Yanmar 4jh3e impeller

Paul4788

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OK, this may seem like a dumb question but I'm carrying out a service on my engine, all done apart from the impeller. Because I can't find it!! The engine number is E21394. The engine was manufactured around 2001/2001 I'm not sure if there is more than one design for this engine. The engine is in a Trident Voyager 40. All the videos and diagrams I've seen for this engine show it at the front right just below the water pump with 4 screws and a plate to remove. The impeller housing looks like it protrudes from the engine. Mine looks like it has a blanking plate where I would expect to find the impeller and no housing and nothing there! Picture att.

It must have one as it merrily pumps out raw water, I'm just baffled where else to look to find it.
 

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VicS

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Do these diagrams help ?

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See the section in your owners manual describing items to be inspected every 1000 hours or 4 years

Yanmar usually say to fit the new impeller with the vanes correctly orientated to match the direction of rotation. Most people say it does not matter.
 
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davethedog

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If it is anything like the impeller housing in our previous boat, with a 4jh3e Yanmar, then the impeller is near the starter motor on the side (as in VicS reply above). A stupid design!
 

Porthandbuoy

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Changed my impeller a couple of weeks ago. It’s behind and below the alternator. I would NOT like to do it in choppy weather as I have to do it all by feel and with my left hand. The Yanmar Service kit comes with replacement bolts, which is a godsend as I always drop one or two into the bilge.
Don’t forget to replace the o-ring and slather the impeller with glycerine before you bolt on the cover plate.
 
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