Ford Lehman - Raw Water not pumping

[Donnie Peterson]

Hey folks. I just bought a boat with a ford lehman. I replaced all the fuel filters, but forgot to open them when I restarted the motor. The motor ran out of fuel.



I did lots of cranking, and bleed the system. Once I bleed the system it started just fine. However, the raw water pump system stopped pumping raw water.

I replaced the impeller, and it did not help. When I replaced the impeller, I had to detach it from the shaft. This allowed me to access all the screws on the cover.



When I was putting everything together, the spinning part from the motor spun freely and easily. As I put it together, I was guessing that the pump was not going to work. It did not. The spinning parts did not spin when I started the motor as they should.

Does anyone have any ideas on why this might happen and what I can consider doing to be sure that the shaft will spin to operate the pump?


Thank you!

 

[Donnie Peterson]

It is a hp63 4 cylinder if that makes a difference.

 

[Greatlaker221]

The original water pumps at least on the 120 seemed to fail. Many owners upgraded to an improved design available from American Diesel. Sounds like the same type of failure.

 

[Alisske]

Sorry to hear. I ran my 120 out of fuel when I first got her. I consider it a right of passage, lol.

That being said, the OEM pumps are two shafts that are “keyed” together. They wear and oblongate until the fail. You are lucky it did mot happen at fill throttle on a trip.

Get the replacement Johnson Pump. One piece shaft, bolts right up, no fuss.

If your not sure what pump, call Brian at american diesel. They are pricey, but best thing you could do outside of changing exhaust elbow, coolers, and injection pump oil)

Good catch though. And good luck

 

[Donnie Peterson]

Sorry to hear. I ran my 120 out of fuel when I first got her. I consider it a right of passage, lol.

That being said, the OEM pumps are two shafts that are “keyed” together. They wear and oblongate until the fail. You are lucky it did mot happen at fill throttle on a trip.

Get the replacement Johnson Pump. One piece shaft, bolts right up, no fuss.

If your not sure what pump, call Brian at american diesel. They are pricey, but best thing you could do outside of changing exhaust elbow, coolers, and injection pump oil)

Good catch though. And good luck

I am going to check that pump out. I have seen many videos of people installing it. For now, I am going to check out the shaft on the right side of the picture and see if their is a "key" that needs to be replaced.

 

[Alisske]

I am going to check that pump out. I have seen many videos of people installing it. For now, I am going to check out the shaft on the right side of the picture and see if their is a "key" that needs to be replaced.

Good idea. Not sure of the ability to replace it. But would recommend considering the new style pump. The old style works until “it doesn’t” and can be catastrophic. The Lehman’s can run forever. The one thing that can kill them in a heartbeat is a bad overheat. If you do figure out a way to replace worn shafts at a reasonable price, please share with the group.

Be well

A

 

[RT Firefly]

Greetings,
Mr. A. Your post #4. "Oblongate" GREAT word!!!

 

[Alisske]

Greetings,
Mr. A. Your post #4. "Oblongate" GREAT word!!!

???

Yeah. Spellcheck was saying it was not a word. I swore it was. Lmao

Who knows

 

[RT Firefly]

Greetings,
Mr. A. Apparently it isn't a word BUT it describes the wear pattern of the old Lehman water pump drives perfectly. Spell check has a tendency to obfuscate the Queen's English.

 

[Donnie Peterson]

Hey. So trying to take the shaft off. I am here. Several bolts have come out. I am sure I have all the bolts, but it will not come out. Any thoughts?

 

[Alisske]

Someone probably gasket sealed it on. Maybe a few knocks with a deadblow hammer If you are seasoned and “know when to stop when its not working” then may slide a putty knife or blade in between.

Or bolt the rest of the pump back on (with exception of the bolts holding it on) and maybe it will create some leverage by pulling in the pump housing

It big heavy metal stuff, not a delicate flower. You could also maybe “bump” the engine to spin the sprocket and jar it loose. But thats last resort. .

 

[Donnie Peterson]

Someone probably gasket sealed it on. Maybe a few knocks with a deadblow hammer If you are seasoned and “know when to stop when its not working” then may slide a putty knife or blade in between.

Or bolt the rest of the pump back on (with exception of the bolts holding it on) and maybe it will create some leverage by pulling in the pump housing

It big heavy metal stuff, not a delicate flower. You could also maybe “bump” the engine to spin the sprocket and jar it loose. But thats last resort. .

I have come to the conclusion that the part will not come off. It will not come off until the coupling at the end of the shaft will come off. That coupling spins freely, but will not slide off. In the first picture of this thread, I called it a "spinning part"

In that first picture, you can see an allan key hole to tighen it to the shaft. We have that pulled out right not, but it still will not come off. I do not know what that piece should look like but it appears that a part of it is broken off of it just where the threads end. (I wish I took a picture of it)





I have also come to the conclusion that the johnson pump you spoke off, will likely not fit my motor. The shaft that is sticking out from the fuel injector goes all the way through the fuel injector. (See the diagram of the fuel injector). The water pump attaches to that very same shaft.



Any thoughts on how I can get that coupling off?

 

[Alisske]

I am a littled confused and maybe steered you wring on the last post (about the fuel injection pump vs raw water pump)

On my 120 (2715e) lehman, the whole flange unbolts. (My finger is pointed to where is seperates)

The whole flange and gear comes out.

Sorry i could not be of more help

A

PS, don't bust me about the dusty engine, I have been sanding the bilge to finish epoxy coating it, lol

 

[Alisske]

This is what it looks like prior to bolting it on

 

[Donnie Peterson]

This is what it looks like prior to bolting it on

Yeah that is the one that I have seen. I do not think that will install on my motor the way it is. The pictured gears on the picture have no place to attach. The water pump appears to run directly off the same shaft as the fuel injector.

I think, I would need a new style of fuel injector to get it to install.
D

 

[Donnie Peterson]

The model number for my engine that is on the manual is: 4D220

 

[Comodave]

Call Brian at American Diesel, he is the guru on Lehmans. 804-435-3107

 

[Alisske]

Ah. Sorry about that. The issue is probably the same, but solutions will be different

Good luck with her. Winston Churchill said, “when going through hell, keep going”. Lol

It will be nice when she is all fixed up.

Be well

 

[Donnie Peterson]

Thanks. I kind of wish I tried to tighten that allan screw that goes through the coupling. The could be the issue and solved by a simply tightening. However, is seems like such a small part that could have serious issues if it fails.

 

[Bryant]

Water pump

View attachment 120457


Hey folks. I just bought a boat with a ford lehman. I replaced all the fuel filters, but forgot to open them when I restarted the motor. The motor ran out of fuel.



I did lots of cranking, and bleed the system. Once I bleed the system it started just fine. However, the raw water pump system stopped pumping raw water.

I replaced the impeller, and it did not help. When I replaced the impeller, I had to detach it from the shaft. This allowed me to access all the screws on the cover.



When I was putting everything together, the spinning part from the motor spun freely and easily. As I put it together, I was guessing that the pump was not going to work. It did not. The spinning parts did not spin when I started the motor as they should.

Does anyone have any ideas on why this might happen and what I can consider doing to be sure that the shaft will spin to operate the pump?


Thank you!

The water pump probably needs to be replaced with an upgrade. There may be broken parts of a impeller in the heat exchanger. But you also might need to flush the cooling system, clean out the heat exchangers and check or replace the elbow.