Yanmar pump impellor

[Grehan]

Last few seasons, the yard engineers did it. This year I thought I'd do my own winterising including the engine.
Reasonable success, except for the removing/(later on renewing) the seawater pump impellor.

My engine's a Yanmar 3HM35F and I have excellent access to the one side of it . . but not the water pump side. [of course] [another victory for Sod's Law] Reaching under the forward end of the engine, I can touch it. I think I can touch the six screws that hold the cover on. I think I might be able to unscrew the screws and remove the cover, presumably then remove the impellor (although maybe not, if it's fairly stiff?). But even assuming this, I'm very worried about being able to put the whole thing back together again properly, the right way round, blind and at the limits of my reach.

Anyone know this engine well? Is there a knack, trick or wrinkle to it?
(I'm currently thinking of getting the yard to do it, but based on my new-found first-hand knowledge I can't even see how they'd do it!)

Do you? . . . Mr Jones

 

[Guest]

i have a 2gm, but i think the layout is the same. dont try to remove the impellor from the pump in situ. much the best way is to slacken off the drive belt, remove the whole pump assembly and then remove the pump cover, with the pump somewhere where you wont looose the screws when you drop them.

i carry a complete spare pump in case i have impellor probs at sea. if your not prepared to do that, the look at a speedseal.

all the above assumes that it is the sea water pump you are referring to, not the cooling water pump,.

 

[vyv_cox]

I do the same as Howard. Take the pump off first, it's quicker in the long run. No need to disconnect the hoses, they are long enough to allow the pump body to be turned 180 degrees.

 

[charles_reed]

Take the pump off - there are only two bolts holding it in position and the hoses are usually long enough to get it into a position where you don't have to be a 7-fingered, double jointed dwarf to deal with it.

These boatbuilders continue to fit engines in a thoroughly incompetent manner.

 

[jimi]

I do the same but also have fitted a speedseal in case of having to remove and change whilst at sea. Please note that the impellor for the 3gM is dependant an the age of the engine, the newer ones use a different impeller from the older models.

 

[steffen]

Speedseal??

I too have a Yanmar 3GM, so i am faced with the same problem.
Can you tell me what a speedseal is. It sound like i have to add it to my standard equipment.

Happy sailing, Steffen

 

[salamicollie]

Re: Speedseal??

See
http://www.speedseal.com

Have one on my 2GM, works perfectly and having had to use it in anger its a damn sight easier than trying to undo the all those screws.

 

[steffen]

Tks n.m.

n.m.

 

[Grehan]

Thanks

Thanks guys.
Very much appreciated.
It's one thing encountering this problem out of the water, another thing if it had happened in more urgent circumstances.

I might also add that the Yanmar manual (which as you might imagine I read every word of in my search for an answer) says absolutely zilch about how to get to the impellor, remove, refit, etc.

 

[dickh]

Re: Speedseal??

I too can recommend the Speed seal - you can change the impellor in under a minute - but my pump is accessible from the front. I also keep a pair of cheap long nose pliers hanging nearby together with a spare impellor for instant replacement.

dickh
I'd rather be sailing... /forums/images/icons/smile.gif

 

[Eudorajab]

Take the pump off its easy