Join Date: Oct 2007
Location: Beacon Falls CT USA
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Fuel starvation cause?
I've got a 1993 Universal M4-30, 25hp in my 1972 Hughes/Northstar 38. A few years back I replaced the fuel 'lift pump' assuming it was the cause of intermittent engine failures after long running.
The failures continued. So I rewired the circuit, replaced all the lines, changed all the filters and had the tank professionally cleaned. I even installed an in-line squeeze ball as a work-around so if I get in a pinch I can keep the engine running. A few squeezes and I can keep the engine from slowing running down to a stall. In fact, a few sqeezes returns the engine to normal operation for about 5 minutes...then it's back to squeezing.
Last night on my shakedown cruise it happened again, after about 4 hours of operation. I tried openning the fuel tank cap thinking it was possibly a clogged breather that might be creating a vacuum - no luck. It was back to squeeze-ball life-support. The next day, today, the boat ran fine on a 3 hour motor sail. But I am near certain it will happen again.
Before I go and do exploratory surgery on the pump, or ultimately throw it away and buy a second replacement, can anyone else think of anything it may be?