Yanmar 2GM20F - Bag of nails - Update

[Stoshak]

Many Thanks to the forumites who reassured me that the alarming noise and movement of my engine is normal and to be expected. My previous boat had a Beta which had given faultless , quietish service for 10 years so the Yanmar came as a bit of a shock.

The current engine is 3 1/2 years old, fitted in the boat from new, annually serviced as per book.

There was evidence of saltwater beneath the engine so I checked the waterpump the installation design of which was the work of an incompetent with a sense of humour. Spindle corroded. New spindle cost more than a pump assembly for Beta, and the Beta pump is from the same manufacturer, but only obtainable from Barrus mafia.

But seawater still evident, coming from corroded exhaust elbow. Elbow removed, heavily corroded and carbonised. Scrap, in fact and after only 3 1/2 years! New elbow, £130!
And no improvement in the design.

So the questions are

What other faults should I be bracing myself for?

The saltwater pump is by Johnson. Is there a generic pump type that can modified in the workshop to suit the Yanmar thus avoiding the cynical markups.

What can be done about the elbow? It is a complex double skinned design which clearly does not work.

Or, with an eye to the future, bearing in mind Yanmar's idea of what constitutes a consumable part, should I put it on eBay and get a nice new properly engineered Beta?

 

[charles_reed]

My experience of the 2GM20 is totally the opposite - it's now been changed after 17 years of use and replaced by a 3YM. Mind you mine was raw-water cooled with no heat-exchanger.

Johnson pumps are about 35% the price of Yanmar spares, on the 3YM they haven't tried to disguise the fact and I always use the Johnson parts. Don't know any Johnson dealers in UK, plenty round the Med.
I always carried a spare pump, changing the raw-water impeller was a far bigger task than changing the pump. Regular maintenance helps - I used to have the pump-body and the backplate re-machined. The weak point on that pump is the waterseal, but that's easy to replace.
On the 3YM they have the faceplate forward and an O-ring seal, so the changing of an impeller is about 35secs work.

With regard to the elbow, mine never corroded - I suspect you have a problem of galvanic corrosion - on the raw-water version there are 3 anodes (2 on the block and 1 in the head).
Most of the difficulties you're having point to incompetent installation - amongst professionals the marinised Kubota is not considered as reliable an engine as the designed-as-marine Yanmar.

John Skues of Cellar Marine is one of the best Yanmar pros around, but unreliable unless you can deal in person with him.

I sympathise with your experience of the Barrus distributors, but Antony Farrugia in Malta is even worse - deal, if you can with YanmarNV as a boat-in-transit.

Oh! last tip, Mazda 323 oil filter fits all the Yanmar 2GM-3YM range - you could try these people for more down-to-earth Yanmar parts

http://www.marine-power.co.uk/catalog/index.php?cPath=1_13

 

[NPMR]

You have my sympathies.

Whilst my Yanmar has been relaible as hell, the cost of parts and the like is stupid. And as I've posted many times, the UK price is usually the same in pounds as they are for dollars in the US - for the same parts!! So it has to be a mark-up thing.

As far as the elbow is concerned, I fought the price of this with Barrus and have a letter from them saying the price has been amended to £63.26 plus VAT. Their words "... now available at a recommended retail price of £63.26 plus VAT."

So if you are still being charged £130 you've been diddled in my opinion. The piece of bent tin they call an exhaust elbow needs to be changed every couple of years (Says John Skewes too) As the design must now be some 20+ years old, you'd have thought they'd have sorted it by now. A local fabricator made one for me from Stainless Steel and that only cost £40!!!

I too keep a spare water pump (bought in the US in DOLLARS) rather than fiddle with the impellor under the engine. And the whole pump cost about as much as the shaft would have done in the UK! It's much easier this way.

Crowning injustice? Yanmar won't let the US dealers sell to the UK - I have to go through my Brother-in-law in Illinois. Something about if they've got you by the b*lls etc etc.

 

[RMC]

I had a similar failure of the exhaust elbow with my 1gm10, mine was four years old, I contacted Barrus, returned the elbow and have been sent a cheque for the replacement cost.

 

[smth448]

Clever piece of design with my 1GM10 was that the water pump is directly above a high pressure oil feed pipe. When the water pump leaks it drips salty water onto the ouil pipe which corrodes, bursts and empties all the engine oil into the bilge! At least the oil pressure alarm worked

 

[Stoshak]

Thanks for the response, but the cooling exhaust elbow for the fresh water cooled variant is completely different from the sea water cooled engine. It is mounted at the rear of the heat exchanger as opposed to the stbd. side of the engine, and I think the internal geometry is different as well.

There is nothing wrong with the installation of the engine - by Jeanneau, to the book. No, I believe the problem is one of very bad design.

As far as I am concerned the Beta is very superior - a very well designed and developed base unit with millions of hours experience, with a British marinisation package that does the business without falling to pieces or blocking.

The 'special offer' price of a water pump assembly form the Barrus dealers is £297.20 (£327 for Japan built engines). The price of a similar Johnson pump from ASAP is £120 tops, all inc VAT.

The exhaust elbow, a Yanmar part, good for 3 years tops is £149,93. And I'm taking the old one round to the fabricators this week.

There is something decidedly unsavoury about organisations that screw yachtsmen in this manner.