Water Pump Pulley Sizes for Early Ford Engines 1

[AllorNothing]

Anyone have a listing of ford part numbers vs. water pump pulley diameter / offset / bolt pattern?

I want to overdrive the waterpump on my 71 429 to alleviate some slow idle cooling deficiencies.

Thanks

 

[OP800]

The MARCH company has a good selection for this engine (429-460) and even conversions to serpentine belt drives.
I would go to their site and e-mail them you application.
If you can locate a larger crank pulley, it will run everything a bit faster, otherwise you get into selecting other pully sizes to reduce the other acc drive speeds.
All most everyone goes the other direction trying to get more engine power back and gets into charge and heating problems.
Good luck.

 

[MikeHalloran]

Don't bother changing the pulleys; they were right, once.

Replace the radiator before you do anything else.



Mike Halloran
Pembroke Pines, FL, USA

 

[AllorNothing]

In general terms I would agree with the pulley suggestion, however there is more to the story. Engine displacement has increased to 514 CID, there is a automatic transmission cooler tempering the air before the radiator, and the waterpump is a cast aluminum edelbrock unit that seems to be lacking on flow in the lower rpm range. Edelbrock is unable to supply a pump curve even though their website boasts a "water pump dyno". If I set the idle up it stays cool. At 500 rpm it heats up. Radiator is in peak condition.

 

[MikeHalloran]

Ah. Speed parts. In that case, my second choice would be downsizing the w/p pulley a bit. My first choice would be a genuine Ford pump.



Mike Halloran
Pembroke Pines, FL, USA

 

[Fabrico]

Ford Racing does make a performance pump for the 429 that claims more flow at lower RPM. March lists an overdriven W/Pump set up.

 

[firefrog]

Hi allornothing
Before you spend megabuck$, here's a few cheapo tricks that might work. If the impellor doesn't already have one, you can install a circular sheet metal disk at the back of it (spot weld it, no rivets). Also try to move the impeller back or forward on the shaft to optimize the flow at that lower rpm. Again, make sure the damn thing can't come loose. Good luck.

 

[AllorNothing]

Interestingly enough, the stock pump with the cast impeller did seem to perform more reliably at low rpm. I have some suspicions that the edelbrock pump is made for those in mind that idle their overcammed engines at 1500 rpm.

To enhance the story some more, the motor is in my 1971 ford LTD and I am using it tow a 30' 6500# holiday trailer. Ironically as long as I am moving or on high idle everthing is fine from a cooling aspect. Only when I am jockeying around in a camp spot is the overheating occuring. This is what leads me to believe that fancy pump I just bought is not pumping adequatley at low rpm. I think I will hunt down a pulley that is smaller for the water pump, therefore increasing the base rpm of the pump and bladed fan, leave the crank pulley alone, since it runs the ps pump too. I will add a clutch fan if I can hunt one down. I may also switch from the 1971 steel fan to a 1976 steel flex fan of a newer LTD. The thought on the clutch fan is to return extra HP at highway speed / cool conditions. The clutch should lock up during any hot operation provided water flow is happening and the rad is hot.

Any clever folks out there know how to make a RTD work on a DVM with a minimum of parts? i.e. an op amp / resister network? I haven't gotten to installing a proper water temp gauge yet. (yeah yeah I know, I have just been busy . . .)

I would love to finish edelbrocks work by installing a flow meter in the radiator hose, any smart ideas to measure flow in a rad hose for cheap. A 1.5 inch magmeter would be sweet but $3K is a little rich.

a household water meter might work, but I don't have one and am not too sure how well it would deal with 100°C coolant.

 

[patprimmer]

Running hot at low speed is more likely insufficient air flow rather than insufficient water flow.

Do not reduce the air pumping capacity of the fan. In fact, increase it if you can.

Regards

eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

 

[Fabrico]

Yes, why all the focus on water flow?

Electronically measure water flow rate but no temperature gauge...

Looks like an example of doing first things last.

 

[Tmoose]

got a fan shroud?

 

[AllorNothing]

Fan shroud - yes

Temperature gauge tell you that you have a problem, a flow meter may tell you why.

Guess it's just the P.Eng. in me.

I agree, fan speed / air flow is also important, hence the smaller pulley that started this whole thread.

Im am considering the clutch fan, since I do not have a problem above idle. Clutch fan is temperature dependant, not rpm dependant.

 

[patprimmer]

I was thinking bigger fan rather than faster fan.

Increasing pump speed just might induce cavitation at higher speeds than tested for in original application.

Regards

eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

 

[GregLocock]

Run by a scrapyard and pick up an electric cooling fan and shroud from say a VW Rabbit. They are nicely engineered and shouldn't cost more than 20 bucks.

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[carnage1]

If you dont mind loosing a few horse I suggest the stock ford rigid five blade fan off the 70's era trucks. they have about the same pitch as a flex fan but dont flex. I have used these fans to effectively cool a number of ford cars that have had problems overheating in cruises. Also im not sure you lose all 3-5 HP that the fan chews up, I think you get some of it back in thrust. You will see what I mean when you intall it.

 

[Fabrico]

Fan thrust brings up a point with big blocks. Big engines fill the engine compartment much more thoroughly. More than once, I have helped heating problems by modifying fender wells and moving hoses to imporve exit air flow.

 

[AllorNothing]

Seriously, back to the very fist post, I want to try a smaller water pump pulley to increase the fan speed relative to the crank. The present pully is 6 1/2 inches and I know there are smaller stock ones around. The older mustangs have about a 5 inch unit. The present fan is a 6 blade solid steel unit. It does move a ton of air, I think it and the pump is just running a little slow at idle.

As for engine compartment space, it is pretty plentiful, this is a full size car.

I still really have my suspicions on the water pumps ability to pump at low rpm.

Edelbrock says high pump rpm is not a problem, claiming that I can spin it as fast as I want within the constraints of the mechanical pulley ratios.

I would like to track down a IR thermometer to compare block temp to radiator core temp and see if everything is hot. This would go a long way to understand where the cooling breakdown is happening.

i.e. if the rad is cool and the engine hot, there is probably not enough coolant flow;

if the rad is hot and the engine hot there is probably not enough air flow.

Differential temperature would tell a lot more than just engine temperature.

 

[AllorNothing]

For the record, the present fan is 6 blade solid steel and the top pulley is 6.5 inches the lower pulley is 7 inches

 

[Fabrico]

Is the 500 RPM idle in gear or in neutral?

Amazing, you are towing a 30 foot long trailer that weighs 6,500 pounds with a car, and you don't even think you should have an engine temperature gauge.

"if the rad is cool and the engine hot, there is probably not enough coolant flow;"

"if the rad is hot and the engine hot there is probably not enough air flow."

if the engine starts smoking or knocking going up a hill, it's probably ruined.

 

[Tmoose]

I've never had a new radiator that had hot and cold (blocked) sections, but I've had a few used ones that sure did.