Yanmar 4JHE raw water pump drive gear removal

[James R]

I am attempting to rebuild a 4JHE water pump">raw water pump and I need some advice on removing the drive gear so I can get the large snap ring out that holds the bearing in. I have tried the available snap ring pliers and I am unable to remove the snap ring through the gear as indicated in the instructions.
It looks like I should be able to remove the drive gear with a puller, which I have and have tried without success.
Prior to continuing, is this how you remove the gear? If someone can confirm this is correct, I will apply some heat and see if I can get it to move.
Thank you
Jim

[tkeithlu]

I can't see what is preventing the gear coming off, but negative on the application of heat. The gear may be heat treated.

[tkeithlu]

OK. The gear and the shaft do not separate. They come out as a unit. You've got to try again getting your ring pliers in through the slot in the gear and grabbing the circlip. That may involve new tips for your pliers if yours are slipping. Sorry to have to say it.

If your pliers have multiple tips like mine, try using 90 degree/right angle tips. Straight tips actually are not parallel and may slip. Nasty little complication to life they are.

[flightlead404]

Channel Lock makes a kit of three sizes of circlip pliers that are ratcheting, have settings for both inside and outside clips, and have replaceable tips including straight and several offset angles.

Its fairly inexpensive and I've found it invaluable for all sorts of projects including my recent windlass-from-hell project.

[tkeithlu]

QUOTE: "including my recent windlass-from-hell project."

I am looking forward to hearing about this. Will you post it here or in the "Sailor's Confessional" forum? Photographs? Play by play? Undeleted obscenities?

[ScottRhodes13]

I've just had the pump on my 4jh2-hte apart, and can feel your pain about that circlip. I was unable to find a tool at any price that would do the job, so finally bought a pair of right angle needle nose pliers and ground down the jaws to fit the circlip.
However, you should be able to get the gear off the shaft -- it is just a press fit. Gotta warn you though that when I tried to take my shaft apart with a puller, I ended up deforming it enough that I've had to order a new one. See if you can find a mechanic with a press.

[ScottRhodes13]

One other thing to keep in mind once you get the shaft out of the pump -- if you decide to replace the bearings, note that they press off in the same direction as the drive gear. It looks like the inner bearing can be pressed off toward the impeller end of the shaft, but that's not the case.

[flightlead404]

Originally Posted by tkeithlu

QUOTE: "including my recent windlass-from-hell project."

I am looking forward to hearing about this. Will you post it here or in the "Sailor's Confessional" forum? Photographs? Play by play? Undeleted obscenities?

lol

There were plenty of obscenities as I lay in the v-berth, arms extended over my head supporting the heavy windlass as nasty old emulsified gear oil and detritus dripped into my eye

I posted a fair amount of detail on it on hunter.sailboatowners.com forum.

Should I cross post? I always try and post any resolution I find to a problem that I've asked about just in case folks find it useful on future searches.

[stormalong]

Hydraulic press. Two steel plates, one on each side of the gear and press the shaft down through the gap. Much safer from a damage point of view and much more powerful than a gear puller. There are even tapered steel plates made to get in very tight places. Use the same press to reassemble. You may have to pay someone to do it but I'll bet it is cheaper than a new gear. A good auto machine shop should have no problem doing this in about a minute.

[stormalong]

Originally Posted by ScottRhodes13

One other thing to keep in mind once you get the shaft out of the pump -- if you decide to replace the bearings, note that they press off in the same direction as the drive gear. It looks like the inner bearing can be pressed off toward the impeller end of the shaft, but that's not the case.

Anytime you disassemble a raw water pump replace all bearings and seals.

No deciding necessary. The materials are cheaper than the time to do it again a couple of years later.

[Celestialsailor]

Take it to a Yanmar service center and pay a few hundred for a rebuild and avoid buying a new pump for many hundreds of dollars

[tkeithlu]

Good morning, James.

I thought about this last night, and cannot recommend that you press the gear off the shaft rather than strugglling with the clip. Not to say that it cannot be done, but: The manufacturer did not intend you to do it that way, and supplied the slots in the gear as a work around. We don't know why. If he/she was a Honda motorcycle designer in the 1960s, it was because the press fit was too tight to be pressed without damage. Five piece crankshafts in that era were assembled by freezing the shaft, heating the counterweight in an ordinary oven, and THEN pressing the two together. At a common temperature, the shaft was bigger around than the hole in the counterweight. I'm also remembering, with fondness, the 600,000 pound test machine we played with. Yeah, it could press that. That machine is at Bucknell University now.

[James R]

Thank you to all who have replied. As the gear must be removed to replace the bearing. I will need to put it in my press. Does anyone know if the fit is a press fit, driving fit, or forced fit?

[ScottRhodes13]

James R - I can't answer your question about the type of press fit, because I don't know the difference between all those. I do know that the shop I took mine to just used a hydraulic press to remove the gear. It took a little more force than expected, but went back on easily.
As to tkeithlu's comments -- I can say that the only way to replace the inner bearing is to remove the gear, so it's difficult to believe that it's not designed to come off in a straight forward manner.

[Alita49DS]

The whole shaft assembly including the bearing is £425.49. Number 14 in this link: https://yanmarshop.com/en-GB/catalog...sea-water-pump
Or the whole pump new with the gear, not looked at HE but similar, £259 from https://www.boatpartsandspares.co.uk...3jh-5086-p.asp
How much time and effort does one want to waste? Owning a boat has always required going through the financial pain threshold!