Join Date: Sep 2011
Location: Dolphin Beach, B.C.
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Re: Bleeding screw fuel injection pump Yanmar3gm30f
If you do bleed both filter bleed screws, bleed the primary first and then the secondary filtre's bleeder. If you do it the other way around you will just introduce more air into the system again.
That's why I only bleed the secondary as it is after the primary filter and this will evacuate all the air that has been introduced into the system. It also helps to fill the filter canisters with fuel before reinstalling them.
You shouldn't have to bleed the high pressure end of the system unless air has made it's way in there somehow by running it out of fuel, trying to start it without bleeding the filtre's first, or by having worked on that part of the fuel system, etc.
If it's just a simple change of filtre's and you have not done "anything" else you should be ok by just bleeding the secondary's bleeder.
We have three rules;
No bleeding on the sails.
No slobbering on the charts.