Engine pop, 502 MPi, electrical?
08-27-2018 | 10:55 AM
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From: Virginia Beach
Engine pop, 502 MPi, electrical?
This hasn’t been my season; rain rain and more rain, plus fuel lines, electrical issues with bad bulkhead harness connectors, and lost/missing parts deliveries (though thankfully found). Now I have an intermittent “pop” out of the intake on my port engine, but I think it’s battery related. Read on...
i normally run the boat on #1, but start on All. The guys and I went out last week to test the new steering (phenomenal btw), and about 30 minutes into our run, the we started getting a pop out of the intake at 3k. It was enough to noticeably drop RPM. We stopped, took a look at some things, and went on our way. 15 minutes later, same thing. We decided to head home. All gauges were good. Decided to say f-it and ran the last 8 minutes or so to the inlet at 4300 or so. No issues. Got to the dock to eat, shut her down, and lost all power on the port side (was fun getting home in the dark with no nav lights). Next day, found that the power terminal had broken off at the starter. I put a new lug on it, soldered everything, and all was good.
Took her out Saturday, and she seemed to be okay. Alternator readings while on All were at 12 volts, but you could rev a little and she’d jump to 14. Switching to #2, she dropped to 11 but would still recover. Left batteries on #2. About 20 minutes in, we were running at 60 mph in some 3-foot chop, and I decided to drop the hammer; the engines cut off momentary (not good at that speed). Now concerned, I brought her back down to 3k to cruise carefully to our destination. She popped a couple times again, then showed no other issues until we anchored. While at anchor, and still on #2, we got all kinds of strange electrical activity. We cut the boat off. Heading home, we ran on #1 and had no issues.
Would a bad battery cause something like above situation? I pulled it last night, and it’s showing about 9 volts; it’s toast. I thought the alternator would keep things going once running, but perhaps the alternator cannot keep up with higher loads especially with the MPI set up.
Thoughts?
i normally run the boat on #1, but start on All. The guys and I went out last week to test the new steering (phenomenal btw), and about 30 minutes into our run, the we started getting a pop out of the intake at 3k. It was enough to noticeably drop RPM. We stopped, took a look at some things, and went on our way. 15 minutes later, same thing. We decided to head home. All gauges were good. Decided to say f-it and ran the last 8 minutes or so to the inlet at 4300 or so. No issues. Got to the dock to eat, shut her down, and lost all power on the port side (was fun getting home in the dark with no nav lights). Next day, found that the power terminal had broken off at the starter. I put a new lug on it, soldered everything, and all was good.
Took her out Saturday, and she seemed to be okay. Alternator readings while on All were at 12 volts, but you could rev a little and she’d jump to 14. Switching to #2, she dropped to 11 but would still recover. Left batteries on #2. About 20 minutes in, we were running at 60 mph in some 3-foot chop, and I decided to drop the hammer; the engines cut off momentary (not good at that speed). Now concerned, I brought her back down to 3k to cruise carefully to our destination. She popped a couple times again, then showed no other issues until we anchored. While at anchor, and still on #2, we got all kinds of strange electrical activity. We cut the boat off. Heading home, we ran on #1 and had no issues.
Would a bad battery cause something like above situation? I pulled it last night, and it’s showing about 9 volts; it’s toast. I thought the alternator would keep things going once running, but perhaps the alternator cannot keep up with higher loads especially with the MPI set up.
Thoughts?
