2GM20 musings

MagicalArmchair

MagicalArmchair

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My 2GM20 is pre 1996 raw water cooled unit and I like to think is well maintained, serviced and lovingly fettled every year and has never let us down. I have no idea how many hours its done as that was never logged by the previous owner.

I recently thought to spoil said engine with a Speedseal, only to get the wrong one arrive. On talking to the manufacturer, they said they didn't make the Speedseal for such old engines and they seemed a bit surprised to find someone still using a pre 1996 2GM20. I had always considered the 2GM20 one of Triolas strong suits.

How many other folk have a pre 1996 2GM20 raw water? I've always had the feeling the engine, well maintained, will outlast me - or do people replace these units routinely? Newer engines scare the life out of me, all high pressure, very fuel fussy beasts that have to adhere to very strict environmental controls?
 
I wouldn't consider that an old engine particularly. Perhaps it rather reflects Speedseal's view of how many people might want to buy for that engine, they certainly make Speedseals for much older engines.
 
I have a 1993 3 gm30f runs lovely. I thought about a sped seal but I have bought 6 thumbscrews to replace the original bolts.
 
I got a Speedseal about 15years ago for a 2gm30 of 1970’s vintage. TBH, and as is now the situation with my 1999 3gm30, it was a waste of money. Easier to remove the bolt holding the pump and twist the unit round to change using a screw driver.

If that is the customer service from the company who obviously have no idea of the longevity of a Yanmar, I’d forget them.
 
MagicalArmchair said:
My 2GM20 is pre 1996 raw water cooled unit and I like to think is well maintained, serviced and lovingly fettled every year and has never let us down. I have no idea how many hours its done as that was never logged by the previous owner.

I recently thought to spoil said engine with a Speedseal, only to get the wrong one arrive. On talking to the manufacturer, they said they didn't make the Speedseal for such old engines and they seemed a bit surprised to find someone still using a pre 1996 2GM20. I had always considered the 2GM20 one of Triolas strong suits.

How many other folk have a pre 1996 2GM20 raw water? I've always had the feeling the engine, well maintained, will outlast me - or do people replace these units routinely? Newer engines scare the life out of me, all high pressure, very fuel fussy beasts that have to adhere to very strict environmental controls?
Click to expand...

There are two issues here. First how long will the engine last. It is half way or more through its life - but such engines rarely wear out. Typically in the second half of their life they suffer from neglect and lack of use as the boat slips down into the nautical equivalent of banger territory, often changing owners frequently and spending lots of time mouldering away in damp boats. There are regular threads on her raising the dilemma of what to do with a structurally sound, low value boat from the 70s and 80s where the engine is no longer reliable or economic to repair. Your engine is not likely to go like this because you will look after it and can expect at least another 20 years life.

The second issue is the likely demand for a Speedseal. Generally people buy them because access to the pump is awkward (as in a 1 GM) or they don't like the fiddly little screws why always want to make a run for the bilge! However it is an expensive bit of kit for what it is and arguably not the sort of thing that gets on the budget of an older boat. I am sure if there was a demand for one to fit your pump they would make it.

I am a fan having had one on a 1 GM, a Volvo 2030 and now about to fit one on a new D1 30, but can see why it is not a must have for others.

Don't worry about newer engines. They are much better than your old Yanmar (good though it is of its type and age). They are still mechanical and no more difficult to work on and maintain, plus being quieter smoother and freshwater cooled. The only possible downside is the electronic control panel on the latest types, but they seem reliable and the engine can still be started and run without the electronics in an emergency.
 
MagicalArmchair said:
My 2GM20 is pre 1996 raw water cooled unit and I like to think is well maintained, serviced and lovingly fettled every year and has never let us down. I have no idea how many hours its done as that was never logged by the previous owner.

I recently thought to spoil said engine with a Speedseal, only to get the wrong one arrive. On talking to the manufacturer, they said they didn't make the Speedseal for such old engines and they seemed a bit surprised to find someone still using a pre 1996 2GM20. I had always considered the 2GM20 one of Triolas strong suits.

How many other folk have a pre 1996 2GM20 raw water? I've always had the feeling the engine, well maintained, will outlast me - or do people replace these units routinely? Newer engines scare the life out of me, all high pressure, very fuel fussy beasts that have to adhere to very strict environmental controls?
Click to expand...

What they answered is not quite correct! I have a boat with a 2GM20. Engine about the same age as yours, and going strong. It had a Speadseal impeller cover which was fitted by a previous owner. I contacted Speadseal last year for some spare O rings, and they said they were surprised that such an old engine was still in use, and they did not make these any more for the 2GM20!! But then they said that they might still have one and would have a check in their stores, and phone me back. They did phone back, as they "found" a spare cover, and I bought it.

Perhaps not many people fitted them to a 2GM20, as the cover plate faces backwards. So you have to unbolt the pump mechanism anyway to change the impeller.
 
I sold my boat last year. It had a Yanmar 2QM15 installed 1980. It started first time provided the battery was in good nick. It has no glowplugs but it does have decompression levers and a starting handle! The only major replacement was to replace the exhaust elbow. When laid up out of the water I always ran inhibiting oil emulsion through the seawater system and occasionally renewed the internal anodes. I treated the engine badly insofar as it ran mainly in short bursts and at low revs but it just kept working and providing power! "If it aint broke.........."
Years ago I fitted a Speedseal but on reflection replacing the screws with thumbscrews would have sufficed. I currently own a 20 year old Volvo M2010 which, compared to the simplicity of the Yanmar is a pain in the ass. Speedseal informed me that they don't have a plate to fit my raw water pump. I have bought 6 thumbscrews!
 
I'm surprised that the Speedseal guy (believe the company is basically just one guy) thinks this is an obsolescent old engine.

As Keith says, perhaps they never sold many because the product doesn't work particularly well on an engine where the pump faces backwards.

Pete
 
With access to a lathe, making a Speedseal lookalike is very simple. Just a disc of 1/8" brass plate with an O-ring groove trepanned on one side. I made one for my 2GM20, not so much for the ease of impeller change, but to replace the fragile paper gasket with a more durable 0-ring. A suitable size ring can be bought or, more readily, super-glued up from nitrile rubber cord.
The Johnson pump on my present Beta 25 comes with o-ring seal as standard.
 
We’ve got a 2GM from pre-2000 and it’s great. No idea how many hours it’s done but its simplicity is its strength. Not much to go wrong and very easy to maintain even for a Luddite.

No idea what a speedseal even is,. Do I need one?
 
That's what I had on mine - my mate is handy with a large. It took him about 15 mins.
earlybird said:
With access to a lathe, making a Speedseal lookalike is very simple. Just a disc of 1/8" brass plate with an O-ring groove trepanned on one side. I made one for my 2GM20, not so much for the ease of impeller change, but to replace the fragile paper gasket with a more durable 0-ring. A suitable size ring can be bought or, more readily, super-glued up from nitrile rubber cord.
The Johnson pump on my present Beta 25 comes with o-ring seal as standard.
Click to expand...
 
NDG said:
We’ve got a 2GM from pre-2000 and it’s great. No idea how many hours it’s done but its simplicity is its strength. Not much to go wrong and very easy to maintain even for a Luddite.

No idea what a speedseal even is,. Do I need one?
Click to expand...

It's a replacement cover plate for the water pump, which is easier to remove and replace than the standard one. Four screws instead of six, two of them stay in place and act in slots to guide the cover into place so you only actually remove two, and the plate seals with an O-ring instead of a paper gasket that needs to be cleaned off and replaced each time. Thus it should be a lot faster to replace a damaged impeller if necessary at sea.

They also have a newer variant with a PTFE lining that's supposed to prevent damage if the impeller is run dry, but I'm dubious since the other edge of the blades and their tips are still running on the metal as before, it's only one edge that's teflon.

They supply the kits with a plastic widget intended for removing the impeller, which doesn't work.

As discussed above, a SpeedSeal is less useful on a 2GM20 because your water pump faces backwards so it's still not quick to change even if it had a quick-action cover plate.

Pete
 
On a 2GM20 as someone has said, the water pump faces backwards but it's fairly simple to remove the fixings and twist it round so that the cover is facing you.
You still have the problem of removing six fiddly little screws WITHOUT DROPPING THEM IN THE BILGE. For this reason people often replace the little screws with Allen key type or thumb screws. It's easy enough to remove the cover in calm conditions but more tricky at sea when it's rough and mistakes are more likely.
 
MagicalArmchair said:
I recently thought to spoil said engine with a Speedseal, only to get the wrong one arrive. On talking to the manufacturer, they said they didn't make the Speedseal for such old engines and they seemed a bit surprised to find someone still using a pre 1996 2GM20. I had always considered the 2GM20 one of Triolas strong suits.
Click to expand...
He was just a bit miffed that he did not have a product he could sell you ...
 
I had a 2GM 20 which gave excellent service until one spring when it started running rough and spewing clouds of smoke.
After throwing loads of money at it the final diagnosis was corroded exhaust port which meant a new head.
The cost of that plus all the ancillary bits like gaskets etc was more than half the cost of a new Beta. [plus several weeks loss of use].
No contest.
 
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