It probably won't show a fault unless it's under a load. Granite
My Merc 135 OPti has been in and out of the shop a half dozen times in the last few weeks. I have faith in the local marine shop. They have tried everthing they can think of and they have been on the phone with Merc a half dozen times or more and they are scratchin their heads too!! When they hook it up to the computer it says no faults. They told me today that the Merc factory tech is comeing next week to see what he can find.
It runs great once it gets up on plane and it will jump up on plane the first time or two each time I take it out but after that it really struggles to get up on plane and sometimes won't. The heavier the load the worse it runs.
Had my grandsons here from out of state this week and they were pretty disapointed that they didn't get to spend more time fishin with grandpa but it's really been too hot for them anyhow.
It probably won't show a fault unless it's under a load. Granite
For your info , My bass buddy has a 175 Optimax on his Ranger , Has the same problem , His local shop can't find the fix either.!!!!
If they can't find it, try running it on a portable tank. A friend of mine had a fuel pickup problem that took almost a year to find. It would run great for a while, then go to heck. They finally figured it out when he noticed it ran better more often at lower fuel levels.
Thanks Fishawk, I wish you luck, that 175 has been to the shop Three times no fix yet.
Please post the what the problem was. My Mariner is doing the same thing, won't plane out and only gets up to about 2000 rpm's...my mechanic couldn't figure out what the problem was either and I hate throwing $$$ down the toilet.
There's nothing like feeling that THUMP...FISH ON
My 225 opti was doing the same thing and i had it in the shop three times with them putting it in the tank with no problems.I would get to the lake and it wouldn't come out of the hole to save itself. Finally took it elsewhere and told the tech it had to be in the water to do it he put it in the lake and didnt go 50 feet before he looked at me and said the Reed valves were out of it.
Sure enough he got it apart and the reeds were broke off.1800.00 later runs like a top.
There will be days when the fishing is better than one's most optimistic forecast, others when it is far worse. Either is a gain over just staying home.