Yanmar Impeller Help!

[Wotname]

Originally Posted by noelex 77

The impeller tool is probably the same for the 54hp, 75hp and 110hp as these are basically the same engine. Yanmar engines are popular. Most larger Jeanneaus for example seem to have one of these fitted.

Is there a boat you could borrow the tool from? They are included with the engine so most boats with this engine will have one on board.

Keep in mind the tool only works for genuine Yanmar impellers. The Johnson impellers that are otherwise the same part do not have the thread.

AFAIK, the Johnson impeller PN 1027B-1 is not threaded however it has been largely replaced by PN 1027-BT which is threaded. The photo in the OP certainly looks threaded and is a Johnson 1027 BT impeller.

[noelex 77]

Originally Posted by Wotname

AFAIK, the Johnson impeller PN 1027B-1 is not threaded however it has been largely replaced by PN 1027-BT which is threaded. The photo in the OP certainly looks threaded and is a Johnson 1027 BT impeller.

Thanks, that is good to know.

A lot of stockists won't keep the genuine Yanmar impeller because most customers want the cheapest option, so the genuine ones are a bit hard to find. None of the non genuine impellers I have purchased so far have been threaded, but it sounds like that has changed.

I have good access so removing the unthreaded impellers is no big deal, but it is a bit slower.

[Dockhead]

Originally Posted by CarlF

Yanmar makes a clever revoval tool that screws into those threads. Is there a chance it's unnoticed at the bottom of your spares kit?

129671-92110 YANMAR IMPELLER BOLT

Here's a guy who made his own but that still won't help you in a secluded anchorage

Yanmar 4JH4AE Tips

Yes -- you must have this tool, Ken. It's very cheap and essential. I have never been able to get my impeller out any other way.

Query why your impeller went bad so fast -- these are rated for 1000 hours and I've never had a bad one. I replace them every other year (about 500 hours) and they always come out looking like new.

[Kenomac]

Already thought of the borrowing possiblity. But we are now in the shipyard waiting for the engine to cool down. With three spare impellers in my drawer, believe me, this is not how I planned it. Who would have thought I be stopped by the lack of a tool.

I had the option an hour ago in the cove of cutting off each of the old impeller fins and would probably have been able to change out the impeller, BUT... if it didn't go as planned, we would have been stuck with no electricity and no propulsion and batteries at 40%. So... holding a wrong sized generator impeller I purchased this morning in my hand, I decided the wisest course of action was to return to the shipyard and exchange the 40 euro part for one hour of engineer labor and get this thing fixed... Then get on with the voyage.

[Kenomac]

Originally Posted by Dockhead

Yes -- you must have this tool, Ken. It's very cheap and essential. I have never been able to get my impeller out any other way.

Query why your impeller went bad so fast -- these are rated for 1000 hours and I've never had a bad one. I replace them every other year (about 500 hours) and they always come out looking like new.

I read the 1000 hour replacement recommendation just a month ago in the maintenance book and decided not to replace. Mine has been in just over two years with around 250 hours on the motor, so..... the Yanmar recommendation is B.S.

From now on this $30 part will get replaced along with the generator impeller at the beginning of each season. Yes... These are Westerbeke and Yanmar OEM parts.

[Kenomac]

The Johnson part is the Yanmar OEM part. It was in the Yanmar OEM plastic wrap and does have the threads.

[Dockhead]

Originally Posted by Kenomac

I read the 1000 hour replacement recommendation just a month ago in the maintenance book and decided not to replace. Mine has been in just over two years with around 250 hours on the motor, so..... the Yanmar recommendation is B.S.

From now on this $30 part will get replaced along with the generator impeller at the beginning of each season. Yes... These are Westerbeke and Yanmar OEM parts.

Ken, my experience with the Yanmar impellers is that they are, for some reason, far more durable than others I've had in my life, and I don't think 1000 hours is far off the mark.

One tip I can give you, however, is to install a Speedseal plate, the one wth the teflon part, in place of the factory on. The teflon makes a huge diference in wear of the edges, and the impeller will better tolerate running dry. The thumb screws make it far easier to get the plate off in the awkward position Yanmar gave us.

I keep the special tool and a spare impeller and an extra top plate screw in a bag zip tied near the salt water pump -- so I don't have to look for it in case of a emergency.

Every other year replacement does fine in our application, but YMMV. Obviously changing it every year won't hurt anything at all.

[noelex 77]

Originally Posted by Dockhead

I replace them every other year (about 500 hours) and they always come out looking like new.

I like to replace ours yearly despite very few hours. My theory that it is cheap insurance.

I agree most times it is perfect, but I did have one occasion with a cracked blade after only 12 months. I have no idea why this particular impeller failed so prematurely. On all subsequent changes the impeller has been like new.

Defective, or maybe I picked up a plastic bag at one stage and it briefly ran dry? There was no episodes of abnormal temperature or any indication of blocked raw water supply, but that is all I can think of.

[Kenomac]

Originally Posted by Dockhead

Ken, my experience with the Yanmar impellers is that they are, for some reason, far more durable than others I've had in my life, and I don't think 1000 hours is far off the mark.

One tip I can give you, however, is to install a Speedseal plate, the one wth the teflon part, in place of the factory on. The teflon makes a huge diference in wear of the edges, and the impeller will better tolerate running dry. The thumb screws make it far easier to get the plate off in the awkward position Yanmar gave us.

I keep the special tool and a spare impeller and an extra top plate screw in a bag zip tied near the salt water pump -- so I don't have to look for it in case of a emergency.

Every other year replacement does fine in our application, but YMMV. Obviously changing it every year won't hurt anything at all.

Chances are, I'm just looking at the badly worn edges and the fins are fine. But if you just had your Westerbeke impeller blow up that was changed on the same day two years ago, and you opened up the Yanmar housing and saw what I saw on Saturday, would you set off on a 100 mile crossing without a generator and without changing at least one of the two impellers?

[Kenomac]

Here's what's left of the Westerbeke OEM Johnson 810 impeller that was changed on the same day as the Yanmar Johnson OEM impeller.

[Sailmonkey]

Originally Posted by Guy

With a old worn out cam that might happen but with a new cam it can't happen. When was the last time you changed one of those?

Try turning your pump backwards for a bit like the engine was just shut down and rocked on a compression stroke and see what happens.
The pump on my engine is new, and the vanes will reverse.


Sent from my iPhone using Cruisers Sailing Forum

[Charlie]

Good stuff Ken. €40 well spent. Nice folk at that yard. Perhaps we will see you in Le Grazie.

[noelex 77]

Originally Posted by Kenomac

Here's what's left of the Westerbeke OEM Johnson 810 impeller that was changed on the same day as the Yanmar Johnson OEM impeller.

Try matching up the bits like a jigsaw. Any that are missing will have gone downstream with a risk of partially blocking the heat exchanger.

[Kenomac]

Originally Posted by noelex 77

Try matching up the bits like a jigsaw. Any that are missing will have gone downstream with a risk of partially blocking the heat exchanger.

Did that two days ago. All bits accounted for. Thanks

[Kenomac]

Originally Posted by Charlie

Good stuff Ken. €40 well spent. Nice folk at that yard. Perhaps we will see you in Le Grazie.

Total cost of repair 23 euros. Excellent yard, very nice staff. They got us in immediately, let the engine cool for two hours at the repair dock, 20 minutes of repair time.

Here's a picture of the old impeller, glad we changed it. Several fins half missing, with most cracked and ready to let go. From now on, this will be changed annually, NOT after 1000 hours like the service manual recommends.

Off to Cinque Terre in the morning.