ELECTRIC WATER PUMPS

HELLO,

I HAVE AN ERA GT-40 WITH A BOSS 302 BLOCK, ALUMINUM HEADS AND A FAIRLY MILD SET-UP.

I HAVE HAD VERY ERRATIC OVERHEAT PROBLEMS AND I'M CONSIDERING INSTALLING A DAVIES-CRAIG ELECTRIC WATER PUMP.

I VERY RECENTLY INSTALLED ERA'S UPGRADED ALUMINUM RADIATOR AND COOLING FANS. IT MADE NO DIFFERENCE WHATSOEVER

I DID A FORUM SEARCH FOR D.C. AND FOUND NOTHING. DOES ANYONE HAVE EXPERIENCE WITH THEIR ELECTRIC WATER PUMPS.

ANT THOUGHTS OR SUGGESTIONS WILL BE GREATLY APPRECIATED.

Y'ALL HAVE A REALLY GREAT DAY.

BLACKJACK
(AKA JACK MOGUS)

 

[Bob Putnam]

Dave Sampson has been using a D-C pump for a couple of years. Here's a thread on Club Cobra: http://www.clubcobra.com/forums/showthread.php?s=&threadid=16328&highlight=water+pump

 

[Bill Bayard]

Blackjack,

Are you certain that this isn't due to
trapped air pockets?
It is important to have your fill neck
above the thermo housing to eliminate this problem.
How many miles are on the car? Sometimes
purging the trapped air can take a while.
I would make sure of the lack of air, before
installing an electric pump. It would be a
whole lot cheaper!
Good luck.

Bill

 

[Jim Glickenhaus]

One thing that also helps is an electric fan that cools an engine oil cooler. On my Lola I added an extra water radiator with a fan in the tail behind right side air inlet. This made a huge difference. Pulley size is important. On the street you want to overspeed water pump but not too much as it will cavitate. Electric water pumps and fans use a lot of juice and a high output alternator is very important with overspeeded pulleys as well especially at idle. Bleeding and thermostats should be checked and water wetters added to coolant help also.
Best
Jim

 

[Gary Gibbs]

On a slightly different note. I just saw that Ford Racing came out with a short nose water pump that is 4 1/4" from back to pulley flange, and thus gives 1.5" more clearance. The part number is (M-8501-S). The pulley part numbers are (M-8509-Q, and R). Thought someone might use this pump.

 

[Robert Logan]

Blackjack,

I agree with Bills coments regarding trapped air pockets.

One of the major problems with after market heads is the lack of a water passage at the rear of the engine (closest to the gearbox). Here the water boils and air / steam collects and can cause over heating problems. If this is a problem than it can be easily fixed with connections or just bleed conectors. To work out if this is the problem use a laser temperature gauge which is often used in aircraft. I am sure the average workshop at the local airadrome would help for a quick spin down the runway.

The second place to look is the radiator itself and the usual air collection on the inlet side is normal and another manual bleed point is a quick answer.

At Roaring Forties we have spent a long time designing the coolant system (note is was not called the water system) to eliminate such problems. We have incorporated an automatic bleed in the radiator , have used an extremely large aluminium core and have a by-pass from the back of the heads to infront of the thermostst. I was trapped in one of my cars in traffic for almost 2 hours the weekend of the F1 races in Melbourne. It was well into the 30's and I had the A/C on to maintain my poise and the car did not over heat ONCE and the back of my shirt was dry as a bone !!!!!!

This is one of the most frustating things that happens all to often with kit cars but is fixable.

As regards to the Craig Davis pumps made here in Melbourne , they are not as good as advertised. They require a large current to drive them and therefore absorb horse power and the fitting of them requires special fabrication. We have used STANDARD Ford pumps as this is a " can go wrong part " and I wanted the service to be EASY.

Good luck and if I can be of any help please contact me through the normal channels.

Best wishes,

Robert

 

[Jim Rosenthal]

This topic came up in a previous forum discussion. I think it was Frank Catt that mentioned swirl pots, which are a place int eh cooling system where air bubbles can coalesce and then get removed from circulation. Maybe one of those would help. I also concur with using a IR or laser thermometer to figure out where the hot spots are; I have had the problem of localized air pockets int he cooling system on marine engines and you have to bleed the air out. It is a pain.
Somewhere in the GT40 literature is a photo of competition cars with the rear ends jacked up about three feet, to bleed the cooling system, so evidently this is not a new problem. Does anyone know of a way to pressuure-bleed the system with the engine off?
As Robert points out, if the system is properly bled of air and the circulator pump of adequate size, it should function fine. I don't think the problem is one of pump size; I think you have trapped air that boils, forms steam, and airlocks the system so that water can't flow.

 

[Ian K]

How does the D-C pump compare with
the one available from Demon Tweeks?

Also, I agree with Jim about an oil
cooler.

Ian

 

[Jim Glickenhaus]

Dry sumps also help cooling. My MK-IV holds 5 gallons of oil that runs through a cooler with a fan. There is a clear circle in the body that looks into a site glass in the sump so you can check the level without opening the tail.
Best
Jim

 

[Frank Catt]

When I first got into 40s engineering, the biggest problem for owners was cooling systems and engine problems related to heat. The initial look quickly found the trapped air problem at the rear of the block, and I know use a system that constantly bleeds air from the back of the cylinder heads to the expansion tank by two -3 braided pipes. This system works extremly effectively, and we no longer have differential temperatures across the block. More recently I have also developed the coolant swirl pot idea, which is now running on several cars, and this has also vastly improved the cooling systems, and eliminates the need for any air bleeding once the system is full. I do not use electric water pumps, and usually fit just a Eidelbrock aluminium standard pump. Call me if you still have problems. Frank

 

[Bill Bayard]

If you don't have an aerodrome nearby, any decent diesel shop should have a pyrometer,
which is used to detect non-firing cylinders in diesel engines. A pyrometer will find your hot spots easily.
You should get a clue as to what the overheating problem is by the location of the hotspots.

Bill

 

Jack,
I have a BOSS 302 in my car that is working very well. There are a few things that you need to check to insure proper cooling with your BOSS. First, did your (or you) machine shop drill the extra holes in the heads to match up with cooling passages in the BOSS 302 block? This must be done. The BOSS is different from the other 302's. Check in the back of the Ford SVO book - the modification is described in enough detail. Next, Frank is correct. You need a swirl pot. This is an air trap that collects the water from the top of the block, (intake manifold) before it goes to the radiator in the front of the car. In the top of the "pot" is a bleed line that you will connect to the pressureized water header tank in your engine compartment(nothing to do with the exhaust - some people refer to this as the puke tank). This is a pressureized system. You will also need to connect a bleed line from the top of your radiator to the header tank. The header tank is mounted to be the highest component in your entire cooling system. Trapped air bubbles into the top of the tank, water is pushed or sucked out the bottom.
Regards
Greg

 

[Jim Glickenhaus]

The 427 in my MK-IV is plumbed this way as
well.
Jim

 

[Robert Logan]

I totally agree with Greg and the swirlpot but they are not mandatory with road cars.

We used them and found them very useful but our new road system does not use one and we are still fine.

The swirl pot has a tangental entry port and the water (and air) enters the pot at speed and the heavier water particles stick to the sides while the lighter air migrate to the center, thus seperating them. We used them a lot in the Royal Navy on steam ships to seperate water particles from steam (water can cause a little problem when it strikes turbine impellors). The equipment we used were called "cyclone seperators" and used the same principles of operation.

An important part of the design of any cooling system is what is called "ullage".
This is a term used in the wine making process most frequently but has its place in our cooling systems. It is the volume of air in the system to allow for expansion. This volume is dependant on the systems operating pressure and there must be enough ullage to not allow the air from the pot to enter any other part of the system during the cooling down cycle.

Like every part of every car, due consideration must be made for all factors and this is the reason that I have used highly experienced RACE engineers during the design process. These engineers are having to deal on a daily basis with engines and their associated systems that are operating at their critical load position. Ross Holder has been pivitol in the design of our cars and he allows me to be in charge of astetics only (joke).

Goo luck and Best wishes,

Robert

 

WOW - WHAT A WEALTH OF INFORMATION.

THANKS VERY MUCH FOR ALL THE SUGGESTIONS. I WILL CAREFULY DIGEST AS MUCH AS I CAN AND WILL PROBABLY BE ASKING FOR SOME CLARIFICATION AS SOME OF THE CONCEPTS ARE COMPLETELY NEW TO ME.

JIM & FRANK: WHERE CAN I OBTAIN A "SWIRL POT" OR "CYCLONE SEPARATORS"???

GREG: WHERE CAN I GET A COPY OF THE FORD SVO BOOK THAT YOU FERERRED TO???

THANKS AGAIN FOR ALL THE GREAT INFO. THE HELP IS MUCH APPRECIATED.

Y'ALL HAVE A REALLY GREAT DAY,

BLACKJACK (AKA JACK MOGUS)