Null


engine mounting question. I have bad vibration coming from the drive shaft ?

  • 5 Replies
  • 410 Views

82 baja 460

  • Join Date: Oct 2019
  • *
  • Newbie
  • *
  • Posts: 4
  • Karma: +0/-0
  • Registered User
    • View Profile
  • Liked:
  • Likes Given: 0
« on: October 09, 2019, 03:46:57 PM »
I'm new to this forum and i have an unstoppable passion for my Jet boat... Currently i have a nasty vibration which i think is coming from the drive shaft which is only 6.5" long (hopefully not the motor).  It doesn't have a PTO on the 460, it's mounted directly to the flywheel/crank shaft.  I've replaced the u joints multiple times and i still have a slight mechanical bind of some sort.  I think the yoke is messed up somehow.  I've replaced the thrust bearing and impeller/sleeve already which didn't help.  I've even removed the bowl and impeller to help trouble shoot and eliminate that part of the drive line. I have the splicer kit 1310 on order with the adapter plate for the 460 bolt pattern, but that makes the drive shaft 2" longer at 8.5" total.  How can i support the rear part of the motor now? it was mounted on the bearing block assembly before.  Also I've had a hard time trying to get the motor mounted at the correct angle.  My understanding is that the engine should be about 1 to 2 degrees off not straight on.  With that said, the oil pan drain plug area hits the bottom of the boat.  I've had this boat for about 1.5 years now and I've replaced the stringers, floor and interior last winter.  It ran great for the first month then i noticed a slight vibration which turned really bad really quick.  Any guidance would be appreciated thanks. (Ford 460 big block with a Berkeley 12JE)


Null


GT Jets

  • Join Date: Jan 2007
  • Location: Morgan Hill CA
  • *
  • Informative Member
  • *******
  • Posts: 11,752
  • Karma: +192/-0
  • Team Evil Weiner
    • View Profile
  • Liked:
  • Likes Given: 138
« Reply #1 on: October 10, 2019, 10:46:19 PM »
I'm new to this forum and i have an unstoppable passion for my Jet boat... Currently i have a nasty vibration which i think is coming from the drive shaft which is only 6.5" long (hopefully not the motor).  It doesn't have a PTO on the 460, it's mounted directly to the flywheel/crank shaft.  I've replaced the u joints multiple times and i still have a slight mechanical bind of some sort.  I think the yoke is messed up somehow.  I've replaced the thrust bearing and impeller/sleeve already which didn't help.  I've even removed the bowl and impeller to help trouble shoot and eliminate that part of the drive line. I have the splicer kit 1310 on order with the adapter plate for the 460 bolt pattern, but that makes the drive shaft 2" longer at 8.5" total.  How can i support the rear part of the motor now? it was mounted on the bearing block assembly before.  Also I've had a hard time trying to get the motor mounted at the correct angle.  My understanding is that the engine should be about 1 to 2 degrees off not straight on.  With that said, the oil pan drain plug area hits the bottom of the boat.  I've had this boat for about 1.5 years now and I've replaced the stringers, floor and interior last winter.  It ran great for the first month then i noticed a slight vibration which turned really bad really quick.  Any guidance would be appreciated thanks. (Ford 460 big block with a Berkeley 12JE)
Your information is flawed?

The engine should be nearly dead nuts with only a slight parallel offset. ANY difference in final angle will play havoc with harmonics and driveline vibration.
The parallel offset should not net more that a degree of joint deflection, but not less than 1/2 a degree for joint bearing lubrication and dynamic tightening.



Sent from my LG-H872 using SoCal Jet Boats mobile app

  • Boat #1: 1992 Carrera 20.5 Elite (I/O bitches)
  • Boat #2: 19' Bubble deck Jet BBC Berkeley
If i get some free time tonight at work, ill play with it and post it for everyone to see.

Time to man up and yank it John!  :banghead:
Ray

82 baja 460

  • Join Date: Oct 2019
  • *
  • Newbie
  • *
  • Posts: 4
  • Karma: +0/-0
  • Registered User
    • View Profile
  • Liked:
  • Likes Given: 0
« Reply #2 on: October 11, 2019, 02:25:16 PM »
thanks for the info.  I'll have to remove the oil pan and get it modified so I can get that .5 - .9 degree angle so it's not crashing into the bottom of the boat.  Hopefully next few weeks I'll be able to finish it up and test it out.

Flusher

  • Join Date: Sep 2011
  • Location: Colton, CA
  • *
  • Macho Member
  • ******
  • Posts: 2,121
  • Karma: +81/-0
  • The Machinist
    • View Profile
  • Liked:
  • Likes Given: 26
« Reply #3 on: October 11, 2019, 04:02:17 PM »
You shouldn't have to modify the oil pan, unless it is deeper than 8 inches.
"I want to roll with my brother Joe" - Joe Bateman - January 29, 1950 ~ November 27, 2013

82 baja 460

  • Join Date: Oct 2019
  • *
  • Newbie
  • *
  • Posts: 4
  • Karma: +0/-0
  • Registered User
    • View Profile
  • Liked:
  • Likes Given: 0
« Reply #4 on: October 12, 2019, 12:44:13 PM »
Yes for whatever reason it's at 8.66" and it looks like a Dorman oil pan part# 264-07.  What should the original pan height be?

motocam360

  • Join Date: Sep 2019
  • Location: seattle
  • *
  • Newbie
  • *
  • Posts: 13
  • Karma: +0/-0
  • Registered User
    • View Profile
  • Liked:
  • Likes Given: 0
« Reply #5 on: October 20, 2019, 11:13:09 AM »
Post up some pictures of your setup so we can help.

I've got an F460 with 12JE setup, Milodon 8" 10qt pan, 4 point mounting system and everything lines up nice (except my exhaust to transom ports).

 


Website Security Test
Powered by EzPortal

Null

Website Security Test