DP-A vs DP-B Upper Gearbox

[woodword]

As discussed in earlier threads, we have what we believe is a DP-A hooked to a AQAD-41B engine. It is slipping out of and hesitant to go into forward gear at low RPMs and we believe we need a rebuilt upper gearbox. I found a DP-B rebuild and want to confirm it will work with our setup. The rebuilt came from an outdrive with serial number 3102092779 [FONT=&quot]and our outdrive serial number is [/FONT] [FONT=&quot]3102093409. These numbers are very close so I am assuming this gearbox will work.[/FONT] They are asking $1300 for the unit including new u-joints and will give us $200 for our core. This is the item description:

"Up for sale is an excellent condition Rebuilt , Resealed , Volvo Penta DP-B upper gear unit , This unit was completely dis assembled , cleaned and inspected , New Seals official Volvo Penta only, No Aftermarket Junk. Every gear is perfect , every bearing spins flawlessly, No Pitting what so ever, No rust or corrosion , all housing components were lightly sanded , Primed with Zinc Chromate Primer , a fresh Coat of Volvo Penta Aquamatic White was applied , and then clear coated to add durability to the finish, I replaced the u-joints with top quality Forged MOOG , U.S.A built Universal Joints. This unit was originally mated to a Dp-B with 1.78 gear ratio for high torque and horsepower Big block and diesel applications tagged 854298 (Outdrive Part Number) 3102092779 (serial Number) this is interchangeable with All gear ratios , Dp-A Sp-A 290A Dp290 and others This unit is Ready to go . Bolt it on get Back in the Water!"

Thanks for your expert advice!

 

[captmello]

I think that upper will work just fine, however "Bolt it on and get back on the water" is bad advise since the new gear box will need to be shimmed to fit your outdrive.

 

[Scott Danforth]

Captmello, are you sure about shimming needed? the only thing below the upper transmission is the splined sleeve running to the lower shaft and the o-ring. the gear box is where all the shimming, crush washers, etc. happens

 

[captmello]

Well...I thought they all were shimmed under the upper, My 275 is...I'll have to do some more research.

 

[captmello]

So, I checked the parts breakdown, and in this link for the DP-A, it shows the shims as at #36

Page 122 in the manual describes it.

http://www.volvopentastore.com/Inter...view_id.785768

 

[woodword]

Hey guys, thanks for the input. I have another question. When I pull the malfunctioning upper off our DP-A, can't I just use the same shim?

 

[captmello]

Hey guys, thanks for the input. I have another question. When I pull the malfunctioning upper off our DP-A, can't I just use the same shim?

No, because the castings vary. The shimming procedure doesn't look to tough, although I've never done it.

 

[woodword]

It looks like a matter of having the right measuring tool. Hopefully, I can get my hands on such a tool. I have a measuring device but will have to take a look to see if it will work. Gotta love the Volvos, sheesh...

 

[captmello]

tight tolerances =low wear = long life.

Do it right the first time.

 

[billbayliner]

A DP-B upper WILL NOT work on a DP-A. There was a bearing change PLUS many other things from the A to the A1. Then in the A2 there was a gear set change.

 

[billbayliner]

As for the DP-A not going into gear... Is the Engine RPM at the proper setting? Can be more than that but that's a start. When I rebuild these I find that most of the time it is glazing on the sliding sleeve and cups from people using traditional oil in the DP's instead of FULLY synthetic. I can tell even by the smell when I open them.

 

[captmello]

A DP-B upper WILL NOT work on a DP-A. There was a bearing change PLUS many other things from the A to the A1. Then in the A2 there was a gear set change.

thanks for checking in Bill, don't be a stranger.

 

[woodword]

According to my Volvo guy, the DP-C has a different bearing. The DP-B upper will mate with the DP-A housing. I guess will find out in 6 weeks when I take it up to Kodiak, AK to install it.