HEMI Tech - Cooling Systems

Thanks, George!

 

Josh... Last I heard, Kanter would do them. Not sure who else. Did you try them? And yes, Gary (73RR) would probably have a solution for you as well.

I have a couple that need to go out at some point as well.

 

Thanks for the plug George!

As to the pump, the 55-56 pump repair parts are getting very expensive and the special carbon seal is nearing extinction. My supplier is having some issues keeping them on the shelf.
Currently I have several rebuilt units available.

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I bought one of the Ebay $80 392 pumps. I ran it for about 300 miles with no issues then I pulled the engine for rebuild so I don't have any more experience until I put it back together. My other choice would have to get the old pump rebuilt by Egge Machine but I did not do that because the cost was about $160.

 

He did my '55 331 W/P & put on the smaller hub so a modern fan would fit.

 

The attached photos show the Meziere 55 GPM electric pump on my 392. That along with a Flex-a-Lite 3300 CFM electric fan keep the engine temp at 180* under extreme temperatures in stop and go driving. IMO way better than the OEM cooling system.

 

Why not just run the BB Chevy pump with bypass? Mine runs 180 all day driving to Louisville at 90 deg day at 85mph. or in traffic.


Ago

 

I opted to use a crank mounted ProCharger supercharger on the hemi which eliminated the crank pulley. The solution to that was an electric pump. The fact that the pump moves 55 GPM regardless of engine RPM and doesn't rob engine HP was frosting on the cake. Nothing wrong with the BB Chevy pump if it does the job.

 

Good time to run across this thread.
I had planned my cooling (or thought I did) but then had to give it all a rest.
I'm going to try and run a water pump that I think was off of a sprint car deal. It looks just like a fuel pump and I have it mounted to the timing cover. From there I've had brain freeze.
I'll take some pictures and try to post them later today, see if this can make sense to anyone else, and get me aimed again in the right direction.

 

I have to wonder....my 354's water pump spins much slower than the crank - maybe 75% or so. That is on a non-AC car. By the 60's, Mopar was spinning the water pump on a big block at crank speed for non-AC and well over crank speed - 45% over - for AC cars. Is that because the early Hemi pump doesn't need those speeds, or because they didn't know any better, or?


From the experimenting I've done....water pump speed is greatly overlooked when it comes to effective cooling.

The best setup in modern times is probably an electric pump fed by a computer controlled module that varies pump speed based on demand (temperature).

But what a lot guys overlook with electric "Misery" pumps is you can no longer run a mechanical fan, assuming the pump is mounted in the stock pump location.

 

We'll see if this attempt at loading pictures works.
Anyway, I wanted to keep this with the look of a drag inspired theme. The water pump looks like a fuel pump and is a cam driven unit mounted to the timing cover. There is an inlet and outlet on the pump.
On the front of the heads, I have a couple of 'filler necks', this was for the 'look' of an engine that would have had water only and would have been typically drained after each pass.
I have threaded adapters on the back of the heads.
Fittings on the front of the block as inlets/outlets.
Any thoughts on how this should be plumbed? What are the thought of using one inlet on the front, crossover on the back and hooking the outlet on the front of the block to the water pump and then to rad etc?
Any advice? Thoughts? Better ways?

 

Ya know, a fella could spend the better part of a college degree learning about pumping fluids, pump designs and the attendant cavitation problems...

Mixing brands with unknown compatabilities can be problematic. Proceed at your own risk.

My 2¢

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I ran into a firewall clearance issue on the ports at the back of the heads. Couldn't use them. Before you get too far down the fabrication road you might want to check that out.

 

If the electric water pump is mounted on the block you will have to use an electric pusher or puller fan on the radiator. Like a thermostatically controlled mechanical fan, most electric cooling fans can be electronically regulated by manually timing it to come on at a certain temperature.

Attached is an article that is a starting point for street rod cooling system design. http://www.crankshaftcoalition.com/wiki/Bulletproof_cooling_system

 

Has anyone ever actually had a problem with their stock early Chrysler/DeSoto/Dodge Hemi water pump not keeping their engine cool? (excluding extreme conditions/cases and super modified engines) I've never heard anything bad about the stock cooling system, except under conditions where the pump is leaking and/or in need of a rebuild. I have a Chevy pump on one of my 331's and other than it being "convenient" and light weight, I don't like it. Looks out of place and if you run the bi-pass tube between pump and cross-over (which mine has) then it's a mess of fittings that look like crap unless something clever is made for it. I'll never do it again, unless I have a good reason to do so.

 

On one of my 331s I run a BBC W/P & 392 crossover, with the heater ports plugged on the W/P, no problems.

 

No one who lives north of Texas has any right to talk about cooling! I always laugh when someone tells me they have no issues with cooling then I notice they live in Saskatchewan....

As for electric fans, I generally don't like them on larger engines, and I find they almost never package well, not on any cars I own, anyway.

In my experience most pumps need to be spun 'faster' for good low speed cooling. I wouldn't do that for a Bonneville run, but for sitting in traffic it helps a lot.

 

please never use WD40 to store engine parts!!!!! It mixes with any oil on the part and evaporates it all off;leaving bare metal to rust in a short time.Ask me how i know.

 

Ohhh boy ! I'd like to know more about these components please

 

Ohhh boy ! I'd like to know more about these components please

 

I have been fighting a heating issue with my blown 392 motor all year, anybody ever try plumbing water exit ports out the back of 392 heads to eliminate hot spots in the heads? Is this a waste of time? I dont have the room in my engine compartment but if it fixed my problem I would drill thru the firewall and plumb down thru the floor for return lines. I am not going to make this a long read with all the changes I have made to the cooling system but I have done it all except this. Last question, anybody running a .060 over motor on the street? My cooling system has 6 gallons of water with a Brassworks radiator with a spal fan and shroud etc.

 

Did you sonic check before going .060? Sounds like a lot on a 392, even w/o the blower.

 

Have you actually done temperature spot checks on the engine? Buy/rent a digital infared non-contact thermometer and see if you can find any hot spots.

A blown 392 can also have a couple of issues that others might not have, depending on how you packaged the whole mess.
How much ignition advance are you running?
How much static compression and how much overdrive?
What water pump?
Where is the t-stat?

And as George notes...060 ?

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Please define your heating "issue". High temp reading on the gauge? Boiling over? Paint burning off in spots? Detonation?

 

As asked...what water pump?

 

Because of how tight everything is under the hood I used an electric water pump. It was a 37 gpm pump and right now I am changing everything to put a BBC Stewart belt driven pump on the motor. Yes, I tried the infared guns and found no hot spots, just a slow constant temp increase to where it was reaching 225 so I shut it down. It never puked any water but was too hot for me. The temp gun confirmed my my gauge was correct. I tried thermostats, restrictor plates, nothing at all and the results were all the same, just kept getting hotter slowly. The distributer has a total of 28 degrees and I have changed it from 12 degrees at idle to locking it down to be at 28 degrees at all times. Static compression is 9 to 1 and have changed the blower speed from 6 over to 16 under, I have played with jetting to richen up the fuel to run cooler and no matter what I have done the results are all the same. Even with a large fan in front of the radiator still would get hot. I am not happy the engine builder went .060 over as the motor was a good .030 over but he has built many of them over the years and he felt thats not an issue but others say it is. I am to the point that if the water pump change does not fix it then I give up with this motor which is a blow since its all new and I have a ton of money in it. There is a video of it on u-tube called Mr Gassers 1941 Willys, it was shot right after I got it running and noticed she was getting warm. The one thing I have noticed with all other blown 392's is that they all have belt driven water pumps, its going to be a job to get it to fit but its a must do. The car is all steel with inner fenderwells and getting the motor in there was a job!

 

Where this is getting to be a build Thread maybe everything after the unanswered question about using the rear block offs should be moved to a seperate Thread from the tech Thread. What degree thermostat you using now? Some new Caddys use ones over 200. 28 deg all the time?

 

I agree, this needs to be moved to keep the Tech series cleaner. It can be referenced in the series with a link. Who is in charge of such a change??

Final question, were the holes sonic checked? My guess is that the 9:1 is too high and you are superheating some of the coolant.

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Was the block filled? And do you have an oil temp gauge? Are you sure your fan and/or radiator are up to the task? Just trying to get all the info we can to help solve the problem.

 

HRW, how about just starting a new thread with this, or jumping on to one of the existing cooling system threads? We'll find it, I promise. Meanwhile, something to think about:

Until the coolant gets hot enough to pop the cap, you don't really have an "overheating" problem. More likely, you have a heat rejection problem. Water temp is probably the most misleading indicator of how well the cooling system is working. What are we really trying to keep cool? The water, or the metal engine parts? The water is just a medium to transfer heat out of the engine hard parts. As long as we can keep it from flashing to steam, higher water temps may be an indication of the cooling system working well...

Heat gun the inlet and outlet fittings at the radiator. If you are not seeing a minimum of 50deg difference (more is better, obviously), you are either cycling the coolant too rapidly, or you simply don't have enough radiator surface to shed sufficient heat. Pumping coolant through the system faster is probably the worst thing you can do.

Think about this...heat up a burner on your kitchen stove. If you take your hand and quickly brush your fingers across the burner, you won't get burned. Now take your hand and press down flat on the burner... The only difference is contact time. The coolant needs time to get the heat out of the engine, and time in the radiator to get rid of the heat it picked up. The hotter the coolant is as it comes out of the engine (where we typically measure it) the better; AS LONG AS we can then get rid of enough of that heat in the radiator.