Engine Swap?

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FF

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Joined
Oct 12, 2007
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As folks re-discover the fine early boats the question of an engine swop looms.

To me the hardest part o the swop would seem to be removing the old engine 3000lbs of 8V71 or 5000lbs of 12V71, especially in a boat with out the proper prior construction , a hatch setup so just a crane and hook does the job.

On TV I saw where many motorcycle thieves use a can of nitrogen to freeze metal to cold hardening and simply wacking it with a hammer.

I wonder if a properly prepaired worker could use this system , with a nitrogen truck , and breathing gear to do the same?

All the old parts are heavy so even items like the crank would be easier to stagger up a companionway after disassembly and breaking in pieces..

The new engine would be 1/3 to 1/5 the weight , and just removing the head and would reduce that a bit.

Then a simple skid setup might get it >down the hatch<?
 
Good thinking bad spelling Fred.

Yea most trawlers have old engines and many could use a swop.

And it would make better sense if one could be assured that when they sell the boat the next owner wold want half the power of the original boat. If not they would need to repower w roughly the same power if they wanted to retain the highest resale value. I question if fuel is that expensive yet. Big fuel gussling PU type trucks are selling well to very well and I submit that that could show that putting small engines in old trawlers could be a mistake even if the present owner would benefit from such a swop.

As to getting the old monsters out I suspect just cutting a hole in the roof and redoing it after may be the best bet. It probably depends mostly the specific boat as there is a lot of differences in the boats in this removal scenario. When we did Willy we used a forklift w a stout and long extension on a fork and snaked it through the aft salon door. For larger engines surgery on the aft cabin bulkhead may be preferable to cutting up the overhead.

Another thought re the swop is turning the big single engine boat into a twin. Or to keep the cost of the swop down ... a twin into a single. That would be more like installations than taking the old engine apart and removing it in pieces. But w a good running old Lehman or Perkins the market is excellent to sell the old thing so removing it ready to install in another boat has merit. I think most of the people rebuilding these old engines are making a mistake mostly because of the high cost of rebuilding.

So yes let the swops begin.
 

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