2GM20 Engine replacement / Antifoul removal service in Kent?

UK-WOOZY

UK-WOOZY

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I have a Yanmar 2GM20 on my Jeanneau Sundream 28, since i got the boat 3 years ago, Its had new engine mounts by poly flex, exhaust elbow, thermostat, filters and filter holders, anodes, raw water pump and a refurbished starter. It is still making a strange metallic rattling noise in the background. (tappets have been checked, loose bolts, ruled out alternator etc.)
I had the gearbox off to try and get to the source of the metallic jingle noise and thought while its off I may as well get it serviced. I was quoted £1400 my M.I.T in Queenborough, almost the cost of a new gearbox. I am now thinking instead of spending more money on the 2GM20 I would like a new engine that way I have all new components and peace of mind instead or worrying what else might go on the old engine.

What new engines are there that I could buy as a direct replacement to the 2GM without having to adjust the engine beds, also I assume they go for around £5K. I contacted Beta and they recommended the Beta 20 but didnt give a price.

Antifoul:

Are there any antifoul removing companies in Kent? I contact Symblast but due to distance its £450.

many thanks
 
cannot really help in any of your questions, just wondering about the course of action you're planning.
if you've already done all that, is an engine swap really worth it?
is the 5k for engine+box, or you're fitting your old one (with or without rebuilt)? means extra money
my 2GMF also makes some metallic noises at certain rpm and it's been professionally rebuilt and only done 20h since, but it's on a generator.
 
If the engine starts and drives properly without making too much smoke or burning lots of oil Id leave it alone and just go sailing. Same applies to the gearbox-----change the oil and leave it alone as long as it works. Lockdownitis can lead to lots of worry and too much money spending. I went out for a day sail last week for the first time since February and I feel much better already!
 
Biggles Wader said:
If the engine starts and drives properly without making too much smoke or burning lots of oil Id leave it alone and just go sailing. Same applies to the gearbox-----change the oil and leave it alone as long as it works. Lockdownitis can lead to lots of worry and too much money spending. I went out for a day sail last week for the first time since February and I feel much better already!
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the noise was bothering me since last years season
 
vas said:
cannot really help in any of your questions, just wondering about the course of action you're planning.
if you've already done all that, is an engine swap really worth it?
is the 5k for engine+box, or you're fitting your old one (with or without rebuilt)? means extra money
my 2GMF also makes some metallic noises at certain rpm and it's been professionally rebuilt and only done 20h since, but it's on a generator.
Click to expand...

the noise comes on after a few seconds of starting the engine and is there at all revs. i get some white smoke too every time i throttle
 
I replaced my GM20 with a Beta 20 about 4 years ago. Almost a direct replacement. I raised the beds by about 20mm but not strictly necessay, I just wanted to keep the feet adjustment centalised.
Headroom was a bit tight in my case, had to make a short hose gadget to fill the oil. Length was OK, I think I had to cut a bit off the propshaft but easy with a hacksaw. All done afloat, much easier than I anticipated.
The cost of spares to repair the Yanmar made the decision easy.
As is often the case, I thought "why didn't I do this sooner?"
 
Dan Tribe said:
I replaced my GM20 with a Beta 20 about 4 years ago. Almost a direct replacement. I raised the beds by about 20mm but not strictly necessay, I just wanted to keep the feet adjustment centalised.
Headroom was a bit tight in my case, had to make a short hose gadget to fill the oil. Length was OK, I think I had to cut a bit off the propshaft but easy with a hacksaw. All done afloat, much easier than I anticipated.
The cost of spares to repair the Yanmar made the decision easy.
As is often the case, I thought "why didn't I do this sooner?"
Click to expand...

Access to the engine on my boat is pretty good. can access the top, front and back easily. which boat do you have?

vid of how it is on mine-


1.jpg
 
I replaced a 2GMF with a 3YM20. Same engine bed but new holes required tapping for forward mounts. Your prop shaft will not require change (mine needed ~12mm lopped off but different g'box). Exhaust and heat exchanger on other side, makes starter and alternator access more difficult. 3 cylinders is much smoother. Take video of old engine ~£1k+ on eBay.
 
Watching your video and listening to it running, it sounds just normal to me. You have a small 2 cylinder diesel engine and will always make more irregular sounds than more balanced engines with more cyliders. Do not compare it to a petrol engine sound either. Remember it is an industrial engine converted to marine use and was never designed to be extremely quiet. Personally you are an engineers delight - a customer with a wallet to be milked. Stop worrying about it until something stops the engine completely. If are still concerned then spend some time learning how to sail to pick up a mooring or go alongside a pontoon. These are skills you hope you will never need but should be learnt.
 
Concerto said:
Watching your video and listening to it running, it sounds just normal to me. You have a small 2 cylinder diesel engine and will always make more irregular sounds than more balanced engines with more cyliders. Do not compare it to a petrol engine sound either. Remember it is an industrial engine converted to marine use and was never designed to be extremely quiet. Personally you are an engineers delight - a customer with a wallet to be milked. Stop worrying about it until something stops the engine completely. If are still concerned then spend some time learning how to sail to pick up a mooring or go alongside a pontoon. These are skills you hope you will never need but should be learnt.
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but i have heard other 2GM'S on youtube and theres someone at our club with the engine and it doesnt make the metallic jingle. its also the fact that parts are costly for the engine and im thinking why spend more in parts when its will all add up to a new beta etc
 
UK-WOOZY said:
Access to the engine on my boat is pretty good. can access the top, front and back easily. which boat do you have?

vid of how it is on mine-


View attachment 91067
Click to expand...
I have to say your engine sounds sweet, I'd be happy with that.
In my case the engine in my UFO 31 coughed and ran backwards for a bit, then would only run on one cylinder. I decided a top end overhaul might help, so engine into the cabin, ££££££s spent on gaskets, injector service, feet and other bits. No improvement on re-installation. The yard engineer asked how much more money I was going to throw at it. All this was at the start of a season in a swinging mooring.
New Beta delivered and installed in 2 weeks. A friend had similar symptoms at the start of last season but decided to get the engine repaired. This resulted in a completely lost season and no confidence that it's completely fixed.
A thought, my old gearbox was fine, are there other dead engines with salvageable gearboxes you could buy.
 
UK-WOOZY said:
but i have heard other 2GM'S on youtube and theres someone at our club with the engine and it doesnt make the metallic jingle. its also the fact that parts are costly for the engine and im thinking why spend more in parts when its will all add up to a new beta etc
Click to expand...
you've probably changed most of the bits that need replacing, if you really WANT to replace, just do it. You could spent 200quid replacing and improving the insulation and pocket the rest of the money as far as I'm concerned!
 
Does noise change as the engine warms up? Does in increase in time with engine speed? Also try revving engine flat out max rpm and then pull the stop lever and listen for the noise as the engine slows to a stop. Is it still present or does it disappear? Also try disconnecting one cylinder at a time, either with the decompression lever or loosening an injector pipe. All trial and error, will narrow things down.
 
Dan Tribe said:
I have to say your engine sounds sweet, I'd be happy with that.
In my case the engine in my UFO 31 coughed and ran backwards for a bit, then would only run on one cylinder. I decided a top end overhaul might help, so engine into the cabin, ££££££s spent on gaskets, injector service, feet and other bits. No improvement on re-installation. The yard engineer asked how much more money I was going to throw at it. All this was at the start of a season in a swinging mooring.
New Beta delivered and installed in 2 weeks. A friend had similar symptoms at the start of last season but decided to get the engine repaired. This resulted in a completely lost season and no confidence that it's completely fixed.
A thought, my old gearbox was fine, are there other dead engines with salvageable gearboxes you could buy.
Click to expand...

my marine engineer who iv used many times has quoted me £1000 to remove the yanmar and install the beta, or i can come to an arrangement and pay with the yanmar. seems steep to me, also the pump alone was £600 under a year ago, PolyFlex engine mounts a year ago £650, Drive plate a few months ago £200, Elbow 2 years ago £150, Fuel filter housing on engine £80.
 
Change the oil and use fully synthetic oil sae 5w40. Really effective in reducing engine rattles.
And also add some injector cleaner to the fuel. White smoke indicates incomplete combustion and can create noise in the cylinders on combustion.
Add the can to the tank and run the engine under load ( ie in forward gear half throttle )for an hour or so to get the cleaner to work
 
Don't as suggested above run it on fully synthetic.Old marine diesels don't have the tolerances of design that synthetic is designed to be used on. Just chuck in bog standard mineral oil or you will damage it more.
 
UK-WOOZY said:
my marine engineer who iv used many times has quoted me £1000 to remove the yanmar and install the beta, or i can come to an arrangement and pay with the yanmar. seems steep to me, also the pump alone was £600 under a year ago, PolyFlex engine mounts a year ago £650, Drive plate a few months ago £200, Elbow 2 years ago £150, Fuel filter housing on engine £80.
Click to expand...
hence my suggestion on insulating the enginebox only in post #12 :-)
 
Concerto said:
Watching your video and listening to it running, it sounds just normal to me. You have a small 2 cylinder diesel engine and will always make more irregular sounds than more balanced engines with more cyliders. Do not compare it to a petrol engine sound either. Remember it is an industrial engine converted to marine use and was never designed to be extremely quiet. Personally you are an engineers delight - a customer with a wallet to be milked. Stop worrying about it until something stops the engine completely. If are still concerned then spend some time learning how to sail to pick up a mooring or go alongside a pontoon. These are skills you hope you will never need but should be learnt.
Click to expand...
Every sailor should know how to sail, pick up a mooring, moor to a pontoon or dock, drop and retrieve anchor with or without engine. All done without anchor preferably and using engine if there's a good reason. Too many so called sailors switch on the engine at the drop of a hat so never improve their sailing skills.
 
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