Impeller help! Seized on shaft!

[Mixman1]

I have a yanmar 3JH5E. The impeller won’t come out even with an impeller puller. I soaked it overnight with PB Blaster. No luck. The impeller in there doesn’t have the threads to use the yammer puller. I am using a seadog impeller puller tool. The type with jaws that dig into the rubber hub and pull. Not even budging a little. Any advice at all?

[Hudson Force]

Can you heat the hub of the impeller with a soldering iron?

[Vingt-Knots]

Time and multiple applications are your friends when working with any penetrating ‘oil’. A good DIY penetrating solution is 50% automatic transmission fluid and 50% Acetone. The idea of heating up the hub on the actual impeller is good.

Good Luck

[Mixman1]

Originally Posted by Hudson Force

Can you heat the hub of the impeller with a soldering iron?

I haven’t resorted to that yet. The two options I see if no one on here has further advice...... cut as much of the rubber away as I can and then heat the hub of the impeller and attempt to pry it off. Or.... call someone to come out and remove it for me. Probably at great expense.
Really hoping for a solution I can handle myself.

[Mixman1]

So I pulled the whole water pump out and still couldn't remove the impeller even on a bench. I have no idea what the previous owner did, but now that it is on the bench I can see all kinds of damage around the face. Obvious prying damage from the past. I can't believe it wasn't leaking.

Ordered a whole new seawater pump assembly. Another 1 hour job turns into 2 days! lol

[Gary Mc]

When I put an overhaul kit in my Yanmar water pump there was a C clip on the shaft by the bearings. Hard to see but nothing would move until I got it off. Not sure that applies here but maybe?

[Mixman1]

Originally Posted by Gary Mc

When I put an overhaul kit in my Yanmar water pump there was a C clip on the shaft by the bearings. Hard to see but nothing would move until I got it off. Not sure that applies here but maybe?

Good to know! Thank you

[waterman46]

I'm not sure how the puller works and it might be better than my method, but if not, then what I do is use vise-grip pliars.

Clamp one on the impellor hub really tight, then clamp a second vise-grip pliars to the first one at right angles and hit that one with a hammer.


Soldering iron certainly would not provide enough heating to make a difference. A torch may heat enough to free it, but won't that fry the rubber water seal on the other end of the shaft?

[George DuBose]

I would look for that "C" clip and otherwise, remove the pump from the engine and see what seals can be removed. Then cut away the rubber part of the impeller and use heat. Maybe with the pump off the engine, one could use a hydraulic press to push the impeller out from behind the pump.

[waterman46]

Originally Posted by Mixman1

Good to know! Thank you

OP is asking about removing impellor. That C ring secures the shaft assembly (bearings, water seal, etc) into the housing. Don't need to touch it to replace impellor.

[canyonbat]

Barring just tossing it since you have a new one, I would put it face up in my vice, attach your puller, then pour boiling water into the pump and crank like crazy on the puller before the shaft has a chance to swell.

[DockDoc]

I have the same motors on my Lagoon 42. I have two replacement water pumps with the impeller already in them (sold that way). I think they were $200ish each. It may be better option to just replace the whole pump.

[Cheechako]

Check closely. Never heard of one that is frozen on the shaft, although it's possible. Are you sure there isn't some sort of clip or keeper?

[Jack C]

perhaps there is a set screw locking the impeller to the shaft. Or a pin through the shaft and impeller. Inspect with a good light.

[BlackHeron]

It is possible that the impeller was glued in place with locktite or similar due to a major shaft issue.

Now that you have a replacement I would take the old pump into a pump shop and have them rebuild/recondition it if it is not too far gone. If the shaft was screwed up enough that the previous person to work on it purposely glued the impeller on it might need a new shaft as part of the rebuild.

It is always good to have a complete spare onboard. A rebuild should be only a fraction of the cost of a new pump and well worth it to have a ready spare.