Bleeding a YSM8

[csoule13]

For you Yanmar YSM8 owners, any tips on bleeding the engine?

When changing the fuel filters in the past, I've been unsuccessful at doing this. In particular, cracking the nut at the fuel feed pump and wiggling the stupid handle that's supposed to pull fuel in. A gazillion pumps later, and I never see the tell tale signs of the air having been pumped out.

I have a screen on fuel filter/water separator, and my process is to fill the replacement with clean fuel, screw it into place, then start down stream trying to bleed the system. Would cranking the engine over a few times help get things moving a little and make this easier?

Chris

[tjr818]

This is what we had to do - only one time though:

Screen Shot 2020-11-01 at 12.24.36 PM.png

[vsail]

Yes cranking the engine helps. At least that is the way I bled YSM 8. Slightly opening the bleeding screw on top of the filter and making sure diesel seeps out after you crank. Make sure you leave a rag by the screw to catch the diesel. The manual lever has never worked for me. If you are still in the water, I usually put a load on the prop either forward or reverse to make sure all air is out of the system. I've stalled before I thought I was good to go.

Hope this helps and good luck.

[radsailor]

from previous experience many years ago, I opened the bleed screw and turned over the engine until it started and diesel spurted out of the bleed screw. This required two people. Other would have made a huge mess if I had to jump from the cockpit to the engine the tighten the screw. I found the little pump lever to be useless.

[BernieA]

I don't have a yanmar, mine is a Volvo. The priming pump has been frozen since before I bought the boat. To bleed, I bought an online pump like you find between gas tanks and outboards. When I change the primary and secondary filters I use the pump to bleed the system. Once the filter bleed points show no bubbles, I start the engine and bleed the injectors. It's worked well for me.

Bernie
Cd28
S/V Pinafore
Sequim Bay, WA,

[Frenchy]

My small experience with mechanical engine-mounted fuel pumps such as on the Beta 25 and Yanmar 1GM is that
the hand lever will move rather easily for a certain distance and then stop. If you're moving the lever through this
arc, you get nowhere. You have to push down hard when you reach the lower point of resistance. Then, you'll feel
the pump working. You may have to hand turn the engine a bit to get the actuating arm off the cam.
As for a outboard-type squeeze bulb in the fuel line, that's controversial. I don't think the USCG or ABYC
approves - mostly because the rubber is not as fire proof as the A-1 fuel hose. I understand there are those who
use it anyway. - Jean

[BernieA]

As for a outboard-type squeeze bulb in the fuel line, that's controversial. I don't think the USCG or ABYC
approves - mostly because the rubber is not as fire proof as the A-1 fuel hose. I understand there are those who
use it anyway.

I hadn't heard that before. If it isn't accepted by the USCG or ABYC, why does virtually every outboard that uses portable tanks have a bulb in the fuel line?

Bernie

[mgphl52]

Interesting dialogue... KAYLA came with a bulb and I use it every time I start the engine. If that bulb was a "risk" in case of a fire, the boat would be gone long before the bulb... Just saying!

[Frenchy]

From what I've read the ABYC does not approve of any fuel squeeze bulbs used below decks because
it may be a fire hazard. Apparently, it's more dangerous there than in an open cockpit. I don't know about
the USCG - there may or may not be restrictions.
I'm not an ABYC member so I don't have free access to their regulations but perhaps someone else on
this board does. - Jean

[csoule13]

Thanks for the tips and encouragements. Also happy to see the discussion this tripped off. I think it's easy to think that something as foundational as this must be straight forward.