Undoing the nut on a yanmar 3gm Help please?

**knewboater** · 01-12-06, 18:07

Was on a friends boat today and wanted to change the fuel filter cartridge, the filter is in a very inacessable place so to undo the nut at the top of the filter case we thought we could tap it with a screwdriver and hammer, as there is not enough room for a spanner, then we thought this maybe the wrong way to attack it and someone out there might know better, so can anyone help? it would be much appreciated.

**Lakesailor** · 01-12-06, 18:16

You need a filter wrench http://images.google.co.uk/imgres?im...3Doff%26sa%3DN. You can stick a screwdriver through the canister and undo it that way, but it allows fuel to leak all over.

Is it a disposable one like this?

**knewboater** · 01-12-06, 18:21

No it is a metal bowl which has a paper cartridge inside and a nut like collar at the top which presumably unscrews. Thanks RGH

**pvb** · 01-12-06, 18:29

Have a look at http://83.162.27.211:83/yanmar/Yanmar.gm-series.pdf maintenance guide. There's a little exploded drawing showing how the fuel filter housing is removed by unscrewing the retaining ring.

**steve28** · 01-12-06, 18:36

Using a flat bladed screwdriver with some insulation tape or masking tape over the end (to protect the ring a bit), drive the retaining ringclockwise when viewed from above, as a tip its a good idea to replace the o-ring on the top of the filter bowl as well.

steve

**knewboater** · 01-12-06, 18:53

Thank you all very much for your help,should be ok now.RGH

**Burnham_Bob** · 02-12-06, 19:21

it's probably the same as on my 1GM 10 and that does need a strap wrench - I got a metal one from a car spares shop. The only prtoblem I have is that I have to loosen off the banjo nut at the side to get enough clearance to get the strap wrench all the way round the slotted ring at the top. It then comes off fine - if you can remember which way to turn it! Hammers and screwdrivers would worry me a bit!