47 Flathead Water Pump Swap Tricks?

[SoCal32]

Need to install new water pumps. One is starting to leak. I know that there's a bolt inside the water outlet. I'm looking at how short the lower hoses are and it doesn't look like it's going to be an easy job with the radiator still in place. Can it be done without much disassembly?

[mcgarrett]

The answer to your question is...yes, it can be done with radiator in place. Remove only what you need to. Take your time and take a few breaks during the job. Since you know about the bolt inside the pump inlet (where lower hose attaches), I would caution you to be extra careful removing it. If you break it off, it's a real PAIN to repair. If they both come out cleanly, put a dab of anti-seize on the threads or use stainless bolts.

[FortyNiner]

It helps to use a piece of cardboard or similar material ro protect the radiator.

[Tim Ayers]

If the hose is hard/stiff, I've found a heat gun (on fairly low temp) or boiling water poured over it helps to soften it and should allow you can bend/twist it out of the way. Sometimes you need to get a pick or something to free it from the pump. They can tend to "grow" on there after a while.

I've also found removing it from the radiator as well gets it out of the way and you are not fighting the hose and the pump.

As others mentioned, if you can't see it with how you are doing it, make sure you are squarely on the head of the inside bolt and don't round it off or break it by using too much force.

Ford had a lot of great ideas, that bolt inside the pump wasn't one of them.

If the pumps were installed that the same time, you may want to consider replacing both. If one is leaking, it's possible the other isn't far behind. You have to drain the cooling system, so it may be a good time to do both for peace of mind sake.

[ford38v8]

Yes.
Before doing anything else, firmly tap the shaft several times while at idle speed, as debris can and does at times interfere with seals. To be clear, do this is a reprimand, not crushing destructive blows. If this is successful, you will see positive results immediately.
If unsuccessful, proceed:
You will of course need to support the engine with a short section of 2x6 on your floor jack, as the pumps secondary purpose is to provide motor mounts.
Start with Removing the fan belt.
Proceed by taking a measurement of the existing hose and beyond if it could be longer.
Remove the hose clamps.
Disconnect the motor mounts.
With caution, avoiding interference with the firewall, lift the engine enough to help break the hoses free, one at a time.
Remove hose and rubber motor mount, both to be replaced with new.
Remove the pump and clean the gasket surface and the radiator neck.
Put the new rubber motor mount in place.
Being mindful of the hassle it was to clean the gasket surface, use only grease to hold the new gasket in place.
Using a single long bolt with head cut off as a temporary stud, locate the new pump correctly and install, replacing the stud last. The bolt inside the pump can be stainless to prevent rust-out in the future.
Heat the new hose in hot water.
Using silicone on the inside of the hose, slide the hose all the way onto the new pump.
Position the hose clamps onto the hose now.
With the engine still in the raised position, The hose flexible from the heat, bend it toward the radiator outlet while lowering the engine, which will easily engage the hose onto the outlet.
Complete the motor mount installation.
Adjust the hose to midpoint between pump and outlet, and tighten the hoseclamps.
Fill with water, start and warm up the engine, retighten the hose clamps.
Open your third beer and enjoy. What? You forgot the first two?

[Tim Ayers]

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Originally Posted by ford38v8

Yes.
Before doing anything else, firmly tap the shaft several times while at idle speed, as debris can and does at times interfere with seals. To be clear, do this is a reprimand, not crushing destructive blows. If this is successful, you will see positive results immediately.
If unsuccessful, proceed:
You will of course need to support the engine with a short section of 2x6 on your floor jack, as the pumps secondary purpose is to provide motor mounts.
Start with Removing the fan belt.
Proceed by taking a measurement of the existing hose and beyond if it could be longer.
Remove the hose clamps.
Disconnect the motor mounts.
With caution, avoiding interference with the firewall, lift the engine enough to help break the hoses free, one at a time.
Remove hose and rubber motor mount, both to be replaced with new.
Remove the pump and clean the gasket surface and the radiator neck.
Put the new rubber motor mount in place.
Being mindful of the hassle it was to clean the gasket surface, use only grease to hold the new gasket in place.
Using a single long bolt with head cut off as a temporary stud, locate the new pump correctly and install, replacing the stud last. The bolt inside the pump can be stainless to prevent rust-out in the future.
Heat the new hose in hot water.
Using silicone on the inside of the hose, slide the hose all the way onto the new pump.
Position the hose clamps onto the hose now.
With the engine still in the raised position, The hose flexible from the heat, bend it toward the radiator outlet while lowering the engine, which will easily engage the hose onto the outlet.
Complete the motor mount installation.
Adjust the hose to midpoint between pump and outlet, and tighten the hoseclamps.
Fill with water, start and warm up the engine, retighten the hose clamps.
Open your third beer and enjoy. What? You forgot the first two?

Great write up!

[Kurt in NJ]

Also check that the oil passages are clean if you are using original style pumps .

[SoCal32]

Thanks for the tips. Especially like the long bolt with the head cutoff to ease installation. Fingers crossed it'll go somewhat smoothly.

[L-head]

The bolt inside the water pump outlet is a 3/8 NC with a 9/16" head. Use a six point socket on it and make sure you're firmly on the head of the bolt. They can be tough to get out.

[38 coupe]

I will add one thought to the great advice above: if you are not worried about points judging consider using new silicone hose for the lower hoses. I used to dread working on the lower radiator hoses, trying to fold the hose almost in half to get both ends to line up with the pump inlet and the lower water outlet on the radiator. No longer a worry, silicone hose is flexible and easy to install. I did this a couple years ago on my dad's 46 sedan and it was amazingly easy. I have since done this on my 38 and again it was very easy compared to regular radiator hose.

[Tim Ayers]

Originally Posted by 38 coupe

I will add one thought to the great advice above: if you are not worried about points judging consider using new silicone hose for the lower hoses. I used to dread working on the lower radiator hoses, trying to fold the hose almost in half to get both ends to line up with the pump inlet and the lower water outlet on the radiator. No longer a worry, silicone hose is flexible and easy to install. I did this a couple years ago on my dad's 46 sedan and it was amazingly easy. I have since done this on my 38 and again it was very easy compared to regular radiator hose.

Interesting. Do they come in black? I've seen blue silicone hose, but haven't been in the market. I do like this idea.

[38 coupe]

Silicone hoses come in black along with all sorts of other colors, shapes, and sizes. The import tuner crowd seems to love the things, and use them for turbo setups along with other hose needs. I also used black 45 degree silicone hoses with different size ends to connect the upper hoses from the 8BA in dad's 46 to the stock radiator. I simply measured out the diameter and length needed and searched that auction site.
I do run stock upper hoses on the 38, I like the reproduction upper hoses with the Ford markings since they are easy to see and easy to install.

[Tim Ayers]

Originally Posted by 38 coupe

Silicone hoses come in black along with all sorts of other colors, shapes, and sizes. The import tuner crowd seems to love the things, and use them for turbo setups along with other hose needs. I also used black 45 degree silicone hoses with different size ends to connect the upper hoses from the 8BA in dad's 46 to the stock radiator. I simply measured out the diameter and length needed and searched that auction site.
I do run stock upper hoses on the 38, I like the reproduction upper hoses with the Ford markings since they are easy to see and easy to install.

OK, neat. Will look out for them. Seems like a great idea for the lower hoses since they are a real PITA to deal with if you don't move the radiator back and out of the way.

[ford38v8]

Originally Posted by Tim Ayers

OK, neat. Will look out for them. Seems like a great idea for the lower hoses since they are a real PITA to deal with if you don't move the radiator back and out of the way.

Tim, I know you read my post and commented great write-up, perhaps you didn't follow my instruction on lower hose install? Engine raised, warm hose bent to point toward radiator outlet, slowly lower engine to engage outlet. The weight of the engine does it all. No need to reposition the radiator. Do i need to clarify further?

[Tim Ayers]

Originally Posted by ford38v8

Tim, I know you read my post and commented great write-up, perhaps you didn't follow my instruction on lower hose install? Engine raised, warm hose bent to point toward radiator outlet, slowly lower engine to engage outlet. The weight of the engine does it all. No need to reposition the radiator. Do i need to clarify further?

Haha. Nope, I get what you are saying and I still say that your write up was excellent.

I was just thinking of my AV8 on a '32 frame that I just did this job on. The "Z" lower hoses didn't really work with your "trick". It was easier to slide the radiator forward than to fight with the hoses. On a car with fenders, I understand this may not be an option.