brianb00
O - 34
I have now replaced the Hurth 50 with the TMC 40 (Technodrive) in my Olson 34. This all bolts onto the flywheel of the M25XP. In all the task included a new transmission, new damper plate, new exhaust elbow/mixer (stock from Westerbeke), changing to 2" exhaust hose, modifying the old muffler to accommodate the 2" hose ( a day of fiberglass work), and many new bolts and washers. The engine was raised up about 3" using a dock bumper and bike pump. The bell housing and trans. just could be squeezed out and up after raising the engine and pulling it forward about an inch. Rusted bolts on the transmission flange were attacked with a torch and they came loose without to much struggle. The transmission requires raising the engine 0.21 inches which I did with precision spacer washers at each engine mount. The tran. output flange fit perfectly on the prop shaft flange and the PSS seal was not disturbed - it still functions. The alignment was inside .003", it actually depends on the backstay adjuster tension. The exhaust elbow is a touch lower than the original Universal version and interferes with the heat exchanger. So that has been slid a couple of inches to starboard. It was tested in the slip a few hours ago with a 30 sec run. Amazing forward power with a transmission whose clutch isn't slipping. I have about an hours worth of work left to clean up and optimize the exhaust/heat exchanger positioning, then a full power in the slip test to hopefully seat things, and a re tightening of critical bolts. Total hours getting this done was about 20, costs: Trans $1250, exhaust riser $250. , Damper $430, 2" exhaust hose $30, misc new bolts/washers/oil/grease about $80. Thanks for the advice/photos I found here and other sites. Glad to have this complete.