Help - Lost RPMs

[atlantis]

If everything else checks out, we would be glad to measure in your wheels for you.

Takes about 10 minutes and is free.


Ray- 856 231-0106

[Fortunate One]

When was the last time you adjusted the valves?

[hubris 1]

check for a blockage in the fuel lines. been there done that. i know you wont believe it but i had the same issue years ago. i drove me nuts, only to discover that the saddle tank that split and got welded......well, welding pieces got caught at the pickup blocking fuel flow. ok i fixed that after two full days in north carolina trying to find the problem. next year i got a new main tank. when they installed the fittings they let the drill shavings go right into the tank. everyone of them was in the fuel line. still twisted, and blocking the supply for total rpm. one engine had more than the other but it held the other down. my first guess would have been a turbo problem, but ill bet anything it aint the wheels, shafts, or cutlass bearings. the engine when getting enough fuel.....has enough power to twist the balls off a monkey! you would have to have an anchor line on the shaft to impede performance. if the engine checks out. its fuel. good luck.

[Fast Forward]

I am not really an egine guy but if both sides are down equally, and the running gear and bottom are ok, I would look at the engines or fuel. Whatever it is sounds like it is the same problem on both sides. Therefore two bad pickups, cutlass, props, etc. is where I would look last, although stanger things have happened. Did the problem get worse over time or just pop up?

[Nimrod]

OK - I've been on the road and water a lot lately with little time to devote to SFC. Here is a brief review of what we ended up with.

Had the boat hauled and a number of projects taken care of while on the hard. No real obvious issues sttod out but we went ahead and did the following:
Replaced all 6 cutlass bearings
Repacked all shaft and rudder stuffing boxes with GFO packing
Replaced all 8 engine motor mounts
Aligned both engines and shafts
Removed both shafts and check for trueness
Had props checked and polished (they were within designated ISO Class Tolerances)
Painted bottom
Reapplied PropSpeed to running gear (less props)
New zincs

Results:
Boat is running famously. Engines are turning up factory spec 2350 RPMs with speeds of 26-27 knots at cruise and 32 knots WOT - not bad for an old gal. Everything is smooth as silk and the steering is noticably easier to turn.

Thanks for all the input and suggestions (many of which were taken to heart while getting the work done). The crew is happy again and hopefully we can all find some time to use her.

[Questsportfishing]

I think your supposed to go out and pat her on the side and say 'good girl'... glad your running good! tight lines kid!

[hubris 1]

Originally Posted by Questsportfishing

I think your supposed to go out and pat her on the side and say 'good girl'... glad your running good! tight lines kid!

i always do that, ask anyone thats fished with me. i talk to the boat at least twice a day. in the morning i tell her what i expect of her, and coming home, i say nice job Hubris. i pat her on the controls. even if fishing sucked, i dont blame hubris, shes just a girl.

[clt_capt]

Originally Posted by hubris 1

i always do that, ask anyone thats fished with me. i talk to the boat at least twice a day. in the morning i tell her what i expect of her, and coming home, i say nice job Hubris. i pat her on the controls. even if fishing sucked, i dont blame hubris, shes just a girl.

Does she puke often???

[hubris 1]

Originally Posted by clt_capt

Does she puke often???

well of course she has........but if i make a big deal out of it, well i just tell her its morning sickness. and then she lets me know she wants new engines. oh yea, and an interior too.

[T380Fisher]

Originally Posted by Nimrod

OK - I've been on the road and water a lot lately with little time to devote to SFC. Here is a brief review of what we ended up with.

Had the boat hauled and a number of projects taken care of while on the hard. No real obvious issues sttod out but we went ahead and did the following:
Replaced all 6 cutlass bearings
Repacked all shaft and rudder stuffing boxes with GFO packing
Replaced all 8 engine motor mounts
Aligned both engines and shafts
Removed both shafts and check for trueness
Had props checked and polished (they were within designated ISO Class Tolerances)
Painted bottom
Reapplied PropSpeed to running gear (less props)
New zincs

Results:
Boat is running famously. Engines are turning up factory spec 2350 RPMs with speeds of 26-27 knots at cruise and 32 knots WOT - not bad for an old gal. Everything is smooth as silk and the steering is noticably easier to turn.

Thanks for all the input and suggestions (many of which were taken to heart while getting the work done). The crew is happy again and hopefully we can all find some time to use her.

Nimrod....for future knowledge, did you figure out which of the "fixes" fixed your problem? What was the real cause of the lost rpms? It seemed like you took a replace everything approach, which worked, but sounds awefully expensive if it was just 1 motor mount or some line wrapped or a clogged filter. Also, you stated the shaft always was hard to turn after about an hour of running. Is this still the case or has that issue been resolved as well?
Anyway, glad to hear you got the "old gal" running out properly.