RACOR water separator on Yanmar 2QM15

[Sylvain]

My Yanmar 2QM15 is very difficult to start now.
History: When I picked up the boat on Lake Michigan, the batteries were completely dead.
The boat had been sitting at the marina well over a month.
Once we got a new battery it started.

I got the boat shipped by truck to Henderson Bay, NY, and harmed with new batteries, tester and charger, I cleaned up the terminals and got the electrical working. But it took a hell of a lot of cranking to get it started.
The only way to start it (again 20 seconds 3 or 4 times) is at full throtle.

Things I've done:
Last week: Filled the tank.
Today: Changed the fuel filter and drained the Racor water separator.
I noticed that the 230R unit has a R20S filter on it.
Now isn't a 2 microns (R20S) filter intended for final filtration instead of primary? They make a 30, 10 and 2 microns filter. Wouldn't it be the source of my problem?

 

[Ken Honeycutt]

Racor recommends a 30 micron for primary. Don't know if that's your problem but if the boat sat for a long time you could have some nasty stuff floating around the tank that got stirred up during the delivery (I had a bad experience with dirty fuel because of a similar situation). You may have to polish the fuel to get all the gunk out..either that or plan on changing the filter constantly until you get clean fuel.
I had to start my old 31' Hunter at near full throttle..don't think that is anything unusual.

 

[Benny]

You are correct about the filters but that in itself should not be your starting problem. It sounds like the starter might not be crancking fast enough if you can only get it started at full throtle. Check the ground connection all wiring; if not have the starter load tested.

 

[jtm]

Two things to check- To ensure you don't have a science project growing in your fuel tank, disconnect it and splice in an external tank with new clean fuel- see how that works/runs.

The other point is to ensure- your electrical contacts and/or wiring are not corroded up and that you are not experiencing some voltage drop.

But it sounds like you are able to crank for an extended period of time! These Yanmars only need 2 things and they kick over easily- clean fuel and air. I'd definitely try the external tank route - a lot easier and you will know in short order if its crud in your fuel.

Further on that last comment -I'm not familiar with the layout on the H33 but You might also want to ascertain if you have stand alone self contained poly tanks for the fuel tank and the buble box -OR if they are "side by side" and of the molded-in design. The years may have opened a glassed over caulk seam between the 2 molded tanks and your buble box may be infiltrating and poluting your fuel.

 

[dfriha]

another option

I had this problem and it turned out to be a leak in the o ring at one of the fuel injectors which did not allow compression to take place until the engine was warm. Find a good Yanmar mechanic to check it our.