How much clearance should there be between motor mount and motor mount bolt? - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Hotrodding Basics
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 06-08-2006, 07:06 PM
Registered User
 

Last journal entry: 63 split window Corvette RESTOROD
Last photo:
Join Date: Dec 2005
Location: Norwalk, Ohio
Posts: 131
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
How much clearance should there be between motor mount and motor mount bolt?

I have what I consider quite a bit of clearance between the motor mount and the motor mount bolt, is this typical?



seems to me that at most there should be a few thousandths, but it is more like 1/4" to 3/8"......thoughts, nothing to worry about? I can just see the motor reving up against those bolts and getting a good chance to run up at it....comments??????

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 06-08-2006, 09:19 PM
Registered User
 
Join Date: Nov 2005
Location: Duffield ,Va
Age: 67
Posts: 526
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
Quote:
Originally Posted by firstgear
I have what I consider quite a bit of clearance between the motor mount and the motor mount bolt, is this typical?



seems to me that at most there should be a few thousandths, but it is more like 1/4" to 3/8"......thoughts, nothing to worry about? I can just see the motor reving up against those bolts and getting a good chance to run up at it....comments??????
You will never know it , if it were in the thousands , you would never get the engine lined up on both sides.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 06-08-2006, 10:35 PM
FEDDO's Avatar
Member
 
Join Date: Mar 2005
Location: middle ga
Posts: 369
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
bolts

Use thick, large washers.
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 06-09-2006, 09:31 AM
Registered User
 

Last journal entry: 63 split window Corvette RESTOROD
Last photo:
Join Date: Dec 2005
Location: Norwalk, Ohio
Posts: 131
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Quote:
Originally Posted by dgcantrellsr
You will never know it , if it were in the thousands , you would never get the engine lined up on both sides.
that is basically what I wanted to hear....thanks!
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 03-20-2013, 08:04 PM
496CHEVY3100's Avatar
Appalachian American
 

Last journal entry: ,
Last photo:
Join Date: Jul 2012
Location: Appalachia GA
Posts: 856
Wiki Edits: 0

Thanks: 484
Thanked 324 Times in 286 Posts
I dont think you have any thing to worr about ,it has to have some clearance .dont use washers or bigger diameter bolts ,the ones you have are much stronger than the rubber bonded to your mount ,just a note i had to change my frame mounts also ,but mine is an 88 it is not a bolt in like everyon said when i started . Good Luck
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 03-21-2013, 09:25 AM
hcompton's Avatar
Old & Furious
 
Join Date: Oct 2012
Location: MD
Age: 41
Posts: 1,074
Wiki Edits: 0

Thanks: 6
Thanked 87 Times in 84 Posts
Is there gap in between the mount and the tang on the engine. Can the engine wiggle back and forth or is it tight fit. I would use washers to tighten the space between the mount and the tube on the engine side of the mount. This should allow you to tighten the bolts down so it doesnt move.

If your looking for smooth ride get stock mounts. Other wise tighten it down so its locked in place. It should lift a fender when it revs not just wobble around inside the engine compartment like a stock engine.
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 03-21-2013, 11:33 AM
MARTINSR's Avatar
Brian Martin,Freelance adviser
 
Last photo:
Join Date: Jun 2004
Location: San francisco bay area
Age: 55
Posts: 13,366
Wiki Edits: 0

Thanks: 1,493
Thanked 1,263 Times in 1,106 Posts
I have to go with the point on fitting the engine. Try putting those bolts thru the mounts when dropping a motor into a 70 Camaro or something like that with the front sheetmetal on and you are laying under the car with it on jack stands. You would be damn happy to have that little wriggle room and it would be perfectly clear why it HAD to be there. If it was a few thousands you would NEVER get that bolt in! There has to be a little room to make up for flaws in the location of the mounts on the frame and motor. There is no way there can be absolute perfection in where those mounts are mounted on every frame in every car, even from the factory. A little sagging of a frame over it's life, different brand mounts, etc, there are way too many variables to ever have a perfect hole for that bolt to go thru.

Use the larger, thicker washers and tighten it up well and there you go.

Brian
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 03-21-2013, 01:47 PM
Registered User
 
Last photo:
Join Date: Apr 2007
Location: Seattle, Wa
Posts: 7,008
Wiki Edits: 0

Thanks: 4
Thanked 508 Times in 431 Posts
Quote:
Originally Posted by firstgear View Post
I have what I consider quite a bit of clearance between the motor mount and the motor mount bolt, is this typical?



seems to me that at most there should be a few thousandths, but it is more like 1/4" to 3/8"......thoughts, nothing to worry about? I can just see the motor reving up against those bolts and getting a good chance to run up at it....comments??????
This makes up for the fact that chassis are really pretty sloppy when it comes to assembly so the stack-up of tolerances requires some give when it comes to the engine and transmission's attachement. They take the adjustment at the engine as that's fewer oversize holes. Once the bolt is torqued the engine isn't going anywhere, so this isn't a problem. If you use a hardened washer between the underside of the bolt head and the mount, it won't distort like a regular washer so it will insure the bolt's clamping force is well and stablely transfered into the mount.

Bogie
Reply With Quote Quick reply to this message
  #9 (permalink)  
Old 03-21-2013, 10:10 PM
Registered User
 
Last photo:
Join Date: Jan 2011
Location: Hopewell, Va
Age: 62
Posts: 1,228
Wiki Edits: 0

Thanks: 0
Thanked 121 Times in 117 Posts
How much clearance should there be between motor mount and motor mount bolt?

Use grade 8 bolts with flat washers and locknuts. The bolts should be 4 1/4 x 7/16.
Reply With Quote Quick reply to this message

Recent Hotrodding Basics posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

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

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 On
Pingbacks are On
Refbacks are On



All times are GMT -6. The time now is 03:52 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.