2GM20 cooling hose bore?

prv

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KS's engine has been out for the last couple of months, originally for overhaul but then stayed out to allow me to refit things behind it. One of those things is a new raw water system from the ball valve up. Since the skin fitting was 3/4", I've carried that size through without really thinking about it, to the hose ready to join the engine. However, it now occurs to me that I don't actually know if that's the size of the hose barb on the pump, and I suspect it probably isn't.

Anyone know what size hose the pump is expecting, and also the other points on the engine (by the thermostat etc) ?

Cheers,

Pete
 
KS's engine has been out for the last couple of months, originally for overhaul but then stayed out to allow me to refit things behind it. One of those things is a new raw water system from the ball valve up. Since the skin fitting was 3/4", I've carried that size through without really thinking about it, to the hose ready to join the engine. However, it now occurs to me that I don't actually know if that's the size of the hose barb on the pump, and I suspect it probably isn't.

Anyone know what size hose the pump is expecting, and also the other points on the engine (by the thermostat etc) ?

Cheers,

Pete

You'll should find the answers on page 1-23 of http://tinyurl.com/ygjulbb ( service manual, 3rd on the list at http://www.motoren.ath.cx/menus/yanmar.html )

Alisdair
 
You'll should find the answers on page 1-23 of http://tinyurl.com/ygjulbb ( service manual, 3rd on the list at http://www.motoren.ath.cx/menus/yanmar.html )

Alisdair

Just a note of caution: that link takes me to the manual for the 2GM, not 2GM20 - I don't think it makes any difference to the raw water pipe, but other things might be different.

2GM20 piping - inlet 20mm dia x 3.5mm wall = 13mm ID



2GM20F piping - inlet 24mm dia x 3.5mm wall = 17mm ID - a bit of a ******* size!



Andy
 
Thanks Andy - was about to say the same thing about the 2GM :-) (cheers for the effort though Alisdair - would have been close enough if the 2GM20 version weren't available)

I do have the Yanmar 2GM20 service book (as PDF), but I didn't find the piping diagram in it. Was I just looking in the wrong place, or did your image on photobucket come from some other publication?

Cheers,

Pete
 
Plus, any suggestions for a 20mm-13mm reducer? Looking at ASAP it looks like I'd have to take a BSP reducing fitting and screw a pair of hose tails into it, which seems a bit big and clunky.

Pete
 
I do have the Yanmar 2GM20 service book (as PDF), but I didn't find the piping diagram in it. Was I just looking in the wrong place, or did your image on photobucket come from some other publication?

The diagrams are in the back of the "Operation Manual" - these came from the web somewhere a few years ago (I didn't scan them), but they are the same as the paper manual I have.

Andy
 
The diagrams are in the back of the "Operation Manual"

Ah ha - I have a paper one of them I'd forgotten about - and so it does have a piping diagram in the back. Thanks.

Hmm... That suggests the inlet is 17mm dia on the 2GM20.

All bets are off :D

Yeah, saw that.

I'm aware that both Japanese and European 2GM20s exist, and that the water pump is among the slight differences between the two. I know from the serial number that mine is a Euro one; I have to assume the manual I have is correct for the engine, and the fact that it's in various european languages tends to confirm that. My manual says 13mm hose - maybe the 17mm is for the Japanese version?

Pete
 
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