Pulled off Anode from Gimbal Housing & this fell out!!

[Craig W]

Hi All,

think of this as one of them "identify the tool" type contests (except I think its a part from somewhere in the outdrive)

Hoping maybe someone can shed some light here... Doing routine maintenance, just cleaning stuff up and tinkering around my 1998 Volvo SX outdrive (attached to a 3.0L). Took the anode from the gimbal housing (to clean the zebra muscles from the anode) and a small "shaft" fell out. It was in there loose and I have no idea where it may belong/come from. 3 1/2" long, about 1/8" diameter, chamfered ends and appears to be stainless steel. Has wear patterns on it like it might have been a "hinge or pivot pin" of some sort. Hope this photo might help explain more.



I'm completely at a loss... Any help to find where it should be is appreciated. Even if you can make suggestions for possible applications and I can check to see. I'm not use to having "extra pieces" left over!! Wondering if it might have been one of those "crap! I dropped it... now where the frig did it go??!" type pieces from someone else (a prior owner) when having service done and just never found it (but hopefully replaced it... )

 

[Don S]

Re: Pulled off Anode from Gimbal Housing & this fell out!!

It was the pivot pin for the exhaust shutters. Would bet money you find the rest in the drive or the exhaust tube. You need to pull the drive to check. You should also be pulling the drive yearly for other maintenance as well. Do you?

 

[Craig W]

Re: Pulled off Anode from Gimbal Housing & this fell out!!

Thanks for the quick reply Don S. You are the best!

I just had the drive off to check the bellows and grease the gimbal bearing. Everything looked ok in there, and put it back on last week.

Exhaust shutters? Didn't even realize there was such a thing on an I/O. Is it likely that I caused it to drop out by not paying attention (not knowing it was there) when I removed the drive? I've searched the SX/DP ver2003 PDF manual and the there "exhaust shutters" doesn't find anything. Is there any terminology that I can narrow down in the manual look through before pulling things apart? Or is this a matter to put my "intuitive hat" on first and just start pulling bolts!?

EDIT: just found the description in the -BY- Engine manual PDF under "exhaust flapper valve" page 3-39. Guess I've got some stuff to pull off and check now.

Thanks for pointing me in the right direction Don. I'll hopefully have results to post in a day or two.

BTW: is this something that can just "fall off"??

 

[Don S]

Re: Pulled off Anode from Gimbal Housing & this fell out!!

If you didn't find the parts when you had it before, it may be inside the exhaust passages in the outdrive. Pull the prop and look in that direction too.
One other note, Volvo stopped using the shutters, here is the service bulletin containing the change.

http://www.4shared.com/document/bgV6659D/Volvo_Exhaust_Flapper_valves.html

 

[Craig W]

Re: Pulled off Anode from Gimbal Housing & this fell out!!

Hi Don,

I have the outdrive off and have looked into the passages on the outdrive. If I'm understanding the service manual, and the tech bulletin (you posted above) the only part(s) small enough to make it to the outdrive would have been the rubber bushings on the side or any bits from busted tabs on the flapper valve. I can't find anything in the outdrive. It's likely they may/would have passed straight through the exhaust?

Its mentioning that the flapper valve can block the exhaust. From looking at the gimbal housing (toward the stern-photo below) the passage into the outdrive doesn't look big enough to pass the flapper through.



How big is the flapper? Judging by the shaft and the exhaust opening where it's supposed to be would it be around 3" dia?

Is it more likely that the flapper is lodged into the bottom of the riser in the engine bay? (photo below)



I have one of those flexible finger grippers (that has 4 wire prongs that extend out to grip when the button is pushed on the top) and have been poking around inside the riser. I think something might be down in there, but it transitions 90deg toward the center of the boat and I can't seem to grip anything. Is this flapper aluminum? or would I be in luck and it's made out of ferrous steel and be attracted to a magnet? Have you (or anyone reading this) run into this problem and found a way to get the flapper out? (really wish I had one of them scopes right now.. the mirror and light just won't work.. I'm fishing blind)

Thanks for any insights in advance...

 

[jze1212]

Re: Pulled off Anode from Gimbal Housing & this fell out!!

I would say the flapper is stuck in your down pipe somewhere, maybe try to push it back up from the outside of the exhaust tube going back up? I bet a small shop vac tube would fit up there and push that sucker right out ( assuming you have the risers off, which you do in the picture.. )

 

[Craig W]

Re: Pulled off Anode from Gimbal Housing & this fell out!!

Thanks jze1212, I spent the better part of an hour with a coat hanger, electrical "fish tape" and a couple other flexible implements to feel around in the exhaust down from the riser and up from the transom. Couldn't feel any blockage or dislodge anything, so I'm having to accept it may have been removed by a prior owner/mechanic but the shaft must have been dropped in the process. I guess if I ever run into a stalling problem I'll know the first place to look!

 

[CharlieB]

Re: Pulled off Anode from Gimbal Housing & this fell out!!

Unfortunately, if that piece IS still in there, and moves and begins to restrict exhaust flow, it can cause excessive backpressure, overheating the motor.

With the outdrive off, use a mechanics extendable mirror and small flashlight, reach in thru the exhaust to look around the corner for the flapper pieces.

You really want to be SURE they are out of there.