I bought a Ranger 482v with a CMC jack plate Hydraulic and a 150 fast strike Model J150GLERA about a year and a half ago. Have done minor maintenance over the past year new Vro, plugs a few times, fuel water separator, decarb. The boat has a Raker 24 14 1/2 my gps top speed was around 58 59 mph with me and a co-angler at about 5300 to 5400 rpms. Jack plate set slightly up and trim to rpm/ speed. Boat always was a bit rough off idle but ran like a champ. Move forward to this year and 2nd outing out I hit some rocks and had a new lower installed and prop redone. Went through break in and now am searching for my old performance. For some reason the boat can only do about 53 at best, but mostly 50, more alarming is the difficulty I have getting RPMs above 5000. I actually over trim to get rpms and lose speed. I am constantly searching for performance with JP and Trim.
I know my initial thoughts were prop/lower unit. The Lower is a SEI unit and I am just coming off break in. It is supposed to be same G-ratio as factory. I will verify. The problem is if the prop was say less pitch my RPMS would be like 5700 to 6 with a lower top speed or the opposite lower rpms with a respectable top (guessing). Maybe the repair was so bad on the prop that it just sucks.
That brings me to the motor. The motor doesn't have that rpm jump it used to. I checked compression last night while engine was warm and it was like 80-85psi but I forgot to open throttle wide open so I think it is more. The important thing is they were all within 3 psi or so. Actually all were the same except one that was about 3 or so less.
Any suggestions where to start? i checked 4 of the 6 high speed orifices (other 2 could access) they seemed tight. Motor is definitely very rough off idle to about 2000 rpms. I am going to take a closer look tonight. I do think I am missing the clear wrap on the carb roller. I noticed that last night. Pretty sure that's been like that since I got the boat. Quick start works, primer seems to work, idles out of gear around 800. I have a factory manual/aftermarket easy timer .
Could I be misfiring or running on 4 or 5 and not know it? I would think the motor would be very rough throughout its range. I assume the mechanic put lower unit on correct and exhaust baffle is in place. Any suggestions on where i should start would be great. I cant stand it when something just isn't right.
Frustrated,
Mike from Upstate NY