Chrysler Crown M47 w/ hydraulic reverse gears - shift adjustment ?

Ned L

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Sep 17, 2008
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A long shot, but I figure i'll ask. .... Anyone have experience adjusting the F-N-R shifting on a Chrysler Crown M47 w/ hydraulic shifting. I have a pair that shift sluggishly. I have the manual and figure I'll look into it this winter.
.... These are 1957, 265 cid flat head sixes that weigh about 925 lbs each.
 

K-2

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Apr 3, 2011
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Who built the gear? Paragon? Are you sure there is an adjustment, other than linkage adjustment? Maybe someone used the wrong oil.
How long have you owned them? Did they shift better before? The only Crown / Royal gears I have seen were the older mechanical ones.
 

Ned L

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K-2. - I have had the boat only since early July, haven't had it on the water yet ( that's another whole topic - pretty in-depth restoration). You are correct about them being mechanical. Chrysler had a "hydraulic" option back then that is a bit funky. As with typical mechanical reverse gears these are common with the engine crank-case oil. There is a hydraulic shift mechanism on top of the mechanical gear. Essentially there is a hydraulic cylinder (run off the engine lube oil pressure) that has a fork which shifts the mechanical gear. With this you have a typical 'teleflex' type cable that runs to the helm, when you shift F-N-R you are changing the valving to the cylinder, which then shifts the mechanical gear. I have the full Crown manual and it does discuss the adjustment, but it says there is some trial and error between adjusting the hydraulic portion and the mechanical gear, sort of a balance point between the two.
Oh, and I don't know who actually built the gear. It could actually be Chrysler, (they built so many Aces, Crowns, & Royals over the decades.
 

K-2

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Apr 3, 2011
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OK I can picture that shifting system. So you have slow shifting now,,and it could be the marine gear itself or the shifting mechanism, or a combo of both (?)
 

Ned L

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Yes, that's about where I am. The boat hasn't been in the water in 15 years so I'm thinking it can't hurt to pull the hydraulic units and give them a good going over.
 
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