Yanmar 2qm20 water seal and other problems

[John Teale]

hi all.

I have water coming from a small hole just behind my impeller housing. Looking at the manual it looks like the water seal on the drive shaft of the impeller has gone.

Has anyone changed this? Any tips?

Also my alternator seems weak. Putting a multimeter on both batteries today showed that there was only 12.5 volts on both my batteries with the engine running. They must have been getting a charge some how as I have used chart plotter and autopilot for hours. Maybe it being old is this just normal?

Thanks

John.

 

[JVL]

Your waterpump needs a rebuild seals and bearing from iircc simply bearings I rebuilt one last year £25 for two complete sets in stainless (one for now and a spare set) check the shaft is not scored, google around for instructions I removed the circlips and used a socket as adrift it's a couple of hours work. Alternator doesn't sound happy have you checked it's output running ie at the batt + terminal if it's low whip it off take it to a auto electric place get them to check/rebuil/swap should not be a fortune.

John

 

[John Teale]

Hi john.

Thanks for all the info.

Did you get the 2 oil seals from simply bearings too? I am hoping the least I can order from yanmar the cheaper it will be.

Thanks.

John.

 

[JVL]

Yes oil seals are stainless, just make sure the shaft is not scored new yanmar one is £75 and the don't have the decency to don a mask !

John

(the £25 was for two sets of bearings and seals)

 

[JVL]

If your alternator is terminal I can recommend "the starter and alternator co" I replaced my yanmar / hitachi with a straight fit uprated 105 amp puts out 14.58v hot run it on a gates belt iircc £155 no connection other than happy customer.

John

 

[30boat]

John

(the £25 was for two sets of bearings and seals)

That looks expensive to me.Bearings should be about 2 or 3 euros around here,less for the seals.Just buy normal seals and reuse the old springs.At a pinch "o" rings can be used as springs as long as the tension is about right.

 

[John Teale]

Just a quick question.

I am thinking about just getting a new alternator as they are not expensive, but can I just connect it up? The one on the engine now looks original and I wonder if I need to fit a voltage regulator or the likes.

Thanks

John

 

[JVL]

Assuming your alternator is original hitachi either a 55 or 35 amp ( lr155 or lr135)then the uprated one from the starter and alternator co A1632 I suggested in my previous post is a straight swap though you have to alter the lamp wire ( instructions supplied takes a minute)
The regulator is rated at 14.58 v hot, so no real need for any external regulators/ boosters.

John