Crank mount raw water pump conversion question

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LoyolaCub68

LoyolaCub68

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I have a 5.8FL in a 1995 Larson 214. I would like to convert to a crank mounted water pump as the belt driven one seems expensive and hard to find. Is there any disadvantage to doing this?
 
bruceb58

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Re: Crank mount raw water pump conversion question

they are both expensive. Just bought a new belt driven one for mine.

The one I just purchased was $255
 
LoyolaCub68

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Re: Crank mount raw water pump conversion question

bruceb58 said:
they are both expensive. Just bought a new belt driven one for mine.

The one I just purchased was $255
Click to expand...

Can you tell me where you got that one from? It seems like there are some less expensive crank mounted ones, but then again there is the cost to fabricate the setup.
 
Don S

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Re: Crank mount raw water pump conversion question

The Fords never had a crank mounted pump, so you are going to be in new territory. The mount bolts are not going to be the same between the GM and Ford engines.
If you do find a pump with the correct bolt pattern, as I recall on the Fords the pulley was really deep and you will probably have to have a spacer made to move the pump out. You will also need to fabricate a support bracket to keep the pump from trying to turn, instead of just having the hoses hold it.
 
Don S

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Re: Crank mount raw water pump conversion question

Assuming you have an HU model 5.8, you would need the pump on the bottom right here Volvo Water Pumps
 
LoyolaCub68

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Re: Crank mount raw water pump conversion question

Don S said:
The Fords never had a crank mounted pump, so you are going to be in new territory. The mount bolts are not going to be the same between the GM and Ford engines.
If you do find a pump with the correct bolt pattern, as I recall on the Fords the pulley was really deep and you will probably have to have a spacer made to move the pump out. You will also need to fabricate a support bracket to keep the pump from trying to turn, instead of just having the hoses hold it.
Click to expand...

I thought I remember reading that Indmar had some engines that were a ford block that had crank mounted water pumps. I wish I had saved the photo, but I also saw someone that had twin 5.7fl's with crank mounted pumps on both of them. It seems like the change out of the impeller is much easier, also the added benefit of one less belt to break. I am concerned about the stress on the crankshaft and bearings by adding this. The price of the pump below from Bruce might make all of this moot.

bruceb58 said:
Volvo Pump 3857794
Click to expand...

So awesome, everywhere else I looked was $100 more. Thanks so much!
 
Don S

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Re: Crank mount raw water pump conversion question

I thought I remember reading that Indmar had some engines that were a ford block that had crank mounted water pumps.
Click to expand...

Couldn't say, have no experience with Indmar.

What is the difference between the two?
Click to expand...

They look different in the pictures. Pulley is larger on the one you want, probably the mounting as well.
 
LoyolaCub68

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Don S

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Re: Crank mount raw water pump conversion question

I just did some checking, and the 3858847 was used on the year earlier and the later than yours.
One thing different about boats and cars is that it's not uncommon for a boat to have a year new or older engine and drive since the boat companies buy the engine/drives from other companies (Like Volvo, Mercruiser, etc.) That's why it's always best to use engine model numbers for parts and service information.

Keep one thing in mind though with the Fords, the Volvo accessories on that engine (Ignition, fuel, couplers,exhaust) are getting hard to find and exensive. Volvo stopped using Ford in 98, and they only used them for about 3 ot 4 years after Volvo and OMC got into a joint venture. After Volvo bought out OMC completely in 98, the Fords ended and Ford got out of the marine industry itself.

Here is a service bulletin on the model numbers that may help you understand them.

View attachment P-00-0-3 How to ID VP engines NEW.pdf
 
LoyolaCub68

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Re: Crank mount raw water pump conversion question

That is great information. Thank you so much Don!
 
jerryjerry05

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Re: Crank mount raw water pump conversion question

Any disadvantages, and I'd have to say NO, there are only "advantages".
He'll need the space in front of the engine to accommodate the pump depth.

I don't recall if the 5.8 FL in 1995 used the serpentine belt or not. If so, you may need to fabricate alignment dowels for the pump flange.

IMO,ypu'll end up with a better pump system with no side load from belt tension, and easier impeller access, etc.

He can find a Johnson F5B-9 on sale occasionally for around $150, complete with new impeller.
 
LoyolaCub68

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Re: Crank mount raw water pump conversion question

Thanks Jerry. I actually purchased that exact pump. It will take some tinkering to get a bracket in place to keep the whole thing from spinning. But I think that in the end it will be much more reliable. I can keep spares on the boat and the change out of the impeller is much similar.

I may have to end up fabricating a bracket, but with the money I'm saving on the pump this shouldn't be an issue.
 
LoyolaCub68

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Re: Crank mount raw water pump conversion question

This might be a stupid question, but would there be a downside to securing the pump with a bracket to the stringer rather than the engine? I have to ask, remember I'm an automotive guy, don't crucify me.
 
Don S

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Re: Crank mount raw water pump conversion question

Engine vibration and movement.
 
LoyolaCub68

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Re: Crank mount raw water pump conversion question

photo 1.JPGphoto 2.JPGphoto 3.JPG

Just wanted to update this thread as I go about changing over the pump. I removed the bracket and belt driven raw water pump from the engine. Just got the crank driven pump and it matched up really well. I am thinking I will fabricate my own bracket that attaches to the power steering bracket, and comes down in front of the water pump pulley to secure the pump.

Won't be as easy as I had hoped to change impellers, but overall I think a better setup and the pump is a lot less money.
 
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deshet

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I understand that this is an old thread but was the support bracket required.

Also how did you figure out which side of the pump is in versus out?

Thanks
 
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