Bleeding air from Yanmar 2GM

Now that the weather is getting warmer, I'm hoping to get the boat into the water to use. I finally learned out to bleed the engine and getting it working again.
1981, Nor'sea 27, Rhapsody Blog: norsea27-rhapso...
Also watch the second part to this, Yanmar 2GM Post Winter Engine Testing: • Yanmar 2GM Post Winter...

[@alexanderholtet7463]

Hi. Have just changed filters and bled the fuel system on my 2gm20f and made a couple of "discoveries": The manual fuel pump on the side of the engine: The lever has a lot of play, but it is only the last little bit (5mm or so.) that actually pumps fuel, you will notice increased resistance here. However, pumping fuel from the tank to the engine by means of the manual pump takes forever (even longer when you forget to open the fuel valve on the tank...;-) ) I chose to juse the hand operated vacuum pump that I use to change oil to suck fuel to the engine, just disconnect the fuel line at the back of the engine, insert the tube from the vacuum pump with a couple of rounds of a suitable tape around it to seal it, an pump. When you have done this, bleeding the rest of the system with the manual pump is a breeze. Would also recommend to bleed all the way to the injectors to get an easy start afterwards. Conserning Davids question about the secondary filter, the ring unscrews clocwise (seen from the top), i used an adjustable wrench to get a grip on it, as mine was also very tight.

[@davidmansfield1337]

+Alexander Holtet - Thanks for that. Managed to replace the filter but not yet successful at getting fuel flow. I'll try your suggestion about sucking fluel through. I fear my little priming pump may have broken. I think by rotating the engine slightly you can get more than the 5mm you mentioned, but when there is no fuel in it then it is useless ?

[@AndysEastCoastAdventures]

+David Mansfield Try pumping it quicker, I found quick pumps filled the small filter chamber very quickly.

[@davis7099]

It is appreciated that people take the trouble to make explainatory videos for the help of others.. but.. this video could benefit from having a steadier camera and a clearer, more methodical a to b to c spoken description. Go to Sailor punk and Capt John's Skipper videos for more clear to follow 2GM yanmar air bleed instructions

[@farnorth7314]

Why is it every time I see an instructional video about bleeding a Yanmar they always miss the MOST IMPORTANT point...the lever on the pump has a stroke of about an inch, all but the last 1/4" of that is useless freeplay. The bottom bit of the stroke is what drives the fuel along and feels considerably heavier. HOWEVER if the pump is sitting on a high lobe of the camshaft that last 1/4 will not exist. If this is the case you must open the depression levers and roll the engine using the drive belts until that last 1/4 of the pump stroke exists. To try to bleed by simply flapping the lever through the free play part of the stroke achieves absolutely nothing. This video is a very poor attempt to show how to bleed a Yanmar GM series engine...find a Yanmar manual or take a proper course. The method shown in this video will create more problems than it solves.

[@W4ABN]

When this video was made, I was still very much inexperienced in the engine and my boat. This was never meant to be an instructional video but me just trying to figure things out and see if I could get this engine working again. A lot of time has passed since this video and I have learned a lot more. I have since cleaned it up and did a partial rebuild to keep it working. Again, I'm just sharing a bit about trying to learn more and figuring it out as I go. Thanks for stopping by.

[@AndysEastCoastAdventures]

I find that if you pump the primer lever on the pump really fast it works better. Done mine from complete empty this week, didn't even fill the new filter with fuel. Starting from the prefilter just undone the top bolt till fuel starting spilling out, then removed top bolt on small fuel casing completely as it expels air quicker then pumped the lever til it started pouring out the top and replaced bolt. Then undone the bleeder nut on the injection pump and pumped the lever again until fuel pouring out. You don't need to remove the pipes going from this to the injector. To start I lifted the decompression lever and spun the motor over with the starter for 10secs then dropped the lever and away she went. Been starting fine ever since. It was the first time I've tried it since I'm new to the boat and was rebuilding the cylinder head due to rusty exhaust valve & seat. It was easier than I thought it would be. My boat doesn't have those outboard primer bulbs. Why doers yours have these? Is the engine mounted quite high or the fuel tank low??

[@AndysEastCoastAdventures]

Is your prefilter lower than your fuel tank? It looks high up, mine sits behind the engine roughly same height as top of engine, maybe a little bit higher.

[@W4ABN]

+Andrew Polson Thanks for the tips. I'll try it a little faster next time and see how that works. The priming bulbs were there when I bought the boat. The fuel tank is low, like under the engine. The fuel pickup is about 2 feet down at the bottom of the tank, in the keel. You can see a shot of the tank in this picture: 4.bp.blogspot.com/-l-Y2KPVPnts/UckW-KO6JII/AAAAAAAABEc/lJ31cBXWbns/s1600/IMAG0285%5B1%5D.jpg This is my first boat so I'm learning along the way. I'm currently going through a refit too and part of that will be replacing the fuel tank, so the engine will have to be moved out of the way to get to it. It'll be a lot of work and it's been done by other Nor'sea 27 owners but I think it'll be worth it when it's all said and done. Thanks for stopping by. I appreciate the suggestions. That's why I put up the videos and post on my blog.

[@AndysEastCoastAdventures]

+W4ABN Explains why the primer bulbs are their then, bit like an outboard, but inboard instead.

[@AndysEastCoastAdventures]

Might be why the pump primer lever didn't work very well as well.

[@frankhughie6897]

S/V Harley Quinn is

[@phatista]

Nice. Thanks for sharing. I'm about to undertake the same project on my 2GM in a Hunter 27. BTW, the vibration is totally normal.

[@W4ABN]

Glad to know this will help. I hope it works out for you.

[@Gaiapozder]

May I ask the prop dimensions please?

[@parrishfloyd5684]

Yeah. I am having the same issue with my Hunter 33. Thanks for sharing.

[@multihull40]

Was hoping to get informed articulate video instruction of how to bleed the 'whole' system from someone who knew what they were doing! Be warned...13 minutes of nothing....

[@gmailoceanplurra]

Thanks !! Great help !

[@W4ABN]

You're welcome.

[@davidmansfield1337]

Could you please tell me briefly how to open up the secondary filter. Which way do I rotate the castleated ring around the top of the bulb ? Mine is very tight and hard to get to. Thank you, I am at my wit's end.

[@neiljones6748]

David Mansfield Its standard threading, lefty lucy. I use a flathead screwdriver set on one of the crenulations and a few light taps from a wrench to get the ring loose, then it should easily loosen by hand.

[@davidmansfield1337]

+Neil Jones Thanks Neil. Viewed from above it is clockwise to unscrew as the ring with crenulations goes down to come off with the bowl. Screwing back up is tricky as the filter doesn't stay central within the bowl. Thanks for your help.

[@AndysEastCoastAdventures]

+David Mansfield I did mine with plumbers pipe grip expandable pliers. Wouldn't budge by hand at all.