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Topic Title: ENGINE ALIGNMENT?
Topic Summary: MARINA MECHANIC THINKS I NEED AN ENGINE ALIGNMENT.
Created On: 10/30/2007 10:08:26 AM
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 10/30/2007 10:08:26 AM
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MJGT
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Joined: 03/24/2006

boat is out for bottom job. I had thought I had a bent prop shaft, after trying to change packing gland on port side. After the boat was pulled the mechanic manager looked at it and doesn't think the shaft is bent but that the engine is out of alignment. based on:
-prop turns by hand easily
-very little noticable vibration while underway.
-prop shaft exits hull left of center of shaft hole in bottom of the boat.
He says that out of alignment will cause the cutless bearing to fail.
I thought the shaft was bent because:
-I could not remove the pack nut on the shaft log
-I could see a small amount of osulation in the shaft while turning in gear.

My question is... In a 1995 boat with 700 hours on it, how would the engine become out of alignment? Never had any major work, runs great, gentle owners.

About 3 months after I got this boat I ran aground at idle speed into sand.
I bent the props trying to back off. (rookie mistake).
I am wondering if I bent the strut accounting for the shifted postion of the shaft as it exits the hull. Any thoughts, Ideas, or comments would be greatly appriecated.
thanks Mike

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Mike <BR>lake texoma, 1995 44 gibson standard
 10/30/2007 10:56:53 AM
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stmbtwle
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I agree you may have a bent strut, it can cause the symptoms you describe. The oscillation in the shaft though is more indicative of a bent shaft. Once you correct all that you'll need to realign the engine anyway.

Running aground will do all of it, as well as the props.

I'd compare the strut with the one on the other side and/or check it with a square. If it's seriously bent you should be able to see any difference. If it's only minor, realigning the engine may be all you need to do. Uncouple the shaft from the engine and slide it back half an inch, any misalignment will be apparent. Then spin the shaft by hand. if it still wobbles it's bent.

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Willie
She's a tired old barge but she's paid for! http://s71.photobucket.com/alb...p;current=ef324993.pbw
 10/31/2007 08:37:35 AM
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MJGT
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thanks for the reply stmbtwle. sounds like the Marina is right on. thanks for the reassurance.
What does your user name stand for? Steam boat Willy?

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Mike <BR>lake texoma, 1995 44 gibson standard
 10/31/2007 09:15:51 AM
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Sideways
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Joined: 10/26/2006

It does sound like you have a bent strut. If you can see the shaft move out of alignment when it is running then you also have a bent shaft.
Sometimes the shaft will bend in the taper ( where prop is) and that will not show up on the engine side of the strut. We repair or replace when it is bent more than four thousandths.
Most shops will replace the shaft if it is bent in the taper but a sharp machinest can straighten it.
There are several things you can do to find out but the boat must be out of the water. Where the shaft is located in the cutlass bearing ( outside ) is a dead givaway.
Good luck

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sideways
 10/31/2007 06:05:57 PM
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MILLERTYME
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Joined: 02/20/2006

remember to wait to align your engine until after you have been back in the water for a few days to allow the boat to "settle". if you try to align while on the trailer or while blocked you will probably have to do it again since most fiberglass boats will flex when pulled out of the water.


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UC FANS
1999, 52' Monticello - Miller Tyme
Port of Aurora IN
 11/01/2007 06:25:37 AM
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stmbtwle
Admiral

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Joined: 04/22/2003

bingo

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Willie
She's a tired old barge but she's paid for! http://s71.photobucket.com/alb...p;current=ef324993.pbw
 11/02/2007 11:58:28 AM
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houseboat8972
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Another thing to look at would be the shaft coupling itself. If one of the set screws is worn more than the other, it may have "wallowed" out somewhat and make the shaft appear to be bent when it turns. Be sure and replace your set screws while you are at it.
 12/17/2007 03:45:04 PM
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MJGT
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Joined: 03/24/2006

BUMP

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Mike <BR>lake texoma, 1995 44 gibson standard
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