The engine in Jet Stream was an Atomic Four. After much research about engines and such, I have decided to replace it with a Westerbeke diesel. I also looked at the Yanmar and was impressed by its service record and owner reviews. However, I found that with the Yanmar, I would lose about 8" of headspace and also have to redo the engine mount. The engine mount in Jet Stream is quite substantial and in very good condition. The Westerbeke option with their Atomic Four replacement mount setup, is a bolt-in (ha ha ha) replacement with little or no change in space requirements. I elected to do this job myself and again used my trusty 2 x 12 x 16' "Lifters". I used them to make a frame that I attached with a bridle fore and aft. I ran the forward bridle through a block and back to the sheet winches. Then by canting the frame, I could move the engine back. The engine unbolted with no difficulty. I was surprised to see that after all these years, the fasteners were not a problem. I also rotated the crank to see if the engine were siezed, and it turned easily. With the new electronic ignitions and so forth available at Moyer Marine (www.moyermarine.com), I think this engine would be perfectly rebuildable. In fact, I've heard that Atomic Fours from the early 60's had larger water passages and less cooling system problems. The exhaust on Jet Stream was a copper jacketed style that is not popular now because of the difficulty of checking for internal corrosion. I will replace it with the water lift style. With the "Lifters", my little helper and I were able to have the engine out and on a trailer within a couple of hours.
Engine Before Removal
As an update to this page, the old Atomic 4 engine will be hopefully getting a new home with a new life. It was delivered on November 26, 2002 to Triangle Marine Engineering, Ltd. in Quonset, RI with expectations of being rebuilt and added to Pearson Triton hull #80 "Bellatrix", owned by Kate Ambach. I wish her much success with her rebuild and hope that the engine provides good support on her future cruises.