Volvo Kad41 & 290 outdrive

[brian_g]

Volvo Kad41 & 290 outdrive

Do any of you guys have an opinion on this engine/outdrive combo? lifespan, problems, things to look out for?

Thanks!

[DOGHOUSE26]

I don't think Volvo made a KAD41; they did make a KAD42, KAD43, and KAD44. The K stands for Kompressor, or supercharger. they are all based on the base AD41 200HP 6 cylinder block . First generation was the KAD42; I think about 230 HP at the shaft; they had a few piston problems in early units not being able to take the heat or additonal HP. The improved KAD43s were much better I think 260 HP but the supercharger was still pretty noisy when it engaged; I believe there was a switch to disengage it once the turbo kicked in.The KAD44s were much improved with a better supercharger and I think electronic fuel monitoring; maybe 260-300 HP I'm not sure.

The 290 outdrive is just 1st generation Duoprop model; minor changes over time like tilt rams, prop cones, exhaust outlets, etc. until the DPX drive was introduced maybe 5 years ago. Now the new units have a different drive all together .

If it was me I would stay away from the 42s, try to get a later model 43 or 44 and you would be very happy. Fishwiz Glenn has a 42 in his 84 Billfisher and his flys along pretty good; he's done alot of service work to his motor but I don't think he has had a catistrophic failure yet. I have a friend with a 25 Skippy Pilothouse repowered with a newer 43 and it hauls ass and gets great fuel milage. I talked with Don Blackman years ago about the supercharger and he said it was just something else to repair, and he did not like the supercharger whine in the 42s and early 43s; he thought the noise scared away trolling strikes. But the later models were quieter and more reliable so he wasn't as opposed to installing them as he once was.

My opinion is based on just little bits and pieces of info I've gathered over the years, I've never seen a detailed written specification breakdown or comparison article for all of those units.

I think No Slack Mike posted this link for Volvo Motor Specs:

http://www.volvo.com/volvopenta/glob...marineengines/

[Wizard]

Just wanted to mention, on the subject of the KAD42. I think only the first KAD42s had the piston problem, and those had their problem early in life, or not at all. As for the Kompressor, it is loud, but it's only on from about 1500 to ~2800 RPM, or something like that. Which means I'm on plane in a few seconds, since the boost making up for turbo lag is so significant, then it shuts off at cruise speed. For trolling speed, I do have the shutoff switch.

[DOGHOUSE26]

See , I told you I'm no expert and Glenn probably would be your best source for KAD questions. He has gone through his rig inside and out to get it in the fine shape it is in today. I do know there were alot of KAD motors put in Davis offshore boats similar in size and weight to the Blackman 26s; they would be a good source also as Davis was a little more speed performance oriented than Don was and believe me that extra 30-60 HP makes a world of difference as Glenn will tell you. Good Luck with your search

[Knot Now]

Just a note on the 290 outdrive. Replacement or overhaul ($4,000 to $6,000) comes at 1700-2000 hours. Volvo recommends overhaul at 1000 hours.
Phil

[brian_g]

Thanks for the information guys!