Go Back  Offshoreonly.com > Technical > General Q & A
Help Finding Drive Shaft Centerline >

Help Finding Drive Shaft Centerline

Notices

Help Finding Drive Shaft Centerline

Thread Tools
 
Old 06-26-2020 | 09:38 AM
  #1  
BDiggity's Avatar
Thread Starter
Registered
 
Joined: Feb 2005
Posts: 1,801
Likes: 33
From: Palm Bay FL
Default Help Finding Drive Shaft Centerline

I am trying to figure out a way to determine what my propshaft depth would be for new drives based on current engine height. My thought was if i knew the current TRS drive shaft centerline, i could then take measurements off this point for new drive. I cant find any TRS drawings with the measurements, so does anyone know what the drive shaft centerline measurement is in relation to the transom cutout? In pictures it looks like its about 4" or so from the top, or maybe in the center of the very top & bottom assembly bolts. But would like something more accurate than my eyeing of internet pics. Engines are out of boat & drives at shop. So the only reference point i have right now is the outline of the transom cutout.

I already know i will need to move the engines back, so now curious if i will need to change the engine mount height too.
BDiggity is offline  
Reply
Old 06-26-2020 | 09:49 AM
  #2  
Registered
20 Year Member
 
Joined: Aug 2003
Posts: 1,129
Likes: 32
From: Racine, Wisconsin
Default

TRS input shaft to prop shaft centerlines is about 24.5 inches.
kvogt is offline  
Reply
Old 06-26-2020 | 12:47 PM
  #3  
Griff's Avatar
Charter Member # 55
25 Year Member
Charter Member
Super Moderators
 
Joined: Oct 2000
Posts: 20,232
Likes: 2,482
From: Omaha/LOTO
Default

What drives are you going with??
Griff is offline  
Reply
Old 06-26-2020 | 01:23 PM
  #4  
BDiggity's Avatar
Thread Starter
Registered
 
Joined: Feb 2005
Posts: 1,801
Likes: 33
From: Palm Bay FL
Default

Originally Posted by kvogt
TRS input shaft to prop shaft centerlines is about 24.5 inches.
Right. But that in itself doesnt tell me where the input centerline is in relation to the drive cutout. If i knew all TRS Cafe's had propshaft at lets say 5.5" below hull, then yes i could measure up 24.5" to find input centerline, & then measure down again for the new drive length.

I just dont have any hull reference right now to know where to start my measurements. If that makes sense. lol.

Reason i am curious is i thought i was buying a pair of Konrad 540 PRS's as direct TRS replacements. What i received was a pair of ACE drives which are meant for Bravo replacements. I actually like the ACE package better since it has built in steering & extension boxes. And since i have a fresh transom without any cutouts, it wont take much more effort to use these drives. So i know i will need to move the engines back, & now just want to get an idea of the height change the engine will need.


BDiggity is offline  
Reply
Old 06-26-2020 | 01:53 PM
  #5  
BDiggity's Avatar
Thread Starter
Registered
 
Joined: Feb 2005
Posts: 1,801
Likes: 33
From: Palm Bay FL
Default

Originally Posted by Griff
What drives are you going with??
A used pair of Konrad ACE's. They were delivered Mon & i only had time to move them into the shop. But from my initial viewing they look much more massive than my TRS- especially with those extension boxes. i will be back out at shop this weekend so thats why i wanted to try & get idea of my engine placement.
BDiggity is offline  
Reply
Old 06-26-2020 | 05:08 PM
  #6  
VIP Member
20 Year Member
VIP Member
 
Joined: Nov 2002
Posts: 4,176
Likes: 333
From: ankeny,ia.
Default

Are the new drives shorter than the TRS’s?.... with the boxes you’re going to want them higher than they were originally
JaayTeee is offline  
Reply
Old 06-26-2020 | 07:00 PM
  #7  
BDiggity's Avatar
Thread Starter
Registered
 
Joined: Feb 2005
Posts: 1,801
Likes: 33
From: Palm Bay FL
Default

Originally Posted by JaayTeee
Are the new drives shorter than the TRS’s?.... with the boxes you’re going to want them higher than they were originally
I believe the regular lower is 1.7" shorter than TRS. I am pretty sure that's what is on them. Tomorrow I plan on getting the measurement to verify standard or shorty. Then the fun part of figuring out where my props should be, exhaust & transmission changes...
BDiggity is offline  
Reply
Old 06-27-2020 | 01:36 AM
  #8  
Griff's Avatar
Charter Member # 55
25 Year Member
Charter Member
Super Moderators
 
Joined: Oct 2000
Posts: 20,232
Likes: 2,482
From: Omaha/LOTO
Default

What you really need to find is what is the X dimension set at on the Cafe's with Bravos.
Then raise it another inch up for the ext boxes.
Then determine the difference in depth of the Konrad vs Bravo.
Griff is offline  
Reply
Old 06-27-2020 | 05:57 AM
  #9  
VIP Member
20 Year Member
VIP Member
 
Joined: Nov 2002
Posts: 4,176
Likes: 333
From: ankeny,ia.
Default

Does it have a notched transom ?

if not, you might try to get a hold of Carter and see if he has any info on the set up of this unit
as to where the prop shaft depth Is
https://www.offshoreonly.com/classif...35-o77771.html
JaayTeee is offline  
Reply
Old 06-27-2020 | 07:00 AM
  #10  
Registered
15 Year Member
 
Joined: Jul 2007
Posts: 3,333
Likes: 852
Default




Originally from Full Force thread I believe.......I don't have a drawing from a TRS but the numbers seem to correlate from Image 1 to the SSM drawings as a visual aid

F.F. may have the actual drawing if you PM him

Last edited by speicher lane; 06-27-2020 at 07:05 AM.
speicher lane 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.