I recently had a sudden engine stoppage. We had been motoring for about 32 hours non-stop and the engine suddenly died. My first thought was out of fuel, I checked. Tank 1/2 full.
Next
-I pulled off the bleed screw on the primary filter housing. No fuel visible. No visible leaks in the fuel lines from the tank to the (2) secondary filters, primary filter, and lift pump.
-I refilled the filter and bleed system via the manual lever on the lift pump I noticed that the external spring on the the manual lever was broken. The lever does not return up. Restart engine and ran for 1 hour. I stopped engine and again checked the primary filter and fuel level was down but the engine had not stalled.
As we were entering a new harbor I was nervous about another engine stoppage, I fitted an electric fuel pump in line. The engine has now run 2 + hours with no issue.
- I drained off the bottom of both secondary filters (FRAM unit), fuel appeared clean and normal.
-The fuel tank level. Top of tank about 12 inch above the manual lift pump and the bottom of the tank about 12 inch below the pump.
About 50 hours ago I change all fuel filters. So I had about 46 hours of engine time before the stoppage.
To me it seems that the manual lift pump is not keeping up the the fuel demand and the fuel level is slowly dropping in the primary filter???
How long is the run of hose from the fuel tank to the engine?
It is possible the lift pump has decided on early retirement but you may have some other issues as well. If you can remove the fuel pick up from the tank, I suspect that you may find some blockage which will cause exactly what you described. If there is a screen at the pick up, just remove it and reassemble everything carefully without it. Then check all fuel hose connections for possible leaks. If the hose is hard, it is possible for it to lose its seal on the hose barb and allow air to enter the system.
If you have air in the filters, instead of fuel, the problem is seldom the pump although it is the first thing that everyone blames.
An electric lift pump will work but make sure that it is a low pressure pump (1.5 to 3 PSI). If you use a higher rated pressure pump, by pass the mechanical lift pump.
The Hose length from tank to engine about 42 inches. With the new engine installation I fitted all new hoses and a new fuel tank. Unfortunately I can not (easily) remove the fuel pick up but I can inspect the lower portion of the tank.
Had the same problem. First time I blamed my fuel filters, changed them and all was well for about 40 hours. When the problem reocurred I dug deeper. Problem was exactly as Stanley described. There was a blockage in the screen in the pickup tube.
I was tempted to remove the screen but figured it took 18 years to block so I will revisit the end of the season. Having read Stanley's advice, I think I will remove it and let the fuel filters do the job.
I do not have a screen on the fuel pick-up. I disconnected the fuel line and blew back into the tank. Hopefully that will dislodge any potential blockage. Unfortunately there is NO way to pull the tube out, to remove the tank involves removing the engine! I can get access to the lowest point on the tank through the fill pipe. I pumped of about a 1/2 qrt from various points. Clean. We motored about 1 1/2 hours today and I checked the vent point and all was OK.
I removed the electric pump. It is a FACET pump but I see no P/N so not sure about the psi rating. Also refueled so that puts the fuel level above the filters. We have alot of motoring to do in the next 3 months. So time will tell. I'll keep you posted.