Duo prop seal replacement

mtboatin

Petty Officer 2nd Class
Joined
Jul 27, 2012
Messages
167
Hi all. I have a dp-d1 I believe which is new to me this past summer. Finding lower unit oil looking a little milky even after changing it and only running it about five afternoons.

I finally got around to pressure testing and at 3lbs. held fine at 10 min. I took the pressure up to 10lbs. and it dropped on 1lbs. in 10 min. while intermittently spinning the prop by hand. Pulled props and found a leak at the front shaft seal (toward front of boat). I believe part # 851407.

I'm looking for any how to info on replacing this. I did some searching on line and watched a few videos that made me question their technique. Also any recommendations on related items, ie. is there a better seal available that I should consider, special tools required, or any other related parts recommended.

The lower unit is on a 725 hr 1994 Cobalt that was supposedly out of the water unused for 3-4 years prior to purchase. It had also had the lower unit removed and sent out for a complete overhaul in 2017 (gears, bearing and related and I saw the receipt). PO claimed it only had approx an hour run time on it since ( not sure how accurate that is). Seal in question has lower unit paint on it for what it's worth.

Prior to pressure test I called a local shop and talked to their tech. He made a commented that 70% of the old duo props he sees has a leaking billows that will allow water into the lower unit as a result. I'm not sure I follow his info.
 

Attachments

  • 20210528_104022.jpg
    20210528_104022.jpg
    7.9 MB · Views: 5

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
50,319
You should pull the drive and pressure test

Easy drives to reseal
 

mtboatin

Petty Officer 2nd Class
Joined
Jul 27, 2012
Messages
167
Scott. Can you give me any direction on lower unit removal? Unable to find a manual. Also a list of recommended replacement parts and things to check while off? Found a couple of videos that doesn't make it look too difficult.

Other than prop removal and purchasing and installing missing thrust washers, along with new washers and o rings for the three plugs, and new fluid, I have yet to preform any other maintenance.
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
50,319
Google volvopenta manuals and you get to the manuals website

Pm me your email and I can send a DP A manual

Go to volvopentastore.com and look up seal kits
 

dypcdiver

Lieutenant Junior Grade
Joined
Nov 1, 2005
Messages
1,040
This is a DP-SM, be prepared to use some force!
 

Attachments

  • 20190520_183655.jpg
    20190520_183655.jpg
    3 MB · Views: 30

mtboatin

Petty Officer 2nd Class
Joined
Jul 27, 2012
Messages
167
This is a DP-SM, be prepared to use some force!
Whoa! I was thinking this was a seal that would be pried out or drill and run some screws in to push out. Here's to hoping my d1 is set up different to a sm!
 

mtboatin

Petty Officer 2nd Class
Joined
Jul 27, 2012
Messages
167
Got on volvopentastore.com and sight is not great to navigate or get descriptions. If I am correct, the seal kit I need for a dp-d1 is https://www.volvopentastore.com/Gas...on_id.129158069--store_id.366--view_id.305751

It gives no info on what is included. I would assume all the seals necessary? When looking at individual seals some say "through dealer" or "out of stock". Are these seals still part of the seal kit?
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
50,319
Got on volvopentastore.com and sight is not great to navigate or get descriptions. If I am correct, the seal kit I need for a dp-d1 is https://www.volvopentastore.com/Gas...on_id.129158069--store_id.366--view_id.305751

It gives no info on what is included. I would assume all the seals necessary? When looking at individual seals some say "through dealer" or "out of stock". Are these seals still part of the seal kit?
get the part number of the seal kit, then google it. I picked up some from iboats in the past as well as amazon for less money.

regarding the D1 lower, its nothing like the SM. biggest tool you may need is a deadblow hammer.
 

mtboatin

Petty Officer 2nd Class
Joined
Jul 27, 2012
Messages
167
I'm just not sure this 876266 is the kit I needed. It's States DP - D1. But when I punch that number into Google on certain sites it shows as possible upper unit kit. Which I may need as well. I don't know.

Here is another page that has a break down of parts but shows no "kit".
 

mtboatin

Petty Officer 2nd Class
Joined
Jul 27, 2012
Messages
167
Ok. I may have made some headway. I believe the top kit is the and the 876266 bottom is the 876267.

Am I correct in assuming I'll need both kits to perform a reseal?
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
50,319
Ok. I may have made some headway. I believe the top kit is the and the 876266 bottom is the 876267.

Am I correct in assuming I'll need both kits to perform a reseal?
yes, two kits
 

mtboatin

Petty Officer 2nd Class
Joined
Jul 27, 2012
Messages
167
I built a lower unit holder out of a Harbor Freight moving dolly and some 2xs. Just got the lower unit out and in the garage for the winter service. Both anodes, billows kit, rubber exhaust flap, and seal kits on the way.

What other items are recommended to be inspected and or serviced at this time?
 

Attachments

  • 20211110_185520[1].jpg
    20211110_185520[1].jpg
    1.4 MB · Views: 9
  • 20211110_185507[1].jpg
    20211110_185507[1].jpg
    1.1 MB · Views: 8

mtboatin

Petty Officer 2nd Class
Joined
Jul 27, 2012
Messages
167
Finally received all my seals. Can anyone verify if any specialized tools are required before I start disassembly?
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
50,319
Finally received all my seals. Can anyone verify if any specialized tools are required before I start disassembly?
VP shop manual
method to read rolling torque

did you get a new crush sleeve for the input shaft, or are you not replacing the input seal?
 

mtboatin

Petty Officer 2nd Class
Joined
Jul 27, 2012
Messages
167
Newbie to this. I bought an upper and lower seal kit thinking I would reseal the whole thing. It has been rebuilt before pretty extensively in 2017. Some gears replaced as part of it. PO claims it didn't have much run time on it but I have no way to verify that. You were kind enough to send me a copy of the manual. Not familiar with the crush sleeve. So what you're saying is to do the input seal requires a new crush sleeve? Also may need some verification on what rolling torque is. I have a few different torque wrenches. I've never run into rolling torque prior to this.
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
50,319
Yes, to replace the input seal, you should have a new crush sleeve to set bearing pre-load correctly
 
Top