Bedplate torque questions -

LinkBack Thread Tools
post #1 of 6 Old 05-22-2012, 11:17 PM Thread Starter
Registered User
Join Date: May 2012
Location: Virginia Beach
Posts: 4
Bedplate torque questions

Hi everyone,
Im assembling a 4.7 from a 99. Having troubles for some reason. My machine shop told me that their torque specs for the inner bolts are 25ft lbs + 90.

As well as I have heard of multiple people tightening to that spec. However, when I tighten to 25ft lbs it spins, but the extra 90 makes it too tight to spin. The weird thing is that the bearing clearances tightened to that torque are .0015.

So my question is should i use the new rod bolts i have coming and torque to 25in lbs + 90 or should i take the block back to machine shop and have it checked and assemble at the torque that seems correct 25 ft lbs.


325issguy is offline  
Sponsored Links
post #2 of 6 Old 05-22-2012, 11:34 PM
Registered User
1986 CJ7 
Join Date: Dec 2007
Location: Denver Colorado
Posts: 1,878
Are you tighting them to 25ft lbs and then to 90 ft lbs?, Or to 25ft lbs and the a 1/4 trun? Check this out
1986cj is offline  
post #3 of 6 Old 05-23-2012, 12:02 AM Thread Starter
Registered User
Join Date: May 2012
Location: Virginia Beach
Posts: 4
Yea im doing 25 ft lbs then 1/4 turn. I can do them all to 1/8 turn it seems then she locks up as soon as I tighten the last 1/8. So it is verified that you should tighten the inner bolts to 25 ft lbs instead of inch lbs?
325issguy is offline  
post #4 of 6 Old 05-23-2012, 02:27 AM
Registered User
1992 XJ Cherokee 
Join Date: Oct 2007
Location: Rosamond, CA
Posts: 652
The referenced enginebuilder article said 25 INCH-pounds, but that is probably a typo. I can't imagine 25 in/lb + a quarter turn would be enough for main bearings.

But here is one idea: how are you supporting the engine? Is it bolted to an engine stand by the flywheel end? The block might be sagging. Try taking it off the stand and setting it on the workbench, then torque the bolts. I know it sounds crazy, but I once had the same problem with a Mercedes inline-6 block. Block was bolted to the stand, crank would turn just fine until the main caps were torqued. Then it was locked up solid. Took block off the stand, set it on the bench, torqued the main bolts and everything was fine. Yes, cast iron will bend...

The road goes on forever, the party never ends....
wgirvine is offline  
post #5 of 6 Old 05-23-2012, 04:49 AM Thread Starter
Registered User
Join Date: May 2012
Location: Virginia Beach
Posts: 4
Thanks man,
Now that I think of it that is alot of weight sagging down on the engine.
Thanks I will give that a try!
325issguy is offline  
post #6 of 6 Old 06-03-2012, 12:18 PM Thread Starter
Registered User
Join Date: May 2012
Location: Virginia Beach
Posts: 4
Well it still binds up when on the bench. Just got some telescoping gauges and a micrometer set so I am heading out there in a bit to take some measurements and see if everything checks out.
325issguy is offline  

Quick Reply

Register Now

In order to be able to post messages on the forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.

Email Address:


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page

Similar Threads
Thread Thread Starter Jeep Forums Replies Last Post
Torque? malibubts Fabrication Shop 13 02-15-2009 03:50 PM
more torque wheelerbob Engines & Drivetrain 5 10-31-2007 05:04 PM
dry torque versus wet torque frankiefire702 General Jeep & Off-Road Equipment 2 09-27-2007 06:20 AM
help me with torque!! pygocentrus Engines & Drivetrain 2 08-31-2003 07:33 PM
torque ?? Durbahn Tires & Wheels 1 07-27-2003 02:33 PM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome