Volvo 280 duoprop ? UPDATED with install and sea trial.

[mtnrat]

I have 280 DP lower that I want to put on my SP 280. Here are a couple of pictures of the unit I have. looks like I need on this part:

The lockwasher for the forward propeller nut.
And on the driveshaft the:

Shim material; spacer ring and lockwasher.
Am I correct in this evaluation? If so what are the part numbers for those?

 

[Don S]

Re: Volvo 280 duoprop ?

Re: Volvo 280 duoprop ?

Top picture. No lock waters under the prop nut.

Lower picture. Where is the bearing race for that bearing? You don't want to just stick that bearing into the race from your single prop drive. The bearings are different
You do need to shim the bearing race. Go to page 120 of the OEM service manual for how to shim the race.
If you don't have the manual, you can download it at the link below.
http://www.4shared.com/account/file/48536730/fa3b3311/280_to_DP-C_Drive_manual.html

 

[mtnrat]

Re: Volvo 280 duoprop ?

Re: Volvo 280 duoprop ?

So in this diagram I would need numbers 17, 18 ,19 and 20 with 17 being the bearing and race?

 

[Don S]

Re: Volvo 280 duoprop ?

Re: Volvo 280 duoprop ?

You might want to get the original bearing race since to replace that bearing, you have to completely dissassemble the lower unit. That bearing (#17) is pressed onto the shaft.

 

[mtnrat]

Re: Volvo 280 duoprop ?

Re: Volvo 280 duoprop ?

That is not good as I do not know if I will be able to get it, but I will try.
Thanks for the info.

 

[mtnrat]

Re: Volvo 280 duoprop ?

Re: Volvo 280 duoprop ?

Not having any luck with the old race, and I believe that a new race is incompatible with a used bearing. There are a lot of special tools involved with installing a new bearing, so the cost of tools is quite high. How many hours would a volvo mech need to change the bearing, and if that bearing is being changed what else should be done at the same time?

 

[Don S]

Re: Volvo 280 duoprop ?

Re: Volvo 280 duoprop ?

I would sure put new seals in it, but it wouldn't be necessary to reshim anything as you would only be replacing that one bearing. New nut on the pinion gear and a check of the backlash and rolling torque. (which should be done before taking it apart to make sure nothing changes during the reseal)
1.5 to 2 hours max should do it unless the backlash and RT are way off to start with. Plus the price of the seal kit.

 

[mtnrat]

Re: Volvo 280 duoprop ?

Re: Volvo 280 duoprop ?

Took in the duoprop and had a new bearing and race installed, new seal kit. The mech checked all shimming, the gear pattern, the rolling torque etc. I am now good to go with the install. Tonight I did a quick check of the shimming needed between the lower and intermediate. Looks to be the same as the original. Whoda thunk. I will double check again in the morning with better light.

 

[Don S]

Re: Volvo 280 duoprop ?

Re: Volvo 280 duoprop ?

You do realize that my information was not free, now, you are REQUIRED to report back on how much different the DP is over the SP after you get it installed and proped correctly.

 

[Maclin]

Re: Volvo 280 duoprop ?

Re: Volvo 280 duoprop ?

it is a moral imperative

 

[mtnrat]

Re: Volvo 280 duoprop ?

Re: Volvo 280 duoprop ?

lol, Will give complete sea test sunday or monday.

 

[mtnrat]

Re: Volvo 280 duoprop ?

Re: Volvo 280 duoprop ?

Took it out for 3 hours this morning. Holy hole shot Batman! Like instantaneous. I had to put the trim bolt in the rear hole, as in the middle hole the bow was being pushed into the water. That worked great. Now just a very little use of the trim tabs are needed. Acceleration is excellent. Reverse is predictable and straight. I cannot believe how much better the boat handles. Almost no loss of speed when turning, although that may have a little to do with the torque of the 383.
The best thing is I no longer get prop torque at 4000+ rpm. That was unsettling. It now tracks straight and true, no matter how much power is applied.
The only downside is that it is a couple of mph slower 48 at 4000 before, now 45.5 at 4000. I'll take it.
Have not done WOT yet. Need a few more hours on the engine. I am sure as everything gets settled in and the rings seat, performance will only improve.
Cost for those interested:
Duoprop lower on ebay $1110.00
New seal kit, bearing and set up. $550.00
Stainless Steel C6 prop set. $980.00
total----------------------------$2640.00
Here are a couple of pics.

 

[Don S]

Re: Volvo 280 duoprop ?

Re: Volvo 280 duoprop ?

Holy hole shot Batman! Like instantaneous.

LOL, I knew that would be a big shock to you. Amazing how much difference there is between the DP and a single prop.

 

[Maclin]

Re: Volvo 280 duoprop ? UPDATED with install and sea trial.



Good deal!

Here are some numbers from my experiences with the "older" Swedish DuoProp drive:

I have a heavy 22 foot cuddy with 5.7 (275hp 570) and a 290DP. I run a B5 aluminum set and have seen 48mph at 4600-4700 rpm. Hole shot is very spunky and handling is great. Cruises effortlessly at 35mph and 3500 rpm. I tried a B7 set and it went past 50 at 4600 rpm, holeshot was a little different but still in the "pull anything out" range. The lake we frequent is small so I went back to the B5 set as we are almost always fully loaded and towing. We can cruise from one end and back inside of 15 minutes, no reason to have a top speed setup there.

I also think clocking the props is a good idea. Easy to do, does not hurt performance, reduces/eliminates chance of cavitation on this type of drive and can keep from inducing a vibration. Here is a link to a longer post I had started, may be meaningful .....: http://forums.iboats.com/showpost.php?p=1729834&postcount=1


Congratulations and hope you have many more days of happy boating.

 

[mtnrat]

Re: Volvo 280 duoprop ? UPDATED with install and sea trial.

Thanks for the link. I will clock the props and see if there is any difference.

 

[Speakrdude]

Re: Volvo 280 duoprop ? UPDATED with install and sea trial.

OK< I want one.....

 

[Don S]

Re: Volvo 280 duoprop ? UPDATED with install and sea trial.

OK< I want one.....

Do it. I know your boat, you won't believe what will happen.