M
Mike Ramont
Guest
" have a 1987 Merc. 454/340 hp
" have a 1987 Merc. 454/340 hp bluewater inboard with 400 hrs. It had had a major tune up, plugs, cap, rotor,elec. points replaced (it has thunderbolt ing.) and a new carb. all filters have been changed.
Prior to the the above,the motor would seem to hit a wall at 3,300 RPM's in the past it would run up to 4,000 RPM's the same as the starboard motor. It it is still doing the same, hitting the wall at 3,300 RPM's, after the above parts replacements. The prop. has not hit anything and both props were "tuned" last season. The starboard motor runs up to the 4,000 RPM.
The engine in question does not burn oil, or does it have any valve train or bearing noise.
The boat is run in fresh water and has closed cooling. I also replaced the exhaust risers on the fresh water side on both motors this season. The motors run at normal operating temp.
Any thoughts on what to do next?
Thanks,
Mike "
" have a 1987 Merc. 454/340 hp bluewater inboard with 400 hrs. It had had a major tune up, plugs, cap, rotor,elec. points replaced (it has thunderbolt ing.) and a new carb. all filters have been changed.
Prior to the the above,the motor would seem to hit a wall at 3,300 RPM's in the past it would run up to 4,000 RPM's the same as the starboard motor. It it is still doing the same, hitting the wall at 3,300 RPM's, after the above parts replacements. The prop. has not hit anything and both props were "tuned" last season. The starboard motor runs up to the 4,000 RPM.
The engine in question does not burn oil, or does it have any valve train or bearing noise.
The boat is run in fresh water and has closed cooling. I also replaced the exhaust risers on the fresh water side on both motors this season. The motors run at normal operating temp.
Any thoughts on what to do next?
Thanks,
Mike "