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lakenottely
04-19-2010, 05:25 PM
Water has been entering the bilge area of my X7 for the past few years.

Mystery solved:

After removing the XPC Dripless Shaft Seal System, it is obvious where the water is coming from.
The XPC Dripless Shaft Seal System has failed.
Checking the engine alignment appears to show why.
It appears to be a problem with alignment of the Strut and Shaft Log.

I have to believe that my boat left the Factory with the misalignment of the Shaft Log and Strut which was the primary cause of the premature failure of the shaft seal.

The propeller shaft is angled toward the bottom of the Shaft Log.
Lifting the propeller shaft upward with the engine coupler disconnected with a good bit of force will get about 1/8 off the bottom of the Shaft Log.
To center the shaft in the Shaft Log, it requires loading thethe propeller shaft to the point of bending it..

I spoke with Mastercraft Technical Support. As usual, they refer you to visit a dealer. Maybe if they would belly up to the bar and try to help the customer, they could improve their customer satisfaction.

I need to implement a fix that will prevent the premature failure of the shaft seal as it didnít last about a year the first time.

Has anyone made an anageled brass shim to correct the geomentry of the strut?

Any recommendations will be appreciated

TMCNo1
04-19-2010, 07:13 PM
It has nothing to do with shimming the strut or anything of the like, it's about doing an engine alignment as it should be done by a competent dealer or per this DIY pdf, http://www.mastercraft.com/teamtalk/showpost.php?p=639908&postcount=16, (http://www.mastercraft.com/teamtalk/showpost.php?p=639908&postcount=16)
especially since the boat is at least 5 years old and it is something that needs to be checked periodically anyway by you or your dealer.

FrankSchwab
04-19-2010, 07:59 PM
You aren't the first one to have this happen.

Unfortunately, if the shaft is forcibly touching the bottom of the shaft log with the coupler disconnected as you describe, an engine alignment won't help - you'll be able to meet the 0.003" adjustment, but the propshaft is going to be bent to do it. Eventually, this may cause the propshaft to fracture. Make sure you can tell the difference between "propshaft being pushed into the side of the shaft log" and "gravity pulling the propshaft down into the shaft log" - the second isn't a problem.

It seems to me (as a random poster on teh intertubes) that you have two possible problems:
1. The strut is bent. The strut is the center of the world when it comes to the propshaft; it's non-adjustable and rigidly secured to the hull. Whatever angle it sends the propshaft up through the hull is the angle that everything has to be adjusted to. If it's bent, it won't send the propshaft through the shaft log correctly, and the propshaft will bend (and thus ride on the side of the shaft log) to get through the hull.
2. The strut is installed incorrectly. If contamination (say a bit of fiberglass) got under one end or the other of the strut mounting plate, it could move it far enough to upset the alignment of the propshaft with the shaft log.

Remember, the propshaft doesn't have to go through the center of the shaft log, it just has to go through without touching the sides (much). A slight misalignment can be brought back with a bend induced by the engine alignment; but I don't know if anyone has a spec for how much force is acceptable to do this.

I don't know how to determine which of these two options (or some unspecified third or fourth option) is the real issue; good luck with that.

Some previous threads:
http://mastercraft.com/teamtalk/showthread.php?t=25215
http://mastercraft.com/teamtalk/showthread.php?t=31002
http://mastercraft.com/teamtalk/showthread.php?t=15000

/frank

lakenottely
04-19-2010, 08:26 PM
Thanks for the reply.

lakenottely
04-19-2010, 09:05 PM
It has nothing to do with shimming the strut or anything of the like, it's about doing an engine alignment as it should be done by a competent dealer or per this DIY pdf, http://www.mastercraft.com/teamtalk/showpost.php?p=639908&postcount=16, (http://www.mastercraft.com/teamtalk/showpost.php?p=639908&postcount=16)
especially since the boat is at least 5 years old and it is something that needs to be checked periodically anyway by you or your dealer.
The shaft being way off center can not be corrected by engine alignment.

JerryW
04-20-2010, 08:07 AM
I had the same problem with an '02 X-9 with an LQ-9. Pulled the transmission to replace the damper plate, and learned the prop shaft to engine alignment was way off. The engine alignment was way over to the drivers side, and bottomed out in the front - could not adjust it in the direction it needed to go to align it to the prop shaft. I think it must have left the factory that way, because I never did anything to change the alignment previously. Also had a slightly bent strut. I centered the engine from side to side, raised the front to give me some clearance in case I need to re-align or fine tune it in the future. I got a new strut, shimmed the back of it to get the proper angle to meet up with the re-positioned engine, and realigned the opening in the hull to adjust the position of the shaft log. In the end, got it to align within the .003 tolerence needed. There are plenty of posts on this forum that I followed on doing all of this, not all that hard, just time consuming.

lakenottely
04-20-2010, 08:46 PM
I had the same problem with an '02 X-9 with an LQ-9. Pulled the transmission to replace the damper plate, and learned the prop shaft to engine alignment was way off. The engine alignment was way over to the drivers side, and bottomed out in the front - could not adjust it in the direction it needed to go to align it to the prop shaft. I think it must have left the factory that way, because I never did anything to change the alignment previously. Also had a slightly bent strut. I centered the engine from side to side, raised the front to give me some clearance in case I need to re-align or fine tune it in the future. I got a new strut, shimmed the back of it to get the proper angle to meet up with the re-positioned engine, and realigned the opening in the hull to adjust the position of the shaft log. In the end, got it to align within the .003 tolerence needed. There are plenty of posts on this forum that I followed on doing all of this, not all that hard, just time consuming.
From reading on the net, it appears there have been a lot of Mastercraft leave the factory with strut & shaft log issues.
If Mastercraft really stood behind their product and cared about their customers, they would take responsibilty and fix the problem free of charge. Instead, the customer has to spend their time and money to resolve the issue.

The longer I own my Mastercraft, the more I'm pissed about wasting my money on product from a company that screws their customers with a bad product.
Quality control and customer service is what defines a a great company.