Zagato
Well-Known Member
Just wondered if anyone new how much they are (a cheap source 
) and how difficult it is to do yourself, or cost to have it done - thanks.
) and how difficult it is to do yourself, or cost to have it done - thanks.
Replacing an Exhaust Elbow on a Yanmar 2GM20!
- Thread starter Zagato
- Start date
ghostlymoron
Well-Known Member
When I last checked, they were about £130. I think ASAP do them. Shouldn't be too difficult to change depending on access. The flange bolts could take some shifting if you're unlucky. A boat engine mechanic should do this comfortably in a couple of hours probably charge £120.
I think it's wise to check the condition annually. This also has the advantage that it stops the bolts 'welding up' too much.
I think it's wise to check the condition annually. This also has the advantage that it stops the bolts 'welding up' too much.
Zagato
Well-Known Member
Thanks, seems your spot on with the price. I'll get some plus gas on the bolts, take it off and let the engineer fit it 
It hasn't been done in 15 years so will need doing, the Crabber built after mine has just had his removed and all was OK apart from a bit of corrosion so hopefully mine will be OK also. They both should have been checked years ago
Will ask them to check the cutless bearings and stern gland whilst he's at it.
It hasn't been done in 15 years so will need doing, the Crabber built after mine has just had his removed and all was OK apart from a bit of corrosion so hopefully mine will be OK also. They both should have been checked years ago
Will ask them to check the cutless bearings and stern gland whilst he's at it.
pete
Well-Known Member
Depending on access they are easy to change, 3 or 4 nuts and 2 pipes to remove.
I have been in touch with
http://www.exhaustelbow.com/
who make replicas, he supplied us with a batch of 3 last year for members at our sailing club but they were for 1GM10's and 2GM20 RAW WATER COOLED and have a 3 hole flange he said he will be making a batch of 2GM20 FRESH WATER COOLED exhaust bends next January these have a 4 hole flange.
His 1GM10 ones were around £57 each inc delivery from memory for 3 last year but the 2GM20 F ones appear to be about double that price.
You will also need to replace the gasket.
Pete
I have been in touch with
http://www.exhaustelbow.com/
who make replicas, he supplied us with a batch of 3 last year for members at our sailing club but they were for 1GM10's and 2GM20 RAW WATER COOLED and have a 3 hole flange he said he will be making a batch of 2GM20 FRESH WATER COOLED exhaust bends next January these have a 4 hole flange.
His 1GM10 ones were around £57 each inc delivery from memory for 3 last year but the 2GM20 F ones appear to be about double that price.
You will also need to replace the gasket.
Pete
emsworthy
Well-Known Member
Zagato,
If you are anywhere near Emsworth (well Westbourne to be more precise), there's a chap called Diggy Barnes who works out of the Old Dairy Workshops who will make a better quality part than you could buy from anywhere and I reckon he'd do it for about £50-£60!!
He would turn it around in a day or so in my experience.
In terms of removal/fitting as long as you can get to it it's a fairly simple job.
If you are anywhere near Emsworth (well Westbourne to be more precise), there's a chap called Diggy Barnes who works out of the Old Dairy Workshops who will make a better quality part than you could buy from anywhere and I reckon he'd do it for about £50-£60!!
He would turn it around in a day or so in my experience.
In terms of removal/fitting as long as you can get to it it's a fairly simple job.
Zagato
Well-Known Member
Thanks for the tips and links.
A stainless steel elbow... Mmmm shiny Detail the engine, chrome up the pipes, under light the engine bay and finish it all off with a perspex lid
A stainless steel elbow... Mmmm shiny
Detail the engine, chrome up the pipes, under light the engine bay and finish it all off with a perspex lid 
Cloven
Well-Known Member
I've done this job on my 2GM20F and it was fairly easy. As others have said, make sure you are getting the right one for your engine 20GM20 or 2GM20F as they are different.
Also, again as already mentioned, you will need a new gasket. In fact, I would recommend buying a couple of spare gaskets as the exhaust elbow is really something that should be checked on a fairly regular basis and even if not needing replaced, you will need to fit a new gasket each time you remove/refit the elbow.
Hope this helps
Also, again as already mentioned, you will need a new gasket. In fact, I would recommend buying a couple of spare gaskets as the exhaust elbow is really something that should be checked on a fairly regular basis and even if not needing replaced, you will need to fit a new gasket each time you remove/refit the elbow.
Hope this helps
savageseadog
Well-Known Member
The hardest part will be getting the exhaust hose off. You can use Sikaflex for the gasket.
Spyro
Well-Known Member
Thanks, seems your spot on with the price. I'll get some plus gas on the bolts, take it off and let the engineer fit it
.
If you can take it off you can put a new one on in 15 mins.
rob2
Well-Known Member
A few years back we fitted a Yanmar twin in a friend's boat. Took the exhaust stub to a local welder to get a water injection facility added. He cut away the original stub, turned out the flange to fit an inner sleeve, added the outer to suit the hose and the injection port all in stainless. Cost was around a tenth of the OEM part!
I really love the idea of UV underlighting for the engine bay! Was reluctantly chatting with a guy in the pub who kept playing with a remote to make his Harley light up in four colours of flashing lights. We moved to another table...
Rob.
I really love the idea of UV underlighting for the engine bay! Was reluctantly chatting with a guy in the pub who kept playing with a remote to make his Harley light up in four colours of flashing lights. We moved to another table...
Rob.
Cloven
Well-Known Member
Quite agree - I had to replace the short section from the elbow to the waterlock when I did mine.
Zagato
Well-Known Member
The stuff of nightmares if we ever see a Kev & Mel furry dice culture for poor taste, bling boats, doing doughnuts in the channel!
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Zagato
Well-Known Member
How does the mixer elbow work? Is it like a non-return valve letting water and exhaust only go in one direction 
Tranona
Well-Known Member
No. The water is injected into the exhaust stream and provided the engine is running it will be expelled with the exhaust gases. There will be a waterlock to stop water coming back up the exhaust pipe and probably an intsyphon valve which lets air in when the engine stops to prevent water in the pipes syphoning into the engine. The only time water might get in is if you crank the engine without it firing so the water pump is still pumping water in, but no exhaust gases to expel it. That is why you should never crank for long periods with the seacock open.
System is pretty idiot proof if properly installed.
System is pretty idiot proof if properly installed.
pete
Well-Known Member
How does the mixer elbow work? Is it like a non-return valve letting water and exhaust only go in one direction
Its a pipe within a pipe, the outer pipe takes the water around the inner pipe, that takes the exhaust fumes, the inner pipe stops about 35mm before the outer one.
Pete
davidwf
Well-Known Member
They tend to fail where the pipe is welded onto the flange, if so just get it welded up again.
Cloven
Well-Known Member
Maybe - but my last one failed where the water from the small inlet pipe was directed onto the hot pipe in the centre of the elbow that carries the exhaust gasses. Not at all obvious at first as I only took it off to clean it out and that's when the full extent of the corrosion became evident as I cleaned all the carbon deposits off the inner pipe.
pete
Well-Known Member
Of the three corroded ones I have seen they had all gone halfway down the internal pipe it's not that obvious but with the flange at the bottom and with your finger blocking the small water inlet spigot carefully pour water between the inner and outer pipes and see if any comes out of the flange end (you can usually see down the inner pipe where it is leaking from)
I have just checked the one on my recently purchased boat and it needs replacing. I carefully ground around the inner part of the flange to release the inner pipe when removed it.It didn't look bad but had a few pin pricks in it.
I bent a new piece of thicker walled 316 stainless pipe and using stainless wire welded it in with my MIG using CO2 as that's all I have (not ideal) but the bend is now refitted and I will check it out again at the end of next season.
Pete
NPMR
Well-Known Member
IGM10 exhausts are notoriously rotten. Barrus reccommend inspecting every 300 hours as it can ruin a head and valves if they start to leak back.
I have complained several times to Barrus (the importers) that the Yanmar design is poor, and that after umpteen years in production and endless examples of people making them from scratch for less cost they are wildly overpriced.
At one time, they wrote to tell me the price was going down but it seems to be unchanged from what I see.
Blatant profiteering is my opinion. I assume nobody stands up to them and complains or they might have done something about it by now! I did my bit but one voice ......
I have complained several times to Barrus (the importers) that the Yanmar design is poor, and that after umpteen years in production and endless examples of people making them from scratch for less cost they are wildly overpriced.
At one time, they wrote to tell me the price was going down but it seems to be unchanged from what I see.
Blatant profiteering is my opinion. I assume nobody stands up to them and complains or they might have done something about it by now! I did my bit but one voice ......
xeitosaphil
Well-Known Member
Just wondered if anyone new how much they are (a cheap source
As others have said, if you can get it off, it’s a ten minute job to refit.
Unfortunately when I did mine, as part of a major refit on the engine when I purchased the boat, the bolts were rusted and welded in. Use load and loads of freeing fluid such as plus gas over a period of a few days. One of mine sheared off and I had to drill pilot hole in broken off bolt, and use screw extractor to remove it. Engine was out in the cockpit at the time under a temporary covered workshop erected over the cockpit, but it was still a job to get it out.
Hope you have an easier job than me, best of luck?