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more · 11-01-2022, 03:59

why you playing for 100$-150$ savings.
https://bigblueoceanmarine.com/jpr-y...1-10-13328-03/

Celestialsailor · 11-01-2022, 09:01

Quote:

Originally Posted by Alita49DS

How much time and effort does one want to waste? Owning a boat has always required going through the financial pain threshold!

Quote:

Originally Posted by more

why you playing for 100$-150$ savings.
https://bigblueoceanmarine.com/jpr-y...1-10-13328-03/

This is the point I was trying to make. Unless you know exactly how to rebuild the pump, you stand a good chance of messing something up. As I remember getting to the pump on my 4JH was no cake walk.

**hpeer** · 11-01-2022, 09:16

Our 4JH4 has 2,600 hours. I started to see some small leakage. As I was fully occupied with a non-boat project I had a local marine shop replace it AND replace my engine mounts at the same time.

From this thread that sounds like a good decision.

I was struggling with learning to restore 130 year old plaster.

James R · 11-01-2022, 09:28

Celestialsailor,

Removing the pump was actual easy two hoses and 4 bolts is all. As far as rebuilding the pump, I have not rebuilt this pump but have several other pumps.

Mostly looking for information on removing the drive gear as it needs to come off to replace the bearing.

From the responses I have, it needs to be pressed to remove and replace. I was hoping it could be removed with a puller so it could be rebuilt on the boat if needed.
I may still try heating the gear and cooling the shaft to see if it can be done with a puller. I will let everyone know how it turns out.

Jim

Celestialsailor · 11-01-2022, 16:18

Quote:

Originally Posted by James R

Celestialsailor,

Removing the pump was actual easy two hoses and 4 bolts is all. As far as rebuilding the pump, I have not rebuilt this pump but have several other pumps.

Mostly looking for information on removing the drive gear as it needs to come off to replace the bearing.

From the responses I have, it needs to be pressed to remove and replace. I was hoping it could be removed with a puller so it could be rebuilt on the boat if needed.
I may still try heating the gear and cooling the shaft to see if it can be done with a puller. I will let everyone know how it turns out.

Jim

Hope it all works out for you. You might want to take it to an Automotive Machine Shop to get it pressed out. Cooling steel does almost nothing in reducing size. On a small shaft like that, maybe .0001" (1 tenth of 1 thousands of an inch). Heating the gear may expand it .0005" (half a thousands) but I imagine it would still have to be pressed off. I know this because I am a Toolmaker of 40+ years.

**hpeer** · 11-01-2022, 16:31

Interesting about removal. MY pump requires the engine mount to come off. Ditto the fuel injection pump.

James R · 14-01-2022, 06:56

Quote:

Originally Posted by hpeer

Interesting about removal. MY pump requires the engine mount to come off. Ditto the fuel injection pump.

Hpeer,
Your motor must have a different configuration. Mine is on the other side from the injection pump under the alternator. It was simple to remove and replace.

Now the rebuild was a little more difficult. I would say it would not be a repair I would like to do underway. I am glad this is my spare pump.

It took about a1.5 hours to do in my shop on land.

Notable in the rebuild:
To remove the gear to replace the bearing behind the gear requires a press
(Not an item I have on my boat.)
If you only need to replace seals the gear does not need to be removed.
The snap ring is difficult to remove through the slots in the gear. You will need a very good snap ring pliers.
Once the snap ring is out the shaft and bear can be removed. It is easily driven out with a soft drift punch (aluminum in my case) and hammer
Seal can be removed with a punch once the shaft is out, being careful not damage the seal bores.

Replace in the seals requires several seal drivers. I used a large socket for the oil seal. But had to fabricate a driver for the mechanical seal out of a pcv pipe coupler.

I would say the job is doable if you have the tools and bit of experience with replace seals and remove snap rings and if replacing bearings have access to a press or a shop that has a press to remove and replace the gear. It is unfortunate, that Yanmar used a pump that so difficult to rebuild.

Thanks for all that provided comments.

Jim

Jim

**hpeer** · 14-01-2022, 08:38

Same config:
Raw water port front
Starter port aft
Injection pump sbd front

What may be different are the engine mounts? Don’t know. But the injector pump has one bolt behind a engine mount. And another boot that requires 2 extensions and 2 universal joints, and one bolt is clear.

The water has one bolt directly behind an engine mount.

Or maybe there is a trick I don’t know.

And hopefully will never need to learn!

ScottRhodes13 · 12-02-2022, 11:33

Thought I'd better post a warning for anyone who wants to rebuild a pump using the recommendations that I and others have posted on this thread - - about 10 engine hours after installing my rebuilt pump, it failed. The gear that I'd pressed on and off the shaft is now spinning freely on the shaft. Clearly it is more than a simple press fit.

chrisr · 12-02-2022, 12:04

if anybody is looking for a genuine yanmar RWP for a 4JH pm me. i have one - brand new / unused / still in original factory packaging. thought i needed to replace RWP but found problem was elsewhere

cheers,

**hpeer** · 12-02-2022, 12:15

Quote:

Originally Posted by ScottRhodes13

Thought I'd better post a warning for anyone who wants to rebuild a pump using the recommendations that I and others have posted on this thread - - about 10 engine hours after installing my rebuilt pump, it failed. The gear that I'd pressed on and off the shaft is now spinning freely on the shaft. Clearly it is more than a simple press fit.

Ouch, sorry to hear thatZ. Thanks for following up.

SRizzo · 02-04-2023, 17:26

When taking this water pump off of the engine, I know there is a gasket, but don't know what that gasket is holding in. I imagine that there is some kind of lubricant in there to prevent excessive wear on the gears. Is this engine oil, long life grease, or something else?