Go Back  Offshoreonly.com > Technical > Drives and Lower Units
Blew up XR ITS Upper >

Blew up XR ITS Upper

Notices

Blew up XR ITS Upper

Thread Tools
 
Old 09-08-2018 | 12:34 PM
  #21  
Thread Starter
Registered
 
Joined: May 2017
Posts: 44
Likes: 0
From: San Bernardino
Default Update




I was able to get the helmet off, but cannot get the driveshaft out, check out those splines the pinion gear was on. I can’t remember what the gimbal bearing looked like, but I think the inner portion is pushed in.
zx1421 is offline  
Reply
Old 09-08-2018 | 12:40 PM
  #22  
Registered
20 Year Member
 
Joined: Aug 2004
Posts: 430
Likes: 3
From: Whitefish Chain - Crosslake, MN
Default

You're going to need a bigger slide hammer! Those splines are impressive.
ACrooks69 is offline  
Reply
Old 09-08-2018 | 07:10 PM
  #23  
Thread Starter
Registered
 
Joined: May 2017
Posts: 44
Likes: 0
From: San Bernardino
Default

Just to check I’m not crazy. Since I have the lower off, if I rotate it and the prop shaft turns 1 revolution, and the shaft that goes up in the upper rotates 1 and almost 1/4, that means I have 1:24 gear ratio,,,,right? If so , I’m surprised I can turn 32p and 30p props.
zx1421 is offline  
Reply
Old 09-08-2018 | 09:54 PM
  #24  
Tinkerer's Avatar
Registered
20 Year Member
 
Joined: Jan 2002
Posts: 4,612
Likes: 7
From: ALTO, MI
Default

Do the upper gears have the same number of teeth? If not then the upper gears will change the ratio also.
Tinkerer is offline  
Reply
Old 09-08-2018 | 11:35 PM
  #25  
VIP Member
20 Year Member
VIP Member
 
Joined: Nov 2002
Posts: 4,176
Likes: 333
From: ankeny,ia.
Default

Originally Posted by zx1421
Just to check I’m not crazy. Since I have the lower off, if I rotate it and the prop shaft turns 1 revolution, and the shaft that goes up in the upper rotates 1 and almost 1/4, that means I have 1:24 gear ratio,,,,right? If so , I’m surprised I can turn 32p and 30p props.
all XRs are a 16/19 tooth upper, the difference in ratios are determined in the lower, they come in 1.5, 1.35 and a 1.26reduction.....if you have a 17/18 count lower, that would be a 1.26 lower

Last edited by JaayTeee; 09-08-2018 at 11:42 PM.
JaayTeee is offline  
Reply
Old 09-09-2018 | 07:08 AM
  #26  
Thread Starter
Registered
 
Joined: May 2017
Posts: 44
Likes: 0
From: San Bernardino
Default

Well, since I’m not opening it, I can only count rotations, on a differential, this would be the procedure. Since you say the upper is 16/19, it’s not 1:1, but darn close.
zx1421 is offline  
Reply
Old 09-09-2018 | 07:10 AM
  #27  
Thread Starter
Registered
 
Joined: May 2017
Posts: 44
Likes: 0
From: San Bernardino
Default

Well, since I’m not opening it, I can only count rotations, on a differential, this would be the procedure. Since you say the upper is 16/19, it’s not 1:1, but darn close.
zx1421 is offline  
Reply
Old 09-09-2018 | 07:28 AM
  #28  
Registered
15 Year Member
 
Joined: Nov 2009
Posts: 4,198
Likes: 500
From: KY
Default

Ratios
AllDodge is offline  
Reply
Old 09-09-2018 | 12:53 PM
  #29  
Thread Starter
Registered
 
Joined: May 2017
Posts: 44
Likes: 0
From: San Bernardino
Default

I guess what nobody is saying is, since the upper is not 1:1 , you can’t figuer out gear ratio by turning the vertical shaft in the lower and count rotations, you need it together as a unit and turn the driveshaft, and count rotations.
zx1421 is offline  
Reply
Old 09-09-2018 | 01:29 PM
  #30  
Registered
15 Year Member
 
Joined: Nov 2009
Posts: 4,198
Likes: 500
From: KY
Default

No it can be done, by rotating the lower 10 times. Your rotating 10X because it becomes more obvious, then working with small degrees

As example
Upper gears 19/16 = 1.187
Lower gears 15/19 = 0.789

Calculation 1.187/0.789 = 1.504 ratio

So rotate and count
1.26 lower 17/18 = 0.944 10X = 9.44
1.35 lower 15/17 = 0.882 10X = 8.82
1.50 lower 15/19 = 0.789 10X = 7.89

Last edited by AllDodge; 09-09-2018 at 02:30 PM. Reason: removed divide part
AllDodge is offline  
Reply


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2026 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.