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ChrisG
03-21-2005, 01:09 PM
I just got off the phone with my dealer and he informs that my shaft is out of tollerence by .0020 (twenty thousanths). He recommends replacing it because it may lead to bigger problems down the line. Its going to cost me close to $600 for parts and labor. This is on top of the $600 for the 100 hr service. Its turning out to be one expensive service trip... :cry:

NSXBill
03-21-2005, 01:23 PM
First off, 0.0020 is 20 TEN thousandths. You probably meant 0.020. Your fingernail is about that thick. Did it have a vibration? What was the dimension they are referring to? A total indicated runout (TIR)? What tolerance do they say is allowed?

$600 to replace a shaft? Jim?

These are the questions I'd be asking...

Ric
03-21-2005, 01:41 PM
First off, 0.0020 is 20 TEN thousandths. You probably meant 0.020. Your fingernail is about that thick. Did it have a vibration? What was the dimension they are referring to? A total indicated runout (TIR)? What tolerance do they say is allowed?

$600 to replace a shaft? Jim?

These are the questions I'd be asking...

Yes, I'd be questioning this too. .002" is two thousanths of an inch
if it is .002 out of tolerance, what is tolerance? .005" TIR? more? / Less?
Ask what Bill asked... What is the TIR and how did you check it?

Send the shaft to me and I will check it for runout and tell you what it is and most likely can make you a new one for less than OEM.
Now, the problem will be that if I make it, you have to install it or pay the dealer to install it and you obviously already owe him for taking it off or for at least diagnosing the problem?

ChrisG
03-21-2005, 01:58 PM
Ric and NSX, thank you for your reply. The guy told me it was twenty thousanths (sorry about the decimal error) out of tollerance and that Mastercraft's maximum tollerance is three thousanths. I just don't want to get hosed here. The dealer has always been great and I would hope they wouldn't be shafting me (no pun intended). The thing is, I have never noticed any type of vibration. Thats why I quesiton it. And, if it is out of tollerence, I don't want it to lead to bigger problems down the line.

BriEOD
03-21-2005, 03:00 PM
Get it straightened at a machine shop >$100.

Nova Scotia Skier
03-21-2005, 03:10 PM
I have a question about shaft tolerances. :confused: I know shafts shouldn't be bent, but maybe someone can tell me why there is a .005" runout tolerance on a shaft that is going to flex far more than that when accelerating. Same goes for coupling alignment. I know it has to be good, but good at what motor position? still or at speed. The motor torques, and it's mounted in rubber. Isn't it gonna move? Also, the shaft log is made for movement.

Like I said, just a question. Maybe a dumb one though. :wavey:

east tx skier
03-21-2005, 03:17 PM
Hey Brian, what's the name of that shop in SC that you used. They couldn't straighten my father-in-law's last summer, but its bend couldn't be measured in thousandths. ;)

NSXBill
03-21-2005, 03:18 PM
Mastercraft's maximum tollerance is three thousanths.

.003 TIR for a boat propeller shaft is max? I'm curious if we are really talking TIR here and how they measured it. I guarantee they didn't take it off the boat. I wouldn't even think MC has a figure for this. They do specify (and hopefully check for $600 100 hr service) the side-to-side gap difference between the shaft flange and the transmission flange (when disconnected), but this would show an engine alignment prob, not bent shaft....

ICBW

ChrisG
03-21-2005, 03:56 PM
I want to thank everyone for their information. I went ahead and gave them the okay to replace the shaft. I'll go ahead and eat it this time (due to the fact that the boat is already in for the 100hr service), but next time I know I'll be able to take it and have it straightened for a lot less. BTW, there was no damage to the prop. Makes me kinda wonder how the shaft originally bent. :confused:

AirJunky
03-21-2005, 04:00 PM
BTW, there was no damage to the prop. Makes me kinda wonder how the shaft originally bent. :confused:
Since this is the case, I think I'd ask for the old part & verify that it's bent.

jsonova99
03-21-2005, 04:09 PM
I would get it straightened by a machine shop and keep it as a spare in case you ever really damage the current one beyond repair. The least they can do is give you the old one back.

rasmithaz
03-21-2005, 04:39 PM
I know it's too late to help you..... I'm sorry I didn't see your post earlier. When you get your prop shaft back take it to a good engine/machine shop to verify runout. It's real hard to get an accurate reading with the prop shaft is still in the boat....unless it's way out of whack. Then call Glenwood Marine California and see what they charge for a prop shaft. Take a couple deep breaths before you call because he is going to tell you that prop shaft is sold for $117.50 plus frieght. I know we can't have any more group buys but we should be able to help each other out on these type of issues. 1 each- 1" 303 x 47 1/2 OAL. Double Taper- minor Dia= .890- 3/4 x 16 threads on engine end.

team north
03-21-2005, 06:56 PM
skidim has shafts as does elberts (www.elberts.com) and they are about 150-200$ easy to do yourself. if it is out of tolerance you could either snap your shaft or wreck your tranny so it's a small price to pay for preventitive work