Knocking in rear??? [Archive] - The Donzi Registry

JimG205

12-27-2005, 06:09 PM

While winterizing the minx in the driveway,I could hear a distinct knocking that was coming from the transom area between the mtr and outdrive unit,while in neutral.I know there's a universal joint in there,how hard is it to remove and install a new one???:bonk:

MOP

12-27-2005, 06:12 PM

While winterizing the minx in the driveway,I could hear a distinct knocking that was coming from the transom area between the mtr and outdrive unit,while in neutral.I know there's a universal joint in there,how hard is it to remove and install a new one???:bonk:

Pull the drive it is right there looking at you! It is about the same job as changing Ujoints in a cars drive shaft.

Phil

Jim just thinking, you have a Volvo Yes? If so things are a bit different.

mrfixxall

12-27-2005, 07:50 PM

While winterizing the minx in the driveway,I could hear a distinct knocking that was coming from the transom area between the mtr and outdrive unit,while in neutral.I know there's a universal joint in there,how hard is it to remove and install a new one???:bonk:

If its a volvo,,,,,mine has been making noise for years...
its the springs on the vibration damper on the flywheel that connects to the drive shaft.i was concerned about the noise and replaced it and the noise was still their.I replaced all the u joints,inner and outter bearings and seals in the housing and the noise was still their so i guess it's normal.Installing new u joints was a piece of cake...

Tony

12-27-2005, 08:36 PM

My Volvo makes the same noise, and has for years.
It is great to finally have it explained...thanks Mr. Fixxall !

gcarter

12-27-2005, 08:51 PM

Minx's came with Alphas.......my joints were getting noisy before I changed the drive.

JimG205

12-28-2005, 07:23 AM

Drive is an Alpha one.Thanks George-should have been more specific.:cistineb:

MOP

12-28-2005, 10:20 AM

Jim back to plan A pull it, I know you are handy enough to do a U joint job. If the U joint is appears tight and in good condition bad alignment can make a fairly loud dull knock. Stick the tool in and check that out.

Phil

mrfixxall

12-28-2005, 10:24 AM

Drive is an Alpha one.Thanks George-should have been more specific.:cistineb:

Do you have a y pipe? It could be the exhaust flappers in the y pipe,their are rubber ends on the flappers that burn off after time and they make a lite knocking noise in the y pipe...

EricG

12-28-2005, 10:32 AM

Minx's came with Alphas.......my joints were getting noisy before I changed the drive.

I realize it doesn't apply to Jim's drive - but there is at least 1 Minx running around out here with a Volvo 280/290 on it. Unfortunately I didn't get a chance to look at the hull # when I ran into him at the gas station a few years back. It might have been the boat that wrecked last year...

We now return you to our regularly scheduled Alpha :rolleyes: :biggrin.:

EG

MOP

12-28-2005, 10:42 AM

Jim is it a fairly loud not consistant clicking or a consistant dull thuddy sounding know that will tell you which it is. Still I would pull the drive and check all the normal stuff, bellows, U joints, gimble bearing for smoothness and last but most important alignment.

Phil

Rootsy

12-28-2005, 10:57 AM

if it's a U-joint knocking it should quiet down when you turn the sterndrive side to side... wouldn;'t hurt to pop the top cap and give the gears a look either... take a tooth off and it'll sound like the engine is coming apart on you...

MOP

12-28-2005, 11:21 AM

Just spoke with Jim due to my expiring memory I forgot he is running his exhaust straight out no Y. He has not checked alignment since he bought the boat, it had a new just installed engine so good chance it needs a little massaging. He is going to tear into it check what is causing the noise and while he is at it he is finally going to put his Silent Choice setup on it. And another Project starts!!!

Good luck with it!

Phil

mattyboy

12-28-2005, 11:44 AM

if it's a U-joint knocking it should quiet down when you turn the sterndrive side to side... wouldn;'t hurt to pop the top cap and give the gears a look either... take a tooth off and it'll sound like the engine is coming apart on you...

Amen Brother

mikev

12-28-2005, 12:26 PM

Question was the drive trimmed all the way up? because my alpha i knocks like that when its on the trailer with the drive up you put it down some and it is quiet as can be.

JimG205

12-28-2005, 08:58 PM

After a brainstorming session with MOP on the phone today,I have a plan-the Minx is my first venture into I/O's,having been a direct drive inboard guy my entire life.To all who answered-Thanks.To those who may be afraid to ask for help-DON'T BE-there is an abundance of knowledge and experience second to none on the Donzi Registry.:beer:

mrfixxall

12-28-2005, 10:30 PM

Question was the drive trimmed all the way up? because my alpha i knocks like that when its on the trailer with the drive up you put it down some and it is quiet as can be.

Thats a big no!no!..only start the engine when the trim is registering on the trim guage..the noise your hearing is the ujoints binding and could cause alot of damage to the ujoints,yokes and could rupture the bellows..:eek!:

Rootsy

12-29-2005, 06:28 AM

actually, according to mercruiser directly from the #6 manual and the owners manuals they send out with the I/O's it is Fine to start and run the motor with the sterndrive in the trailer position. BUT ONLY AT IDLE... because as you said mrfixall, it'll damage the u-joints and gimble due to the extreme angles and loading that occurs when in the trailer position. I still drop it as much as i can to start and warm up, but sometimes i must idle out in the trailer position or very close to it due to shallow water...