Volvo 290 SP to DP conversion Questions

[69seabird23]

Kind of complicated, but I'll try to be concise. (I searched the forums, but couldnt really find all the answers)<br /><br />I own a 23' seabird with a 1989 200hp Volvo Turbo Deisel AQAD41A. It is driven by a 290 SP outdrive. The U-Joint is starting to go and I need to haul the boat and have it serviced. I would love to convert it to a duoprop. I have found locally a complete 290 DP outdrive on a 1977 SeaRay with a Chevy small block. (I have posted links to pics of this). Question: will this work? Will the difference in age of the two matter? Will there be gear ratio problems? Also, I have a left handed rotation. The replacement is right handed I'm guessing. Is this a problem? <br /><br /> http://i41.photobucket.com/albums/e295/rseifert33/Replacement2902.jpg <br /><br /> http://i41.photobucket.com/albums/e295/rseifert33/Replacement2901.jpg <br /><br /><br />Thanks for any help guys!<br />Rick

 

[rodbolt]

Re: Volvo 290 SP to DP conversion Questions

nice thing about the DP, its neither right nor left.<br />all volvo cone clutch units have to have left hand rotation inputs.<br /> the biggest thing with a diesel drive is to select the lower gear in the upper unit as fwd.<br />can be done with linkage changing or control box throw changes.<br />the DP unit will bolt onto the 290.<br />however the gear ratio of the old and the DP will need to be known. volvo uppers are mostly all the same, the ratio changes in the lower.<br />DonS will know a lot more about that swap than me.<br /> I just fix them. he is a master at it.

 

[69seabird23]

Re: Volvo 290 SP to DP conversion Questions

Thanks for the reply Rodbolt. Would it be easier to just put the entire replacement drive on my boat instead of bolting on the lower DP unit? <br /><br />I was told that because I have a deisel motor and this drive is from a gas motor, it will present gear ratio problems. Do you know anything about that?<br /><br />Who is DonS and how can I chat with him?

 

[Don S]

Re: Volvo 290 SP to DP conversion Questions

You would only need to replace the lower unit to convert to a DP, you don't need the complete drive. You will also need a 1.78: 1 gear ratio, and the Chevy should have a 1.98:1. Diesels also require a different type of props than what is used for gas engines.<br />Like robolt mentioned, there isn't a big deal in changing direction if needed.<br /><br />PS: Rodbolt..... Master? Not by a long shot.

 

[69seabird23]

Re: Volvo 290 SP to DP conversion Questions

You say that the deisel and chevy gear ratios are different. What do I have to do then to bolt the DP lower to my outdrive? If those ratios arent the same it won't work right?

 

[lilmandavis]

Re: Volvo 290 SP to DP conversion Questions

need new gear set. with the correct ratio. and the diesel props. dons no master!! hes just a smart azz!!! you know your shizit don, dont be modest.

 

[69seabird23]

Re: Volvo 290 SP to DP conversion Questions

Do you guys know about how much and where I could get a gear set? I asume that would take a professional to change them huh?<br /><br />I apologize for the stupid questions, but I'm new to stern drives, much less duo prop conversions.

 

[rodbolt]

Re: Volvo 290 SP to DP conversion Questions

Ill argue outboards all day long with DonS.<br /> I will argue a bit with sterndrives but usually will defer.<br /> Dons for the past 3 years that I have participated here has shown nothing but exemplery skill and knowledge.<br /> even if we both get red dots on our foreheads sometimes.<br />some folks call them WALL marks.

 

[Don S]

Re: Volvo 290 SP to DP conversion Questions

like lmd says, a new gear set is what is needed to get the gear ratio right. But don't think that is a minor thing. The gear set alone is 1300 bucks. Then you need bearings, seal kit, and the labor to put it together. A set of props is around $700 list as I recall.

 

[Don S]

Re: Volvo 290 SP to DP conversion Questions

Ya ain't gonna argue outboards with me, them things run on magic. Always have..... Now that they stuck EFI on them they have Magic and Voodoo.<br />Not something I want to deal with.<br /><br />

 

[69seabird23]

Re: Volvo 290 SP to DP conversion Questions

Damn, looks like this isnt really gonna work out. It's a 1969 boat, that's in good shape, but I dont know about sinking thosands into the drive. I already have to have the U joint fixed. That'll be a pretty penny right there. Maybe I'll just fix that for this season and think about the conversion. Seems like buying a rebuilt with the proper ratio would be the best idea. Thanks guys!<br /><br />I just really hate the damn prop steer!!!

 

[69seabird23]

Re: Volvo 290 SP to DP conversion Questions

One more quick question.....What if I just put the entire replacement outdrive on there? Would it still have a problem matching to the motor? Is the gear ratio that much different that it would cause a problem? My motor cruises at 3400 to 3800 rpms.

 

[Don S]

Re: Volvo 290 SP to DP conversion Questions

You MUST change the gear ratio and prop type going from gas to diesel. It doesn't matter if you are changing the complete drive or just the lower.<br /><br />In case that is to hard to comprehend, try this.<br />The drive in your pictures WON"T WORK!

 

[69seabird23]

Re: Volvo 290 SP to DP conversion Questions

Hey Don S.....what does that stand for? Don't Know ****? Thanks for the wrong advice. Drive works fine!

 

[Don S]

Re: Volvo 290 SP to DP conversion Questions

Guess I used the wrong terminology, instead of saying it "won't work", I should have said it "won't work properly or effeciently". <br />Yea, it'll bolt up and make your boat go forward and backward, but you won't have the effeciency, speed, or power you should have.<br />I didn't give you wrong advise, you wasn't going to follow anyones advise anyway, or you wouldn't have bought it.

 

[bruceb58]

Re: Volvo 290 SP to DP conversion Questions

Another satisfied customer!!!!

 

[rodbolt]

Re: Volvo 290 SP to DP conversion Questions

Dons getting them red dots again, I got mine yesterday at work. dont need anymore