Hello all, I am having a noise that I cannot diagnose from what I believe is my outdrive. It is a DP-SM, p/n 386-8913 w/ transom asbly SX-MBAC, behind a 5.7 GXi-F (2005 Larson 248 LXi). Attached is a link to a audio/video file that I made today on a cold start of the engine. Boat had been sitting for about 5 days. This noise started this season after drive maintenance was done, but I didn't hear it in the driveway on the hose after putting everything back together (was started 2-3 times at home before going back to the lake) but the exhaust noise is much louder on the hose.
This noise is only on cold start. In the video, the drive is in full down position, boat sitting in the marina. Turning the steering wheel makes to change to the sound. It will last for about 90 seconds, then it is gone and will not recur till another cold start. Engine and drive run great, no other noises, issues, etc.
Drive maintenance this year:
New OEM bellows
New Sierra greaseable gimbal (these were replaced due to the bellows leaking last year). Gimbal was aligned by hitting w/ dead blow hammer x4 directions per manual
Ujoints were inspected and I could find no roughness/etc in any of the spiders.
Alignment checked, and ok as far as I could tell (tool went in and out very easily, and spline marks all around nose, but slightly heavier on one side than other)
Replaced outdrive oil w/ VP synthetic. The old oil was not milky, but not honey brown either, a bit grey, and I think there may have been a small amount of water in it in emulsion, but none visible when drained (not much as the oil level before draining was still normal). Oil level is at the top of the flat section of the dipstick. I've checked this x several, after running the drive.
Drive was pressure and vacuum tested at low and high pressure/vacuum per the factory service manual. passed w/ flying colors.
Drive repainted this spring as well.
Engine maintenance is up to date, w/ this year getting new VP rotor/cap/wires, and AC Delco iridium plugs that cross reference to OEMs.
The only incident from launch (where I didn't notice the noise) to when I did, was hitting a branch probably about 1.5" in diameter at appx 35mph. Dead centered it, from the paint scratches (on the newly repainted drive!) it appears the drive split the stick. no damage to the metal on inspection, no leaks, etc. props have no dings, etc.
Finally, just as an example of use today, to escape some T storms, we ran hard about 6 or so miles (small lake). about 50mph at 4800 RPM the whole way, and didn't miss a beat, not a single issue. This was after a few hours of tubing and skiing. No abnormal noises at all after the startup.
Help!
This noise is only on cold start. In the video, the drive is in full down position, boat sitting in the marina. Turning the steering wheel makes to change to the sound. It will last for about 90 seconds, then it is gone and will not recur till another cold start. Engine and drive run great, no other noises, issues, etc.
Drive maintenance this year:
New OEM bellows
New Sierra greaseable gimbal (these were replaced due to the bellows leaking last year). Gimbal was aligned by hitting w/ dead blow hammer x4 directions per manual
Ujoints were inspected and I could find no roughness/etc in any of the spiders.
Alignment checked, and ok as far as I could tell (tool went in and out very easily, and spline marks all around nose, but slightly heavier on one side than other)
Replaced outdrive oil w/ VP synthetic. The old oil was not milky, but not honey brown either, a bit grey, and I think there may have been a small amount of water in it in emulsion, but none visible when drained (not much as the oil level before draining was still normal). Oil level is at the top of the flat section of the dipstick. I've checked this x several, after running the drive.
Drive was pressure and vacuum tested at low and high pressure/vacuum per the factory service manual. passed w/ flying colors.
Drive repainted this spring as well.
Engine maintenance is up to date, w/ this year getting new VP rotor/cap/wires, and AC Delco iridium plugs that cross reference to OEMs.
The only incident from launch (where I didn't notice the noise) to when I did, was hitting a branch probably about 1.5" in diameter at appx 35mph. Dead centered it, from the paint scratches (on the newly repainted drive!) it appears the drive split the stick. no damage to the metal on inspection, no leaks, etc. props have no dings, etc.
Finally, just as an example of use today, to escape some T storms, we ran hard about 6 or so miles (small lake). about 50mph at 4800 RPM the whole way, and didn't miss a beat, not a single issue. This was after a few hours of tubing and skiing. No abnormal noises at all after the startup.
Help!
