water pump impeller issues, answers needed

[FullCircle]

£YM30 well known for pump wear problems - the rear shaft seal wears out the shaft after about 500 hours.

Aquafax Luton 2011 prices.....

Get it in bits from Aquafax Luton

F4B-903
10-13337-01
which is fitted to the 3YM30. You will need this number when phoning



Impeller & Cover gasket 09-810B-1 £20.51

Bearing Front 05-08-124 £6.28

Bearing Rear 05-08-130 £9.80

Seal 05-29-139 £3.59 2 required

Shaft 01-46541 £38.00

all plus VAT

 

[Scillypete]

£YM30 well known for pump wear problems - the rear shaft seal wears out the shaft after about 500 hours.

Aquafax Luton 2011 prices.....

Get it in bits from Aquafax Luton

F4B-903
10-13337-01
which is fitted to the 3YM30. You will need this number when phoning



Impeller & Cover gasket 09-810B-1 £20.51

Bearing Front 05-08-124 £6.28

Bearing Rear 05-08-130 £9.80

Seal 05-29-139 £3.59 2 required

Shaft 01-46541 £38.00

all plus VAT

Thanks for all that it will come in very handy, all the replies seem to tending towards the pump being knackered'ish, so rather than get a speedseal cover I've got a new one which has got it going normally so far. next step if it plays up is to refurb the pump with the parts listed above and if that does the job I will then add the speedseal if not it'll be new pump time

 

[charles_reed]

Thanks for all that it will come in very handy, all the replies seem to tending towards the pump being knackered'ish, so rather than get a speedseal cover I've got a new one which has got it going normally so far. next step if it plays up is to refurb the pump with the parts listed above and if that does the job I will then add the speedseal if not it'll be new pump time

Have never had to replace a shaft, or cover-plate in 2100 hrs. Bearings and seals necessary and (IMHO) the Speedseal a waste of money if you use s small socket. Impellers do 300-800 hrs. In the 2100 hrs I've had the engine have only bought 5 replacement impellers. I've now got 2 spares as well as a spare raw-water pump.
I've found the Johnson Pump considerably less trouble than the previous Jabsco I had on my 2GM, which led to my always carrying a spare raw water pump.
However, if the Johnson stops pumping at less than full pressure and the impeller is not shot, I automatically rebuild it.

 

[FullCircle]

Thanks for all that it will come in very handy, all the replies seem to tending towards the pump being knackered'ish, so rather than get a speedseal cover I've got a new one which has got it going normally so far. next step if it plays up is to refurb the pump with the parts listed above and if that does the job I will then add the speedseal if not it'll be new pump time

Pete.
Those are all the components to build a pump. The cost of those added up, is less than the amount Yanmar want for a new pump, and Johnson cannot sell you a whole one.
I had to be very shady to get those part numbers, as they do not appear in the Johnson spares book, because they are Yanmar commissioned items.

So build yourself a pump for mucho cheapo.

 

[Trundlebug]

Don't forget to coat the impeller (especially the ends) with either silicone grease or some waterproof grease before fitting.

It helps seal any minor gaps to compensate for wear, and makes a huge difference to priming.

It also helps to protect from overheating if it runs dry for any reason.

No, the grease doesn't harm the impeller.

 

[charles_reed]

Pete.
Those are all the components to build a pump. The cost of those added up, is less than the amount Yanmar want for a new pump, and Johnson cannot sell you a whole one.
I had to be very shady to get those part numbers, as they do not appear in the Johnson spares book, because they are Yanmar commissioned items.

So build yourself a pump for mucho cheapo.

Surprised about all this cloak & dagger - the pump is a standard Johnson pump, bought by Yanmar for fitting to their marine engines - on the two occasions I've bought from Johnson there has been no problem. The only thing they couldn't provide was a replacement water-pump pulley.

Here are the prices as of Jan 2012
01-46541 Shaft £16.62 each
05-08-130 bearing £4.33 each
05-08-124 bearing £4.78 each
05-29-139 seal £6.20 each
01-45050 plastic spacer £6.44 each
09-810B-1 Impeller £23.52 each

Quite a difference on the ASAP price and quite openly e-mailed to me. However shoe, pump-body and faceplate are likely to be far more in total, so building a new pump from scratch is probably not as economical as inferred but re-conditioning is.
My complete new pump was £150.63.

Still the conspiratorial view of history provokes far more debate than what actually happened.

 

[Scillypete]

Thanks to everyone for all the useful replies of which there are many, this is the first time I have had an issue like this, normally its change the impeller and forget about it for a few years or longer. Each of these new ones has been greased with the little pouch of stuff that comes with them, nice slippery stuff that makes it easier to get them into the pump. Hopefully the new cover will have done the job and only time will tell.

Amazing how such simply engineered bits of kit can cause the most problems

 

[FullCircle]

Surprised about all this cloak & dagger - the pump is a standard Johnson pump, bought by Yanmar for fitting to their marine engines - on the two occasions I've bought from Johnson there has been no problem. The only thing they couldn't provide was a replacement water-pump pulley.

Here are the prices as of Jan 2012
01-46541 Shaft £16.62 each
05-08-130 bearing £4.33 each
05-08-124 bearing £4.78 each
05-29-139 seal £6.20 each
01-45050 plastic spacer £6.44 each
09-810B-1 Impeller £23.52 each

Quite a difference on the ASAP price and quite openly e-mailed to me. However shoe, pump-body and faceplate are likely to be far more in total, so building a new pump from scratch is probably not as economical as inferred but re-conditioning is.
My complete new pump was £150.63.

Still the conspiratorial view of history provokes far more debate than what actually happened.

Charles, the Yanmar is cost reduced....lower spec.

 

[Piers]

Having read the comments, I'd agree that the likely issue is an air leak. Maybe, when fitting the new impeller the grease is sealing the air leak, yet after use the grease has dispersed leaving the air leak vulnerable again. You could test this by inserting the same one you remove, with grease, and see if the issue recurs.