This motor had the old canister style water separator at the base of fuel tank that had no filter in it. A second filter housing is new for the motor. We just drained all the old fuel and let a biodiesel set in the tank. We then rinsed it and then refilled. I don’t know if the tank has a screen.
Diesel fuel lines
- Thread starter Tom H31
- Start date
Got the line primed and motor is running but it is still not running the way it was. It will run for a bit and then die. At a low idle it will not run well. Is it possible to still have some air in the line?
i installed an automotive electric fuel pump on my fuel line, at a convenient location. and a toggle switch next to it on the alden 40 ish years ago. it's between the fuel tank and the first filter. i suggest all boats could use this approach. over time all engines have repairs and will need to prime the system. the electric automotive fuel pump is cheap. get them anywhere.
i do not believe that the engine will fire with even slight air in the line. just my observation.
had my injection pump rebuilt this past aug. was down 5 days. my machine shop checked their records and the last time i had it rebuilt was 01'. i was having slow rpms when cold. it was obvious the engines start up had changed from the norm. i reviewed the worn parts with the machine shop. parts were worn. only working at 50% ish. injection pumps do wear. the specs on fuel pumps are tight. the rebuild work area looked like an operating room only cleaner. the bill was 1,800.00 for just the machine shop. the parts on my 52 year old engine, a perkins 107, are now getting harder to find.
the joy of old toys
i do not believe that the engine will fire with even slight air in the line. just my observation.
had my injection pump rebuilt this past aug. was down 5 days. my machine shop checked their records and the last time i had it rebuilt was 01'. i was having slow rpms when cold. it was obvious the engines start up had changed from the norm. i reviewed the worn parts with the machine shop. parts were worn. only working at 50% ish. injection pumps do wear. the specs on fuel pumps are tight. the rebuild work area looked like an operating room only cleaner. the bill was 1,800.00 for just the machine shop. the parts on my 52 year old engine, a perkins 107, are now getting harder to find.
the joy of old toys
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Yes, it is possible, but the first symptom of air in the system is hard starting. If is starting but not coming up to speed, i would suppect fuel starvation.
However, starvation usually happens at higer revs when more fuel is demanded.
I would remove both fuel filter elements. Try it. if it runs properly replace one element and then the other. Don't worry about running the little Yanmar with no filter for a while. It can take it, maybe.
Blackout Hi, Hope that by now you have solved your problem. I want to share with you my experience because I think you could be fighting the same problem. More than 15 years ago I had similar problem, trying to solve it I replaced all my fuel lines, removed the primer hand pump that came with my H 29.5 and still could not solve my problem, it will idle fine but once we were under way the engine will die. Finally one of our experts sailing members told me to remove the strainer Hunter placed in the bottom of the fuel pick up tube and the problem was solved. The amazing thing was to see what Hunter had done, they have placed a tiny metal mesh strainer of the size of the ID of the fuel pick up tube, maybe 3/4" in diameter, it was completely clogged and my boat was only 7 years old. Problem solved, never had that problem again.
I purchased a vacuum gauge when I had this issue. I had a restriction at the pickup tube.
Bugger to get cleaned out but all good now. It’s nice having the gauge inline now after my raco and before the engine filter. No more guessing. Just my 2 cents. Good luck, I know how frustrating it can be.
