Replacing gears in Volvo outdrive. Would you??

[hd883chopper]

'89 Volvo duoprop geared for a V6 now has a GM V8 350 cui. 21' Rinker Cuddy

Hello everyone,

I was wondering if I could get some advice. Should pursue this or not? I bought a nice rig last year, it has a Volvo outdrive with a GM 350 motor pushing it. It runs good, the only problem is I can only run half throttle. The fella who owned it before me replaced the V6 with a V8 but never replaced anything behind the motor.

Consequently, I have a whole lot of horsepower that I can't use because all I do is tach up. At first I thought the problem could be fixed with a prop change. I've learned its not that easy. I've got mechanics telling me that a gear change would be necessary.

- Would you experienced folks consider replacing the gear pack?

- Is this risky? Meaning could I be opening up more issues than I could possibly fix?

- Mechanic mentioned that I may have an upper gear set as well as a lower (he hasn't seen it yet). Would an '89 Volvo outdrive have upper and lower?

- Finally, does $1500 sound reasonable for the lower gears? This includes a proper pitched alum prop and labor.

Thanks for any comments or advice!
hd.

 

[Don S]

Re: Replacing gears in Volvo outdrive. Would you??

If you don't have the special tools and the know how to rebuild a DP lower, the chances of success are somewhere near 0.
As far as cost, the lower gear set for a 1.95 gear set alone, is $1800 list. that does not include labor, bearings, seal kits, and sure doesn't include a set of props or even repitching a set.

- Mechanic mentioned that I may have an upper gear set as well as a lower (he hasn't seen it yet)

At this point, I bet your mechanic doesn't realize a DP is Duo Prop, and is thinking a single prop drive.

 

[hd883chopper]

Re: Replacing gears in Volvo outdrive. Would you??

Thanks for the reply Don and the info. I'm hoping to have a more detailed discussion with the shop early next week. Might even bring the rig over there to have the take a peak. Wow, $1800 just for the lower gears eh? I know I haven't given a ton of info but do you think there is "upper" gears that would have to be replaced as well?

He mentioned on the phone that some have gears upper and lower but most are just lower. Any idea?
Thx,
hd

 

[Don S]

Re: Replacing gears in Volvo outdrive. Would you??

Might even bring the rig over there to have the take a peak.

I don't believe he even gave you a quote without seeing it, that's just crazy, especially if you don't give him the proper information for him to base his quote on. Quoting boat repairs over the phone without seeing what your getting into is stupid, and usually done by those that shouldn't be working on it to begin with.

He mentioned on the phone that some have gears upper and lower but most are just lower. Any idea?

There is another example of incomplete information. ALL outdrives have upper and lower gears.

 

[hd883chopper]

Re: Replacing gears in Volvo outdrive. Would you??

How about you give us the actual model of the drive and the current gear ratio?

Believe me Bubba, I wish I could. Bought the boat used at the tail end of last summer and I'm trying to get all this hammered out going forward. The most I know is that when it was bought new, it had a 4.3 6cyl engine (which is gone now and has since been replaced w/ a V8 by previous owner). The original Volvo outdrive is on it but the only distinguishing marks is some badging that says DP CD Trim. I can plainly see it's a duoprop but that's about all I can determine. I didn't see any stamps or indicators telling me exactly what it is. Unsure of what the ratio is either, I'll have to get someone who is knowledgable about the set up to look.

I talked to another mechanic who specializes in Volvo and asked me to bring it in. He sounded pretty confidant that a set of gears (and a replacement prop) designed for V8 power would or should take care of my problem.

To reiterate my problem: I have a V8 motor and still have an outdrive and prop for a V6. So when I'm out on the lake running, I can only give it about half throttle. Any more and the motor just starts to rev up too high. At half throttle, I'm running about 35mph. In my opinion, a 23' Rinker Cuddy should be running faster than that with a 350ci V8.

 

[Tail_Gunner]

Re: Replacing gears in Volvo outdrive. Would you??

There should be a stamped piece of metal on the lower leg of the out drive. On it you should see a number stamped 1.89 1.66 find that and try to post it. A 1.66 should not need a change...it may cost some overall small performance in hole shot or top end. Duo props are expensive and gearing is worse.....maybe a 3500 job all said and done....Try to post the gearing if it is a 1.66 its not that bad