Yanmar 2GM20 Diesel Leak

SteveIOW

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Ran my 2GM20 today. Started easily and ran well (as usual) but I happened to notice an occasional, but regular, drip of diesel from the connection of one of the high pressure fuel supply pipes with one of the injectors. I was able to tighten the union nut, which pulls the pipe end into the injector, a little but this made no difference to the drip rate. I wondered if there was a copper washer within the injector which I could renew but my Yanmar manual does not show one,
Can anyone please suggest how I should fix this small leak?.
Has anyone else had this problem with this engine and solved it?
 

penberth3

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Ran my 2GM20 today. Started easily and ran well (as usual) but I happened to notice an occasional, but regular, drip of diesel from the connection of one of the high pressure fuel supply pipes with one of the injectors. I was able to tighten the union nut, which pulls the pipe end into the injector, a little but this made no difference to the drip rate. I wondered if there was a copper washer within the injector which I could renew but my Yanmar manual does not show one,
Can anyone please suggest how I should fix this small leak?.
Has anyone else had this problem with this engine and solved it?

I've never seen a copper washer in this position. There should be a conical fitting on the end of the pipe. Unlikely to leak here but it's possible. It's also possible for injector pipes to crack inside the union nut. Tightening the nut will not cure this.
 

vas

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as @penberth3 says, they are just conical fittings. Remove said pipe and get a new one made (doubt there's enough slack to cut and reflare).
TAKE GREAT CARE, when refitting (and removing) on the diesel high pressure pump side as you have to hold the 19 or 21mm don't remember now nut underneath it steady, if it turns even 10deg the pump settings for this injector are gone and it's a high pressure pump out job :-(
Search some threads by me over the last 3-5yrs re my problems with a 2gm and you'll see how I know :rolleyes:

cheers

V.
 

vas

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no need to shout, should explain that F on all these yanmars (well 2GM and 3GM) means that it's fresh water cooled. Rest is the same.
no worries, prefer to post here if I know/gone through something as in this case.

cheers

V.
 

UK-WOOZY

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no need to shout, should explain that F on all these yanmars (well 2GM and 3GM) means that it's fresh water cooled. Rest is the same.
no worries, prefer to post here if I know/gone through something as in this case.

cheers

V.
caps was unintentional, sorry. i use CAPS by default as a draftsman and was replying quickly and have a rotten cold so couldnt be bothered to correct it after i realized too late, sorry
 
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SteveIOW

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Thanks vas for advice at Post 3. Have ordered a new Yanmar HP Pipe. When it eventually arrives I will be very careful not to disturb the large "nut" on the pump. Will try to find some way to lock it so that it can't move.
 
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