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Discussion Starter #1 (Edited)
The shaft of my 3gmd is off on the side towards port.

Should I be able to loosen engine mount and move the shaft starboard a few mm

Can I do this on the hard ?

 

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Master Mariner
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You should probably check your shaft and strut as well. Pull the cutlas bearing and check the wear. This appears to be way too much out for just the engine, but I'm not there so I can't say this for sure.
Is it possible you hit anything with the strut or prop recently?
 
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Learning the HARD way...
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The shaft of my 3gmd is off on the side towards port.
That's putting it mildly...

Should I be able to loosen engine mount and move the shaft starboard a few mm
You should, but as the previous poster states, you should check your strut (and cutlass bearing) and your shaft seal (either dripless or stuffing box) too. You will be moving the entire drive line to starboard, and will need to realign the engine.

Can I do this on the hard ?
Yes!
 

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Learning the HARD way...
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...But on the positive side of the ledger, it looks like you don't have to worry about barnacles.
 

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On the hard you can align the engine but it will not necessarily be perfect. If the strut and shaft are good, then do the alignment on land and fine tune it after a few days sitting in the water.
The flanges for the trany/shaft connection are where you measure the alignment, not outside the boat where you see the problem. Undo the bolts and you will see if the two surfaces of the flanges line up. You will be working in hundredths of an inch here, not visually. You will need to loosen all 4 motor mounts and have a set of feeler gauges to use. The flanges must line up as nearly perfect as you can get them, both as parallel flat surfaces and the outer circumferences.
If the flanges line up or you cannot get them to line up at all, and you still have the offset where the shaft exits the hull, you have a bent or improperly installed strut or bent shaft. Spinning the shaft by hand against a fixed point, (a 2 X 4 clamped to the rudder, a stand, etc.) will tell you of a major bend.
Checking the alignment of the strut may be something only a yard can do, unless you have the specific tools.
 

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Don't call me a "senior"!
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Given that there appears to be that much misalignment I would be willing to bet that: your strut is loose, you cutlass bearing is shot, your strut is or way out of alignment, or some combination of these. Best thing to do is to uncouple the shaft from the transmission and see where it wants to line up with just the strut/cutlass to guide it. Make sure that the shaft isn't loose in the cutlass bearing and that the strut is firmly attached to the boat. If those are OK, you can start playing with the alignment.
 

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Dirt Free
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Don't pull the trigger too fast. I see this all the time and it does not mean anything is out of line. Many boats leave the factory this way, The "glass" all around the shaft aperture is most often about a 1/2" of gelcoat manually (crudely) applied after the hull came out of the mold. Before taking action check the flange coupler with a feeler gauge, inspect cutless bearing and strut securement.... if they are ok then you have nothing to worry about.
 

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Bombay Explorer 44
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I would take a real hard look at your engine mountings and the engine bearers themselves.

If nothing obvious then watch what happens when someone puts it in gear forward then reverse. Sometimes engines are just sitting loose on broken mounts or bearers.
 

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A Cat 30 in our club had been running with a similar issue for years. The fiberglass was worn almost completely through before it was caught. It required removal of the shaft so the fiberglass work could be done.
 

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Discussion Starter #10
She always vibrated when turning under power.

The propeller caught the dinghy line probable made it worst.

A couple people looked and said cutlass looked good. Strut looks and feels solid.


Sent from my iPad using Tapatalk
 

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Corsair 24
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your shaft is probably shot after the dinghy incident especially of it was this close to the hull

take it off...true it...finish off hole...realin engine and bobs your uncle
 
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