MD7A replacement need info

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Jack Cothren

MD7A replacement need info

Post by Jack Cothren »

it looks like my MD7A has bit the dust, without going into the particulars i am looking into a replacement motor for a CD 28...i've been in contact with ken cave and his 28, re his repowering with a volvo 2020...tomorrow i'm checking out dennis truett's rare CD26 diesel with the original 86 10-11hp westerbeke diesel (the current westerbekes 2 cylinders are 18 and 12? hp and have the same "envelope") i am looking into the volvo 2020,westerbeke 20 B2, Universal M3-20B, and of course the Yanmar 2GM20F...if anyone can help with the above in regards to extent of modifications (ie $/ hrs) of the engine compartment with the above motors and the Technical Line drawings of the MD7A i would be extremely greatful...also if you live within a few hours of the Hudson river and replaced your engine with any engine in a CD 28 i would love to hear from you and possibly see it

....jack cothren
KINGFISHER
CD 28 # 238



jcoth49@aol.com
Richard Hill

Re: MD7A replacement need info

Post by Richard Hill »

I replaced an Atomic 4 in my Bristol 32 (11,000 lb displacement) with the Volvo MD2020. It's really a nice engine (it's actually a Perkins M20 - even says Perkins on the block). It's light weight and runs very smoothly and quietly. I also looked at the Yanmar 3GM, which has more peak HP, but went with the Volvo. It has a torque curve that is almost flat across the rpm range. Yanmar doesn't achieve peak hp or torque low in the rpm range. Don't know what you would encounter in changing the engine bed, but it's not insurmountable. Another reason I liked the Volvo is that you can get a gearbox with the shaft angled downwards a few degrees. This helps the engine sit almost level with the shaft lined up, rather than the whole engine/gearbox sitting in the boat at an upward angle.



captrahill@comcast.net
Paul Hierstein

Re: MD7A replacement need info

Post by Paul Hierstein »

Richard Hill wrote: I replaced an Atomic 4 in my Bristol 32 (11,000 lb displacement) with the Volvo MD2020. It's really a nice engine (it's actually a Perkins M20 - even says Perkins on the block). It's light weight and runs very smoothly and quietly. I also looked at the Yanmar 3GM, which has more peak HP, but went with the Volvo. It has a torque curve that is almost flat across the rpm range. Yanmar doesn't achieve peak hp or torque low in the rpm range. Don't know what you would encounter in changing the engine bed, but it's not insurmountable. Another reason I liked the Volvo is that you can get a gearbox with the shaft angled downwards a few degrees. This helps the engine sit almost level with the shaft lined up, rather than the whole engine/gearbox sitting in the boat at an upward angle.


There was a bit of discussion on this issue some time back. You might try contacting Beta Marine and look at their Kubota model 722 (I think). Someone on the board put one in their CD and had great success with it. In addition, the price was very attractive!
Good luck!

Sinsailorly,
Paul
Abre Alas
CD30C
Galveston, Texas



paulhstn@aol.com
Ken Cave

Re: MD7A replacement need info

Post by Ken Cave »

Just looked at the Beta Marine web site, and I purchased my Volvo 2020 on the west coast with all the upgrades for less than $5900!

Looks like they use the same block-and wonder if Perkins did the work in making this engine useful for us sailers-and then painted it red instead of green!

Ken Cave
New Engine-poorer but happy!!



bcave@whidbey.net
Richard Hill

Re: MD7A replacement need info

Post by Richard Hill »

Ken Cave wrote: Just looked at the Beta Marine web site, and I purchased my Volvo 2020 on the west coast with all the upgrades for less than $5900!

Looks like they use the same block-and wonder if Perkins did the work in making this engine useful for us sailers-and then painted it red instead of green!

Ken Cave
New Engine-poorer but happy!!

The dealer said Perkins built the block (although I've seen other references to it being a marinized Japanese block). The difference between the Perkins M20 and Volvo MD2020, color aside, is in the heat exchanger system and the electrics. Block is the same. It's kind of funny looking at a green engine that says Perkins, though!



captrahill@comcast.net
Ben Thomas

Re: MD7A replacement need info

Post by Ben Thomas »

Jack, I am replacing my md7a with the beta-marine 722 (20hp) with the hurth v-drive. (2.13) The engine is a kubota block and is marinized by beta out of England.
The engine and vdrive is much shorter and 170lbs lighter than the volvo. I'am repowering this coming weekend, pulling the volvo,wiring harness etc. and will keep the board posted. I will post Stanleys Number out of Carolina who is the main distributor here in US. This engine matchs up quite well with existing mounting beds prop shaft etc. Ben



bt@benthomaslandscapers.com
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