Johnson Water Pump on Yanmar Identification

ctva

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I have a leaky raw water Johnson pump on my Yanmar 3GM30F which uses an F4 09-810B-1 impeller. The leak appears to be coming from the shaft seal at the back (not the impeller opening face plate side).

First question is, can I use a service rebuild kit to sort it and if so how can I identify the model number of the pump? This kit appears to be what I'm after but I need to be sure of the pump model http://www.ebay.co.uk/itm/Johnson-0...831363?hash=item1c60f630c3:g:4i4AAOSwpzdWtAqL .

Secondly, if I am better to replace it and buy a new pump, can anyone advise on a good supplier in the UK?

From what I have read on this and other forums, it appears to be a tricky job to get right. I have the full service manual so can see what is needed but any help of pointer would be appreciated.

Many thanks for your time.
 
There are two water pumps that could be fitted to the Yanmar 3GM30F, in fact the different water pump is I believe the only difference between the European, E-version engines and those supplied elsewhere. If you're buying parts, you need to know which one you have as the impellers at least are not interchangeable, the E-engine impellers being secured via a threaded transverse pin, the remainder having a key-way on the side.

If you have the E-engine, I can let you know the generic bearing & seal reference numbers that you'll need for a rebuild - the parts are better quality than provided in a rebuild kit and less than £20 for the lot.
If you choose to replace the pump, you'll soon discover that the 'standard' pump is about 50% more expensive than that fitted to the E-version - no idea why? - but the pumps in their entirety are directly interchangeable, so buy you can buy/fit the cheaper one irrespective of which is currently fitted..
 
There are two water pumps that could be fitted to the Yanmar 3GM30F, in fact the different water pump is I believe the only difference between the European, E-version engines and those supplied elsewhere. If you're buying parts, you need to know which one you have as the impellers at least are not interchangeable, the E-engine impellers being secured via a threaded transverse pin, the remainder having a key-way on the side.

If you have the E-engine, I can let you know the generic bearing & seal reference numbers that you'll need for a rebuild - the parts are better quality than provided in a rebuild kit and less than £20 for the lot.
If you choose to replace the pump, you'll soon discover that the 'standard' pump is about 50% more expensive than that fitted to the E-version - no idea why? - but the pumps in their entirety are directly interchangeable, so buy you can buy/fit the cheaper one irrespective of which is currently fitted..
Mine is an E version with the transverse pin.

I'm in two minds as to whether to get a replacement pump and repair the existing one as a spare or just do the repair and refit. Thanks.
 
Mine is an E version with the transverse pin.

I'm in two minds as to whether to get a replacement pump and repair the existing one as a spare or just do the repair and refit. Thanks.

OK, if you want to rebuild, the parts needed are:
Bigger bearing – S62012RS
Smaller Bearing – S60012RS
Seal – SEAL2-VITON 12-24-7 R23 (double lipped)
O-Ring -11 x 2.4mm – 24N0116

These bearings are all stainless steel, whilst those you'll get in a Yanmar/Johnson Kit are not, which is why they corrode/die immediately the seal starts to leak and always need replacing along with the seal - good business.
The 'standard' seal is single lipped, but I chose the twin lipped version on the basis that two seal faces are better than one; similarly, you don't need to fit a Viton seal, but it'll only cost a few pence more and if by some mischance you run the pump dry for a minute, this'll be less likely to overheat and fail than a normal seal.

If you decide to and/or replace the whole pump, then the Yanmar E pump is Yanmar part number: 128397-42500. However in the real world, this is actually a Johnson F4B-903-10-24509-01 pump, with a different face plate and painted grey; whilst the Johnson pump will only cost you about 50% of the 'genuine' Yanmar one's price, I should warn that it's not painted 'Yanmar grey', nor does it come in a cute polythene bag with the Yanmar logo on it, but if you can live without those, it's a direct replacement; even the mounting bracket's included.
 
OK, if you want to rebuild, the parts needed are:
Bigger bearing – S62012RS
Smaller Bearing – S60012RS
Seal – SEAL2-VITON 12-24-7 R23 (double lipped)
O-Ring -11 x 2.4mm – 24N0116

These bearings are all stainless steel, whilst those you'll get in a Yanmar/Johnson Kit are not, which is why they corrode/die immediately the seal starts to leak and always need replacing along with the seal - good business.
The 'standard' seal is single lipped, but I chose the twin lipped version on the basis that two seal faces are better than one; similarly, you don't need to fit a Viton seal, but it'll only cost a few pence more and if by some mischance you run the pump dry for a minute, this'll be less likely to overheat and fail than a normal seal.

If you decide to and/or replace the whole pump, then the Yanmar E pump is Yanmar part number: 128397-42500. However in the real world, this is actually a Johnson F4B-903-10-24509-01 pump, with a different face plate and painted grey; whilst the Johnson pump will only cost you about 50% of the 'genuine' Yanmar one's price, I should warn that it's not painted 'Yanmar grey', nor does it come in a cute polythene bag with the Yanmar logo on it, but if you can live without those, it's a direct replacement; even the mounting bracket's included.
Many thanks, I'll look for a source for these items tomorrow.

I need to read properly!

Richard

Eh??? :)
 
...
If you decide to and/or replace the whole pump, then the Yanmar E pump is Yanmar part number: 128397-42500. However in the real world, this is actually a Johnson F4B-903-10-24509-01 pump, with a different face plate and painted grey; whilst the Johnson pump will only cost you about 50% of the 'genuine' Yanmar one's price, I should warn that it's not painted 'Yanmar grey', nor does it come in a cute polythene bag with the Yanmar logo on it, but if you can live without those, it's a direct replacement; even the mounting bracket's included.
It would appear that the UK importers of Johnson Pumps, Aquafax, cannot get the F4B-903-10-24509-01 pump as it is not listed as available. They indicated that Yanmar have an agreement with them not to supply without the expensive Yanmar poly bag!!

Unless someone knows where | can get the F4B-903-10-24509-01 Johnson pump without the Yanmar bag???
 
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