AngryPossum
New Member
- Apr 27, 2023
- 7
- Boat Info
- 1985 Century Mustang II
- Engines
- Mercruiser 3.0
I ran it w the drive off no difference. Gonna do a compression test and timing Friday. See what I come up with.
Noise From Rear of engine At Outdrive.
- Thread starter Michaelbluewolf
- Start date
Soulshine
Well-Known Member
Hmm...that's sucks.
Since you have the drive off and no visible flappers, look into the bottom of the exhaust pipe where it mates with the drive. Failed flapper parts land there and can create overheating. Odds are that they were never put back in.
While you have the plugs out doing the compression test, spin the motor over with the starter and see if you hear that knock.
Good luck.
Since you have the drive off and no visible flappers, look into the bottom of the exhaust pipe where it mates with the drive. Failed flapper parts land there and can create overheating. Odds are that they were never put back in.
While you have the plugs out doing the compression test, spin the motor over with the starter and see if you hear that knock.
Good luck.
scoflaw
Well-Known Member
- Aug 10, 2011
- 6,395
- Boat Info
- 1999 Powerquest legend 260 sx 502 mag
2005 Baja 242 islander 496
- Engines
- 502 mpi Bravo 1
496 mag B1
Something big is loose. Flywheel, starter, harmonic balancer.
TWorline
New Member
11 years between post #11 & post 12....took quite a while to get a camera! A couple of thoughts about why the outdrive went on hard: 1. Check the driveshaft length to make sure it is not to long. 2. . Check the big o-ring to make sure it did not get pinched during the install.
AngryPossum
New Member
- Apr 27, 2023
- 7
- Boat Info
- 1985 Century Mustang II
- Engines
- Mercruiser 3.0
Ok, so the issue I had was the engine coupler. The outdrive,,, because it wasn't aligned properly to the coupler,, had created extreme pressure/inertia and compromised the coupler, causing the coupler to basically stress with the coupler bolts and flywheel..
We finally removed the engine and found the loose coupler bolts. Later, when we went to re-mount the sterndrive, we simply couldn't, because the alignment was over 1/2 un-aligned, and the engine then needed to be raised. This without any doubt caused the coupler damage.
So, Always always, check your engine alignment. It's so critical and can save you thousands and even your boat.
Here's my actual video of the sound I had. You can hear that coupler clanging away like a bell.
https://youtube.com/shorts/ejTgRw6c_rQ?feature=share3
We finally removed the engine and found the loose coupler bolts. Later, when we went to re-mount the sterndrive, we simply couldn't, because the alignment was over 1/2 un-aligned, and the engine then needed to be raised. This without any doubt caused the coupler damage.
So, Always always, check your engine alignment. It's so critical and can save you thousands and even your boat.
Here's my actual video of the sound I had. You can hear that coupler clanging away like a bell.
https://youtube.com/shorts/ejTgRw6c_rQ?feature=share3
