FlaminFiero
Recruit
- Joined
- Aug 18, 2025
- Messages
- 1
Hello.
Here is the situation I am in. But before we go into it I have to list everything to know about my boat since there is a lot of weirdness surrounding it.
Known History.
1993 Renken 190BR
-Originally a 4.6 V6 with a 1.86 Volvo SX-M Outdrive.
-Previous Owner blew the 4.6 and partially installed a brand new 5.0FI Engine. Reused front lower engine mounts from V6 (Specifically the ones that are lag bolted to the stringers with the pair of nuts that raise and lower the outboard for alignment.)
-Drive was left outside disconnected, ujoints exposed. Engine was installed but holes for mounts not redrilled (Mounts connected to V8 now sit to far forward to meet the existing holes.)
It was at this point I acquire the Vessel.
-Redrill holes for forward engine mounts. Side to side alignment okay. Vertical Alignment impossible rear of engine WAY to high. I verified the rear mounts are installed correctly as per the service manual. Compensate by raising engine mounts to maximum extension, better but alignment still to high. Insert treated marine 2x4 between mounts and stringers. Increase lag bolt length to compensate. Lower Engine mounts almost all the way down. Fine Tune. Alignment is absolutely perfect. You can insert the Alignment tool with just one pinky finger and it spins with absolutely no resistance, I check this alignment every single time I pull the drive and it has not changed after almost 2 years and 10-12 outings.
Install 1.86 Drive. Take for test run. Vibrations on turns and a light somewhat random thumping noise at idle. Drive vibrations change with trim and turn settings.
Pull drive, replace gimbal bearing, gimbal bearing seal, inspect ujoints, the seem okay but the one closest to the drive feels slightly tighter than the rest. I operated the boat like this for a season since budget ran out and I have so little money into the boat (<$800 dollars) I don't care if it blows up. The conditions, nor vibration got any worse across 4-5 more outings.
After first test drive of year 2. A substantially worse vibration appears. I pulled the drive to find rear ujoint fully stuck. I was going to replace said ujoint when a correct 1.66 drive became available with new ujoints. Gimbal bearing still good, smooth and quiet, install new 1.66 drive with beautiful new joints.
Take test drive. No vibration, but somewhat random knocking noise still present at idle. no noise above idle in gear or when making a hard turn to port. These are the only conditions where the noise disappears. The knocking noise is IDENTICAL to the previous drive, the only change being it now disappears on hard port turns. Its very quiet buts gets slightly louder as the boat warms up. It sounds like someone tapping a block of aluminum softly against the transom from inside the bilge. I pulled the drive to inspect again. Bellows are dry, Ujoints are perfect and Gimbal bearing is perfect. Any ideas of what else this knocking noise could be?
Here is the situation I am in. But before we go into it I have to list everything to know about my boat since there is a lot of weirdness surrounding it.
Known History.
1993 Renken 190BR
-Originally a 4.6 V6 with a 1.86 Volvo SX-M Outdrive.
-Previous Owner blew the 4.6 and partially installed a brand new 5.0FI Engine. Reused front lower engine mounts from V6 (Specifically the ones that are lag bolted to the stringers with the pair of nuts that raise and lower the outboard for alignment.)
-Drive was left outside disconnected, ujoints exposed. Engine was installed but holes for mounts not redrilled (Mounts connected to V8 now sit to far forward to meet the existing holes.)
It was at this point I acquire the Vessel.
-Redrill holes for forward engine mounts. Side to side alignment okay. Vertical Alignment impossible rear of engine WAY to high. I verified the rear mounts are installed correctly as per the service manual. Compensate by raising engine mounts to maximum extension, better but alignment still to high. Insert treated marine 2x4 between mounts and stringers. Increase lag bolt length to compensate. Lower Engine mounts almost all the way down. Fine Tune. Alignment is absolutely perfect. You can insert the Alignment tool with just one pinky finger and it spins with absolutely no resistance, I check this alignment every single time I pull the drive and it has not changed after almost 2 years and 10-12 outings.
Install 1.86 Drive. Take for test run. Vibrations on turns and a light somewhat random thumping noise at idle. Drive vibrations change with trim and turn settings.
Pull drive, replace gimbal bearing, gimbal bearing seal, inspect ujoints, the seem okay but the one closest to the drive feels slightly tighter than the rest. I operated the boat like this for a season since budget ran out and I have so little money into the boat (<$800 dollars) I don't care if it blows up. The conditions, nor vibration got any worse across 4-5 more outings.
After first test drive of year 2. A substantially worse vibration appears. I pulled the drive to find rear ujoint fully stuck. I was going to replace said ujoint when a correct 1.66 drive became available with new ujoints. Gimbal bearing still good, smooth and quiet, install new 1.66 drive with beautiful new joints.
Take test drive. No vibration, but somewhat random knocking noise still present at idle. no noise above idle in gear or when making a hard turn to port. These are the only conditions where the noise disappears. The knocking noise is IDENTICAL to the previous drive, the only change being it now disappears on hard port turns. Its very quiet buts gets slightly louder as the boat warms up. It sounds like someone tapping a block of aluminum softly against the transom from inside the bilge. I pulled the drive to inspect again. Bellows are dry, Ujoints are perfect and Gimbal bearing is perfect. Any ideas of what else this knocking noise could be?
