Yanmar 2GM20 Water Pump hose

[Upnorth]

Decided to think about fitting a speedseal to my water pump. Anyway in the process of measuring the back plate I noticed that the feed hose from the seacock on the sail drive to the water pump was oozing black stuff, so decided to remove it and get a replacement length of pipe. Thought that would be easy - except that I have now discovered the diameter of the spigot on the seacock is 18mm whereas the spigot on the water pump is 13.5mm! The jubilee clip on the water pump end had squashed the pipe badly.

Anyone come across this and how did they solve it?

 

[Laurie]

Have been in contact with Speedseal last year who told me that they do not do a seal for this engine/pump, nor intended to make one. Has something changed?

 

[Upnorth]

No they are not making one. I was measuring the plate in response to an enquiry to speedseal, when I discovered the issue withe seawater feed hose.

 

[prv]

Have been in contact with Speedseal last year who told me that they do not do a seal for this engine/pump, nor intended to make one. Has something changed?

As far as I'm aware, it's a standard Johnson pump so whether or not Speedseal think they do one for this engine doesn't really matter, as long as they do one that will fit the pump (possibly labelled as for a different engine). However, it's of questionable value because of the pump being mounted "backwards" so you can't easily just slip off the cover anyway.

I don't know what the seacock on a Yanmar saildrive looks like (mine was shaft drive) but can you not unscrew the 3/4" hose barb and fit a 1/2" one with the same thread? ASAP will sell them, make sure you get DZR or bronze and not brass.

Pete

 

[pete]

Don't know if these are any good
http://www.autosiliconehoses.com/si...e-hoses/straight-reducing-silicone-hoses.html
http://www.ebay.co.uk/itm/Straight-...-Rubber-Coolant-Joiner-Pipe-Air-/290640466201

I fitted a new speed seal to my Yanmar 2GM20F last season it has the ptfe disk in it to reduce wear on the impellor.
Pete

 

[Spyro]

Fit a new spigot/hose tail on the sea cock you'll never get a good seal otherwise.

 

[Upnorth]

Pete,
Thanks for the links to the reducers, look like they may work.

Think you must have a different pump on your engine. Speedseal confirmed today that they don't do a cover to fit my pump which has a 58mm dia cover plate. I was wanting to fit the ptfe disk version also to reduce impellor wear.

 

[prv]

Think you must have a different pump on your engine.

Entirely possible - there are two flavours of 2GM20, ones assembled in Japan and ones assembled in Europe (which have an E in the serial number). I believe the pump used is one of the differences between them. One uses paper gaskets and the other an O ring which is much more convenient.

Pete

 

[akyaka]

On first sourcing a spare impeller for our then recently installed 2GM20 we found that we had a larger size than in the parts list. The explanation from Yanmar was that it had been assembled in Holland and at that time they had run out of the standard model so had fitted a larger model.

 

[earlybird]

Is you don't wish to/ can't, change the hose tail size, (best solution IMHO), Vetus do a stepped hose adaptor, HA1338, which has 13 & 19mm diameters, throw the rest away. With a new bit of 13mm hose, provides a less elegant, but simple solution to your problem.