electric fans do take power, it's not free !
My racecars have significant rpm loss when the fans kick on !
jmo
Electric fans, especially big ones will drop the RPM's when kicked on as they are drawing a lot of alternator power.

But do you use the fan at the Christmas Tree?

Are the fans on going down the Quarter or Eighth?

Most likely NO. No need with airflow going thru and shuch a short time.
But I bet you kick them manually on once you pull off the track.

But that mechanical driven propeller fan driven by the crank is sapping power down the track 100% of the time. It might be freewheeling somewhat if its a clutch fan but they never freewheel 100% and the mass of rotational weight is still there.

A ridged mounted "Flex" fan is kicking 100% @ 100% of the time.

To each their own. If you are passionate about mechanical fans, no one will change your mind. The little 4 blade ridged fan in my 65 Barracuda with a 318 worked wonders. But it was all stock.
 
I wonder if any of this is helping the OP. I'm guessing not.
It seems OP is in Florida and it may be some time before we hear anything.

OP has an electric fan and no room to fit a mechanical clutch fan unless he dumps his 'March' pulley system. He most likely will not dump the $$$$ invested in his March pulleys.

So its beating a dead horse by some that keep going on and on and on with Mechanical Fan comments.

Other comments about the mechanical conditions inside his engine are still good. Valve adjustments, Piston ring gap butting, Core shift and the overbore too close to water jacket, Plugged or rusted water passages, oil pressure not good causing bearings to overheat......

OP is a former ASE mechanic so most of the comments about Electrical Fans should help when he can get back to it.
 
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And I know 72bluNblu is using a "Dakota" Control box but for those that want to do a Contour fan with simple wiring, well as simple as two relays goes, here is a wiring diagram the OP may check out.

You can add a toggle switch between the Ignition and pin 85 of the left relay to shut off the fans while running the 1/4 mile. Put a lit one in so you can see its off. OR, put a normally open push button on the shifter so when you push the button the fans cut off, finger off and fans come on.

I could draw one up adding a 3rd relay for AC control.

EDITED to add 50 amp blade fuze to drawing. Must have safety
Contour Two Speed Relay.png
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Slappy, I can answer your question in post #22. Buy a 18-19" mechanical fan.
 
As I said earlier in this thread, sometimes the cause of the problem [ o'heating in this case ] cannot be found, despite best efforts.


I know of a Suzuki Swift that had an engine check light that kept lighting up. Everything in that car that could possibly cause the problem was changed but the problem persisted: new engine, all the sensors, wiring harness, etc. Suzuki gave the customer a new car & the old one was shipped back to Japan.
 
Slappy, I can answer your question in post #22. Buy a 18-19" mechanical fan.
Will that 'Super duper' 18-19 inch mechnical fan fit his March pulleys and the limited space to the radiator core?

Slappy is in Tampa Florida and most of that area is under 2-6 meters of water from the Hurricane.
 
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72blu.
6000cfm from a mech fan. Read what I said in post #65.
Yes, I read what you said. I haven't seen 6,000+ cfm published for a regular mechanical fan that would fit one of these cars, so frankly I asked you to back up your claim.

Most of the OE mechanical fans I've seen specs for that work on these cars are in the 5,000 cfm range at max flow, which is also usually closer to 4k rpm, not idle. Makes a BIG difference.
Slappy, I can answer your question in post #22. Buy a 18-19" mechanical fan.
I answered it in post #16 with a better solution for the OP, if you want to play that game.

Suggesting a mechanical fan for a guy asking for an electric fan that will move enough air to cool his car isn't really helpful. There are perfectly capable electric fans that will do the job.

As I said earlier in this thread, sometimes the cause of the problem [ o'heating in this case ] cannot be found, despite best efforts.


I know of a Suzuki Swift that had an engine check light that kept lighting up. Everything in that car that could possibly cause the problem was changed but the problem persisted: new engine, all the sensors, wiring harness, etc. Suzuki gave the customer a new car & the old one was shipped back to Japan.

Lol. First, a Suzuki Swift is a relevant example how?

And second, there was a problem that wasn't found. This is physics, not magic. The people looking for the problem just weren't capable of finding it and Suzuki cut their losses rather than continue to pay for failure. That's incompetence, not an unsolvable problem.
 
I am confused as 240 is hot and 250 is overheating
195-210 is where the temp should run no matter what. It is not 1970
215 is cause for concern but look in the right place for the fix
The cooling system is not problem yet
The answer is related to
The exhaust temps engine running and engine off are all over the place. The two middle cylinders have a 100f difference than the end ones both banks with the left side was considerably hotter than the right side
 
I am confused as 240 is hot and 250 is overheating
195-210 is where the temp should run no matter what. It is not 1970
215 is cause for concern but look in the right place for the fix
The cooling system is not problem yet
The answer is related to
The exhaust temps engine running and engine off are all over the place. The two middle cylinders have a 100f difference than the end ones both banks with the left side was considerably hotter than the right side

Physics haven’t changed since 1970. Unless you are trying to light the cats and reduce your carbon footprint 210 is too hot for making power.
 
Physics haven’t changed since 1970. Unless you are trying to light the cats and reduce your carbon footprint 210 is too hot for making power.
no no grasshoopper
today's fuel does not burn well below 195...we tune cars over here, instrumentation does not lie. 35 yrs tuning cars. My cars are always faster than the others. Below 195 the fuel collects on the intake surfaces and burns off n the cruise mode. We have data, real instrumentation and experience, you the seat of your pants only for experience.
 
I am confused as 240 is hot and 250 is overheating
195-210 is where the temp should run no matter what. It is not 1970
215 is cause for concern but look in the right place for the fix
The cooling system is not problem yet
The answer is related to
The exhaust temps engine running and engine off are all over the place. The two middle cylinders have a 100f difference than the end ones both banks with the left side was considerably hotter than the right side
He said in one post on here that it continues to get hotter.
 
Physics haven’t changed since 1970. Unless you are trying to light the cats and reduce your carbon footprint 210 is too hot for making power.

Physics hasn't, but technology has. Coolant has changed, radiator pressures have changed, fuel has changed, tuning has changed (EFI and computer controls), the list goes on and on.

NASCAR's run "coolant" temperatures at ~300°F, are they trying to reduce their carbon footprint?

A factory 6.4 L hemi runs a 203°F thermostat, and that engine makes as much or more hp than what a lot of folks have in their classics and it will do 100k+ miles no problem.

It absolutely matters how your engine is being used, how it's set up, and how it's tuned. Saying "210°F is too hot for making power" is just silly. Yeah, maybe for a Pro-stock car, but not for a NASCAR or a factory 6.4.

Bottom line is on a street car 210-215°F is nothing to worry about as long as it can maintain it.
 
With the temputures on the header tubes being 100 degrees hotter on the center two and the hottest on the left bank tends to tell me valve lash is screwy or lifter preload is too much.

I have found that some new cams have a smaller base circle. If he used longer pushrods for one of these new cams on an older cam.....
 
no no grasshoopper
today's fuel does not burn well below 195...we tune cars over here, instrumentation does not lie. 35 yrs tuning cars. My cars are always faster than the others. Below 195 the fuel collects on the intake surfaces and burns off n the cruise mode. We have data, real instrumentation and experience, you the seat of your pants only for experience.

LOL. If you can TUNE you don’t need to run those high temps.
 
Physics hasn't, but technology has. Coolant has changed, radiator pressures have changed, fuel has changed, tuning has changed (EFI and computer controls), the list goes on and on.

NASCAR's run "coolant" temperatures at ~300°F, are they trying to reduce their carbon footprint?

A factory 6.4 L hemi runs a 203°F thermostat, and that engine makes as much or more hp than what a lot of folks have in their classics and it will do 100k+ miles no problem.

It absolutely matters how your engine is being used, how it's set up, and how it's tuned. Saying "210°F is too hot for making power" is just silly. Yeah, maybe for a Pro-stock car, but not for a NASCAR or a factory 6.4.

Bottom line is on a street car 210-215°F is nothing to worry about as long as it can maintain it.

I realize there are times when engine temperature needs to be higher. Emissions is one. When you want to make power, you lower the temperature and raise the compression ratio.

You have to look at everything. Just saying 200 is best is not true.

Also most guys can‘t get the temperature down, as exampled in this thread. So rather than start over and get control over the temperature the easy button is say 200 is good enough.
 
Hello guys I'm having an overheating issue. Little background info first. I was a master ASE tech for 30 years this one has me stumped. I have had this car at two separate shops also. Here are my engine specs for the cooling system. I have a champion 3 row radiator. March serp belt system, 180 deg t-stat, stock water pump, 2 12 inch electric cooling fans mounted diagonally, vintage air system, autometer pro comp ultralite gauge, also Edelbrock aluminum rpm heads (60779). The engine has had a few different radiator caps. The current one is a stant 16lbs. Engine has less than 200 miles due to this issue. Forgot to mention this is an LA360. ..........
^^^^Here is his base line of whats inside. Twin 12 inch fans. The big 3 core radiator and the March Pulley system makes it too tight for a mechanical fan.
.........First I will start with the shop experiences. First shop stated that my carb was running to rich and causing the overheat issue. I took it to another shop and they said the same thing and tried to work on the brand new out of the box holley carb. This just made it worse running. I went ahead and added a Holley sniper EFI set up on. What a difference in runability and power!
Then Carb info given to him was bogas. Running too rich will normally not run hot but can run hot in the header tubes when unburnt gas is still burning. He then put a Sniper EFI on and that helped on power but still over heated. ........
........Engine is still running hot. I have tried several different thermostats ranging from 160-195. 2 Different water pumps, 2 different electric fan setups. I had all the engine parts IE block and heads, crank ect checked at a local machine shop. Block was bored 30 over. Head gaskets have been tested chemically 3 times and all 3 times negative. The heads were not in the box but were new never used. But some small port work was done on them. This is why the machine shop checked them for me.
360 block bored 0.030 over. Aluminum heads, 2.02 and 65cc chambers, slight port job. Tried different thermostats. No head gasket leaks
.......One weird thing did happen. One of the freeze plugs on the left side of the engine blew out. Both times the engine was at a higher rev. I put a third plug in and it felt like it went in to easy so I JB welded it in. I know this method is not professional but aside from taking the engine out it was easier. No more issues with that plug. I should mention also that no oil or coolant appear to be mixing in the engine or radiator. I also had an oil analysis done and that turned out ok so far.
Core plug popped out two times, JB Welded on third try. Lots of water flow.
..........I decided today was the day to look deep into the issue. The starting coolant was 89f . I live in Florida. I went ahead and ran a suitable fan in front of the engine. The first temp check was gauge read 150f and my two infrared temp guns read 134F. At 180f both cooling fans came on and water was flowing well in the radiator. Next temp reading was 194f at the gauge and the gun read 184F. At this point I stuck in a thermometer directly in the coolant. I left the coolant thermometer in until 205F then I put the cap on. Temperature continued to rise on the gauge and on the gun until I shut the car down around 215F.
Seems like good water flow. Air flow suspect even with two 12 inch electric fans.
.......I did notice that the exhaust temps engine running and engine off were all over the place. The two middle cylinders were as much as 100f difference than the end ones. This was true for both banks. The Left side was considerably hotter than the right side. To give you an example I have my MSD box mounted with an air flow gap under it on the inner fender well and it was 147f with the hood open. The master cylinder was 160F.
Now what would cause the header tube temps to be so different? This was with the hood open during his tests. He does not give the temp readings on the high center tubes. He also has not said what his aircleaner type is and if its the common "Chevy" hotrod open filter, and the master cylinder is 160F then he is sucking a lot of HOT air into the engine.
.......Not sure if the blowing out of the freeze plug was a sign. Bad Machine work?? EXhaust temps have me baffled as to why they are all over the place. I dont know if the engine block has some sort of flow issue. Heads issue?? I did order a cylinder leak down tester which will be my next task. I can watch the radiator for bubbles with it for head cracks ect. The car runs great accept too hot.
In some later posts he did some testing with other members on here and was working toward a fix... And the Hurracane Ian hit Tampa Flordia.
 
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I realize there are times when engine temperature needs to be higher. Emissions is one. When you want to make power, you lower the temperature and raise the compression ratio.

You have to look at everything. Just saying 200 is best is not true.

Also most guys can‘t get the temperature down, as exampled in this thread. So rather than start over and get control over the temperature the easy button is say 200 is good enough.

No one said "200 is best", that would be as dumb as saying "160° is best", neither are necessarily true.

Application matters. Sure, if you're tuning for maximum power on a dyno or for a 1/4 mile, you probably want your temp closer to 160°. But in that case you're going from start to WOT to shut down again. You're not doing any real driving for any length of time and you can control the conditions.

Trying to tune your street car to run at 160° is flat out stupidity. Max power for WOT on a street car that's almost never at WOT? Dumb. Instead you want the engine to run better at lower RPM's, and you want all your gaps and tolerances right with the engine properly warmed up. That way you don't have to rebuild your engine every season.

And getting hyper focused on the coolant temperature totally forgets the fact that it's just the coolant temperature, not the combustion chamber temperature, or the block temperature, or the head temperature etc. A 20° swing on the coolant temperature (assuming it isn't boiling) doesn't mean much of anything to the combustion chamber temperature. It's important for drag racing because you're tying it to the air charge temperature, but that's only because of the short *** trip you're making. Drive for longer than a 1/4 mile and the intake manifold temperature is going to go up regardless, the engine compartment temperature is going to go up, and so the air charge is going to warm up no matter what you do. Pull over and ice it down! LOL.

So you know, maybe you should tune the car for the actual conditions it will be seeing? I wouldn't tune a strip car for 200°, and I wouldn't tune a street car for 160°.
 
No one said "200 is best", that would be as dumb as saying "160° is best", neither are necessarily true.

Application matters. Sure, if you're tuning for maximum power on a dyno or for a 1/4 mile, you probably want your temp closer to 160°. But in that case you're going from start to WOT to shut down again. You're not doing any real driving for any length of time and you can control the conditions.

Trying to tune your street car to run at 160° is flat out stupidity. Max power for WOT on a street car that's almost never at WOT? Dumb. Instead you want the engine to run better at lower RPM's, and you want all your gaps and tolerances right with the engine properly warmed up. That way you don't have to rebuild your engine every season.

And getting hyper focused on the coolant temperature totally forgets the fact that it's just the coolant temperature, not the combustion chamber temperature, or the block temperature, or the head temperature etc. A 20° swing on the coolant temperature (assuming it isn't boiling) doesn't mean much of anything to the combustion chamber temperature. It's important for drag racing because you're tying it to the air charge temperature, but that's only because of the short *** trip you're making. Drive for longer than a 1/4 mile and the intake manifold temperature is going to go up regardless, the engine compartment temperature is going to go up, and so the air charge is going to warm up no matter what you do. Pull over and ice it down! LOL.

So you know, maybe you should tune the car for the actual conditions it will be seeing? I wouldn't tune a strip car for 200°, and I wouldn't tune a street car for 160°.

All my pump gas stuff is 160. All of it. They aren’t drag cars, they are street cars. Again, it’s in the build and the tune. I do not build less than 11:1 pump gas engine. It’s a waste of power. And more.
 
All my pump gas stuff is 160. All of it. They aren’t drag cars, they are street cars. Again, it’s in the build and the tune. I do not build less than 11:1 pump gas engine. It’s a waste of power. And more.
Lol. Ok buddy, if you say so.

Sounds to me like your definition of "street car" is a lot more like "weekend warrior" than actual street car.

What octane is that "pump gas", and can you get it from the gas station on the corner? Is that 11:1 with iron heads? What's the dynamic compression or cranking PSI?

How many miles a week do you put on your street cars? At what elevation? At what air temperatures?

I think your advice is entirely too specific to your build. Because the reality is that won't work for every build, and saying it will is bad advice.
 
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Lol. Ok buddy, if you say so.

Sounds to me like your definition of "street car" is a lot more like "weekend warrior" than actual street car.

What octane is that "pump gas", and can you get it from the gas station on the corner? Is that 11:1 with iron heads? What's the dynamic compression or cranking PSI?

How many miles a week do you put on your street cars? At what elevation? At what air temperatures?

I think your advice is entirely too specific to your build. Because the reality is that won't work for every build, and saying it will is bad advice.
The cranking PSI on my slant 6 is over 175 PSI and I run on pump premium with zero spark knock. It runs on 87 with no spark knock, but it runs a lot better on premium. His advice worked very well for me.
 
The cranking PSI on my slant 6 is over 175 PSI and I run on pump premium with zero spark knock. It runs on 87 with no spark knock, but it runs a lot better on premium. His advice worked very well for me.

And meanwhile my 340, which is at 9.8:1 and cranks at 180-185 psi will detonate on 91 octane at sea level in the summer if I go past 34° mechanical timing.

And that’s my point, I’m not saying his advice doesn’t work, I’m just saying it won’t work for everyone or every build. I can’t get 94 octane at a normal gas station, and I drive entirely too much to run fuel I have to buy at a track.

Saying every build should be tuned for a 160° coolant temperature is naïve.
 
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