Hey all,
Searched forums and found some helpful topics, but not totally what is happening in my world, so here goes!
1999 Larson 254 with Merc 5.7 and Alpha drive. Boat was well maintained and had 51 hours on it when I bought it in spring. I have since put on 33 nearly trouble-free hours.
Early in season, after 11 hours or so, under heavy load (4 ppl + large dad-n-law) and in also in chop would get what sounded like a lifter tap at higher RPMs. Always made power just fine, but I backed her off just the same. I assumed it was a mildly used engine not used to normal running, and had the valves adjusted. Seemed to work, didn't hear noise again and timing was just fine. Ran like a top.
Last month, we go on vaca and it sits in the salt water for about 3.5 weeks, drive down. Tank was just below 1/4 full. On last trip oil pressure signal would sound occassionally at starting for around 30 seconds, but gauge read 40-50.
Came back to lots of growth on trim tabs and even on drive (this worried me), I scraped and cleaned most of it off. But now that rattle is back with a vengeance and she is running rough and occasionally stalls. I added about 5 gals of gas with stabilizer, ran it, changed the fuel filter (some water in it, but not much), changed the PCV.
Symptoms on first ride:
The
Searched forums and found some helpful topics, but not totally what is happening in my world, so here goes!
1999 Larson 254 with Merc 5.7 and Alpha drive. Boat was well maintained and had 51 hours on it when I bought it in spring. I have since put on 33 nearly trouble-free hours.
Early in season, after 11 hours or so, under heavy load (4 ppl + large dad-n-law) and in also in chop would get what sounded like a lifter tap at higher RPMs. Always made power just fine, but I backed her off just the same. I assumed it was a mildly used engine not used to normal running, and had the valves adjusted. Seemed to work, didn't hear noise again and timing was just fine. Ran like a top.
Last month, we go on vaca and it sits in the salt water for about 3.5 weeks, drive down. Tank was just below 1/4 full. On last trip oil pressure signal would sound occassionally at starting for around 30 seconds, but gauge read 40-50.
Came back to lots of growth on trim tabs and even on drive (this worried me), I scraped and cleaned most of it off. But now that rattle is back with a vengeance and she is running rough and occasionally stalls. I added about 5 gals of gas with stabilizer, ran it, changed the fuel filter (some water in it, but not much), changed the PCV.
Symptoms on first ride:
The
- at first the boat didn't want get on plane very easy, but did
- then the rattle started again, but now comes at much lower RPM (2200), I back it down right away
- will occassionally stall at idle, but rare
- Oil pressure gauge is reading 40-50, but low pressure warning signal sounds for a minute when starting. While running and warmed up, gauge will occasionally jump down then come back up. Sometimes even read high, over 60, then come back down.
- Temp stays normal around 160 ish
Oil is normal color and at full mark when warmed up.
No noises or sound when idling or under low RPM power
It's scheduled to come out for storage on Saturday. I just need to idle over to marina, plan on topping off fuel, and out she comes. I will be having a mechanic winterize and will have him check this out too.
What are the thoughts here so I'm confident he's taking the right steps?
Thanks!
