yanmar 2 gm20 f

[colin59]

Hi ordered a mtc kit for this which included oil filter, impeller etc. The impeller did not fit as mine has a key inside that attatches to the pump drive and this one did not and came with a gasket while mine has an o ring. This was the correct kit according to the marine store parts catalogue. Stumped now as to why. Anyone had this problem with parts?
thanks
Colin

 

[Tally Ho]

Not sure….

I have a 2GM20F. My cover uses a paper gasket (no o-ring). My impeller does have the key, however. I did purchase an impeller once that did not have the key.

Probably have to find out what exactly is included in the kit before you buy it, or buy the parts separately. Once you find the right one, buy a few or save the link for future purposes.

This one looks close, but no O-ring for the cover.
SCP Marine Diesel Maintenance Service Kit Y002 for 2 1/4" Cover Yanmar Marine Sea Water Pumps 128270-42000, 124070-42000, 42001, 42002 https://a.co/d/2TgGXI5

This kit has the impeller and an o-ring…
SOXAMarine 09810B Impeller Repair Kit For for Jabsco 653-0001 Mallory 9-45713 Yanmar X08810B Sierra 18-45713 Amazon.com

I see this note on the Toad Marine website (a good reference for Yanmar parts)..

Common Parts for the 2GM20F Model Engine Printer Friendly Version Common parts for other engines Is it time to repower? Help to identify your engine​ Horsepower: 18 Produced from: 1983 to December 2005 Series: GM/HM Bored Up series About the GM/HM Bored Up series: Similar to the earlier standard GM/HM series, these engines provide upgraded horsepower and a 55 AMP alternator (1GM10 35 AMP). Special Note: If your engine serial number starts with an "E" you must make sure that you use parts for the YEU engines. For example, if you have a 2GM20 with a serial number starting with E you actually have a 2GM20YEU. The (YEU) engines are European manufactured and now more common in the United States than the Japan built models.

 

[colin59]

Thanks Greg, I do have the e version of the engine. After making some calls and digging around the internet did find out that after 1996 this was indeed the case. and were exported. I have a 2000 hunter 290.The marine store here did not know about it and after I suggested they get Yanmar to explain it to them so people dont find out after they order in line. The fuel filters and oil filters are the same. The E serial engines parts seem to all start with 128990 with suffix 42570 for impellerr. It comes with 6 bolts to attatch and an O ring....I would have thought a reputable marine store would have known this being a Yanmar dealer!!!.....Hope I am the only one who has to deal with this...
cheers, summer is near!!
Colin

 

[Calif. Ted]

It's a Johnson pump that is made in a couple configurations, the original on mine had a cross rod that fit the end like first image and used Johnson 810 impellor. When I replaced with a Yanmar boxed replacement pump it came with a keyway for the impellor and uses Sierra 18-8950 impellor (second image). Which do you need?

 

[colin59]

Thats correct Ted, the second one comes with a paper gasket which wont work in the E serial # engines and is what is included in the 2gm20f kit which is not correct for the E ser # engines… quite confusing not inly for the novice sailkr bjt also some yanmar parts dealers….

 

[colin59]

Sorry for the grammar… thick thumbs on an iphone keypad!!!!
Colin

 

[ggrizzard]

Colin,
Yes I had the same problem. If I had known about Toad Marine maybe I wouldn't have found out the hard way.
My solution was inadvertent. I bought a series E pump as a backup pump for the older style
(not knowing there was such a change) 'cause I wanted a spare pump. Then, I bought an impellor not knowing about the difference. It was the old style. Now, I have both styles so that if I'm somewhere that never heard of the change, I'm still covered! And when I order another impellor, I know how to spec the correct version for each style pump.