Volvo DP-SM Shift Seal

DougP121

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Joined
Mar 12, 2011
Messages
6
After hauling out boat for season I noticed a leak from under the shift cover on the drive.

After some investigation the seal ring portion of the shift mechanism is leaking. The SELOC repair manual says after seal replacement and reassembly to shim the piston by using "special bracket (#3850057)".

I have not been able to locate the bracket except in the SELOC and a few other manuals online. Similar to thread below. Does anybody have any ideas on where to get the bracket or if not available how to adjust shims on shift assembly piston screw without it?

I plan on replacing the o ring and seal assembling and then checking pressure and vacuum.


From previous thread_______________________

"... Need help with Volvo SX-C shift cam shimming ??
I was checking out the boat yesterday and discovered gear oil leaking from under the shifter cover. I removed the cover and saw the oil was leaking from the shift cam seal. The whole thing looked really corroded and old. When I drained the oil it was NOT white or milky at all. Looked used but not bad. Opened my manual and went to work on it. I followed the directions and repleced the seal and the O ring. I cleaned everything up really well and put it all back together. My issue is with shimming the cam.The manual is saying I need a "special bracket #3850057"I have looked online and have not been able to locate this "special bracket". Assuming that it was shimmed correctly before, I tried to run it and it will go into forward, neutral, but not reverse? I shut it down and backed the cam bolt out so it is loose and that is where I stand at the time. Is there a certain position the shifter cam needs to be in before I tighten the bolt?? Thanks

Drive info:
Volvo Penta SX-C 1.66
3868160
4112012518
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July 20th, 2011,*01:12 PM #2
Don S
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Re: Need help with Volvo SX-C shift cam shimming ??
If you didn't replace anything but seals, you do not have to reshim that part. Only if you replace the whole shift mechanism or shift shoe, or cone.

Did you put the shift mechanism back in with the shift shoe offset to the starboard side?
 

HorizonblueDK

Petty Officer 1st Class
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May 27, 2010
Messages
355
Re: Volvo DP-SM Shift Seal

I have never shimmed the shoe with the bracket.

When rotating the shift arm, you will notice that it goes in and out of the housing, as you rotate it. Place it at the angle where it sits deepest in the housing. This is where it must be shimmed.

It can be rotated a few degrees, when it is at the deepest point.

I believe that the bracket holds the arm in this position, where it sits deepest.
 

billbayliner

Chief Petty Officer
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Jun 30, 2006
Messages
553
Re: Volvo DP-SM Shift Seal

You are just going to remove the seal housing with the 4 bolts.

Pull the shoe (Part # 3856502) and spring from the eccentric piston (3856008) (brass and is what the shift cable / rod connects to)

You will now push the spring pin (973593) INTO the eccentric piston

The pin that slides in and out of the housing grooves will now pull out.

Once out the eccentric piston will now slide out of the housing.

You now have access to the seal.

NO SHIMMING IS REQUIRED AS YOU WILL NOT HAVE TAKEN screw 897711 out of the exterior side of the eccentric piston. IF you have removed the screw then make sure to put some permatex or loctite aviation sealant on the treads before screwing back in.

BE CAREFUL not to lose that spring pin that is in the eccentric piston bore hole. To get it out spray some WD-40 into the hole and it will slide out. Be sure to use a proper sized flat punch when tapping the spring pin in so not to damage it. I personally use a smaller size spring pin.

YOU HAVE Got to make sure that the dog goes back into the sliding sleeve (some people call it the cone) in the correct direction. Not when you are taking out.

ONE OTHER THING: on the grooves of the inner part of the seal housing that the pin move on and into, file any deformities out as this will cause shifting stiffness. I also turn the sliding pin to the opposite side when I put the pin in the eccentric piston thus now having the non worn side being used.

Hope this helps

Bill


BTW ........... Quit using that Seloc manual. There are digital Volvo shop manuals available in our info section
 
Last edited:

jerryjerry05

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May 7, 2008
Messages
17,924
Re: Volvo DP-SM Shift Seal

Do not mess with the factory shim values.... unless a shift shoe has been changed.



The brass unit is an "eccentric piston".

And yes.... due to the detent pin and it's cam, the eccentric piston is supposed to move inward and outward as it is operated.



the piston seal surface needs to be polished highly as to prevent new seal damage or leakage.

Also.... these seals are directional.



Very important note for any eccentric piston whereby the spring pin is parallel with the piston:



When the Neutral/FWD/REV detent pin "spring pin" is pushed inwards (as to release the detent pin) it must be retrieved.

If this spring pin is NOT retrieved, you'll have great difficulty when trying to remove the detent pin (prior to installing another eccentric piston seal) in the future.

This pin must be retrieved.

Carburetor cleaner will reduce the oil viscosity and will help it fall out.
 

DougP121

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Joined
Mar 12, 2011
Messages
6
Re: Volvo DP-SM Shift Seal

Thanks for all you inputs.

Pressed the new seal in today (a bit difficult without a press but got it in). Pressure and Vacuum tested both held. Before the replacement could not even pressurize as the seal was clearly leaking.

Question -

1 - should I let the drive continue to drip - a few drips an hour at most of gear oil is all that is coming out,

2 - refill with new Volvo gear oil,

3 - do anything else to clean out whatever remains from the leaky oil and assumed some water from the drive?

(note already drained once and filled with new volvo gear oil at end of season. I did that first oil change before i just drained again (this weekend) to replace the shift seal. It is interesting that the gear oil from the marina work last year was green and the volvo gear oil is clear/amber but the new volvo oil i had put in a few weeks ago came out greenish - i believe that must be due to residual "green oil" that remained on the gears and such after the initial season ending gear oil change)

Thanks again for your inputs.
 

billbayliner

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Jun 30, 2006
Messages
553
Re: Volvo DP-SM Shift Seal

There cannot be that much residue left. If you are worried hook some compressed air to the top and keep the drain open and open up the air and force it out.

Then fill with some fully synthetic gear oil and have fun.

Also.... these seals are directional.

Excellent call on adding this very important information above Jerry. I should have had that in my post above.
 
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