Which direction does the motor move on mounts under power? - Vintage Mustang Forums
Vintage Mustang Forum
HomeForumGalleryClassifiedsAbout UsAdvertiseContact Us
» Auto Insurance
» Featured Product
Go Back   Vintage Mustang Forums > General Discussion > Vintage Mustang Forum
Vintage-Mustang.com is the premier Ford Mustang Forum on the internet. Registered Users do not see the above ads.
Reply
 
Thread Tools
Old 08-26-2003, 09:01 PM   #1 (permalink)
Senior Member
 
Join Date: Aug 2002
Location: Laplata, MD
Posts: 1,068
Default

Which way does the motor rotate on mounts in reverse? Moving forward, motor lifts the drivers mount and compresses passenger mount, just the opposite in reverse? Trying to diagnose a shake when starting out in reverse.
__________________
1966 Shelby GT350 6S383 Paxton Blower and T5Z
1968.5 R-Code FB, Zero option, 4-speed 4.30 rear, radio delete car
2006 Viper Coupe w/ Paxton
2010 Custom Harley Street Glide
johnk is offline   Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Old 08-26-2003, 09:09 PM   #2 (permalink)
Senior Member
 
johnpro's Avatar
 
Join Date: Jul 2000
Location: Roseville, California
Posts: 25,242
Default

The pressure will mostly be on the passenger side motor mount (that's the one that will usualy brake). The motor spins counter-clockwise (sitting from the driver's seat) so the motor is going to naturally want to roll over onto the driver's side inner fender.

__________________
VMF Jedi Knight who's spirit will be with us forever.
johnpro is offline   Reply With Quote Quick reply to this message
Old 08-26-2003, 09:28 PM   #3 (permalink)
Supporting Member
Just some guy
 
GypsyR's Avatar
 
Join Date: Jun 2001
Location: SC foothills, USA
Posts: 12,205
Default

You've got it. In reverse you're "stretching the right motor mount. One of my trucks has a tendency to break the passenger side motor mount when I try to back up a steep hill while loaded. 5 times so far. Never a problem in forward gears and I believe the driver's side mount is original to the the truck. Weird.
__________________
11. If thou be not absolutely sure of thy facts, thou shalt Google before posting thine answer.
GypsyR is offline   Reply With Quote Quick reply to this message
Old 08-26-2003, 09:36 PM   #4 (permalink)
Senior Member
 
johnpro's Avatar
 
Join Date: Jul 2000
Location: Roseville, California
Posts: 25,242
Default

GypsyR, I'm sure you didn't mean it this way, but it almost makes it sound that the engine spins in the opposite direction in reverse You're ALWAYS stretching the passenger side motor mount, wether the car's going forward or backwards (and the reason most people will only put a torque strap on the passenger side).
__________________
VMF Jedi Knight who's spirit will be with us forever.
johnpro is offline   Reply With Quote Quick reply to this message
Old 08-26-2003, 09:43 PM   #5 (permalink)
Senior Member
 
66benchcoupe's Avatar
 
Join Date: Jul 2000
Location: Deer Park, CA
Posts: 3,514
Default

Hmmm. . . I've had a few mount break on me and it's always been the drivers side. Watch which way the engine pulls when you rev it. And all the torque straps I've seen are on the drivers side. . .
__________________
http://pic20.picturetrail.com/VOL160...3/69706405.jpg
1966 Coupe
1991 GT
66benchcoupe is offline   Reply With Quote Quick reply to this message
Old 08-26-2003, 10:09 PM   #6 (permalink)
Senior Member
 
Poppy65's Avatar
 
Join Date: Mar 2001
Location: Richmond,VA
Posts: 564
Default

Driver's side. If you unbolt the mount or have a broken driver's side mount the engine will lift on the driver's side....been there done that many, many times. That is why you see the Torque straps used on the driver's side only.
__________________
http://www.shockomedia.com/car/mustang.jpg
Chris Hunter
65 A-Code Convertible
My game site http://www.toadgames.com
Poppy65 is offline   Reply With Quote Quick reply to this message
Old 08-26-2003, 10:28 PM   #7 (permalink)
Supporting Member
Just some guy
 
GypsyR's Avatar
 
Join Date: Jun 2001
Location: SC foothills, USA
Posts: 12,205
Default

Dunno, might have something to do with reverse being geared lower or something. All I really know for sure is the mount always breaks when I'm reversing, even lightly loaded.
Contrast this to stopping on a hill with a loaded car trailer behind it. Never a problem.
Though the engine always rotates in the same direction, the force transmitted to the driveshaft, rear end, and then the chassis is reversed when backing up.
__________________
11. If thou be not absolutely sure of thy facts, thou shalt Google before posting thine answer.
GypsyR is offline   Reply With Quote Quick reply to this message
Old 08-26-2003, 11:17 PM   #8 (permalink)
Senior Member
 
Join Date: Aug 2002
Location: Laplata, MD
Posts: 1,068
Default

This is how I see it. The reciprocating mass internal to the engine tends to press down on the passenger mount when the car is sitting still and engine reved. The motion is compounded by an order of magnitude in forward when the motor/trans is trying to spin the driveshaft and all behind it. Only when there is an oposing load does the motor build its 300, 400, 500 ft-lbs of torque really twisting the motor. However, when in reverse, spinning the driveshaft in the opposite direction easily overpowers the internal engine torque and tends to rotate the engine in the oposite direction, compressing the drivers mount. You don't see engine torque straps on the passenger side of race cars because the serious torque is there only in forward. Years ago my wifes Oldsmobile broke a mount. Never knew it when driving until one day when changing the oil, I backed the car up with the hood up and saw the motor raise about 3 inches on one side. Putting it in forward compressed the bad mount and the motor didn't move.

camachinist, you out there?
__________________
1966 Shelby GT350 6S383 Paxton Blower and T5Z
1968.5 R-Code FB, Zero option, 4-speed 4.30 rear, radio delete car
2006 Viper Coupe w/ Paxton
2010 Custom Harley Street Glide
johnk is offline   Reply With Quote Quick reply to this message
Old 08-26-2003, 11:45 PM   #9 (permalink)
Senior Member
 
66gt350's Avatar
 
Join Date: Jul 2000
Location: Redding, CA
Posts: 1,882
Default

I think that you have that backwards...IIRC the driver's side motor mount is getting stretched and normally will break. The old white race car had the torque strap on the drivers side.
__________________
-Rob "Ricky Bobby"
No one is listening to you, until you fart.

Then________________________________And now
http://moostangproductions.com/66gt350/engine1.jpghttp://moostangproductions.com/66gt350/engine.jpg
66gt350 is offline   Reply With Quote Quick reply to this message
Old 08-26-2003, 11:52 PM   #10 (permalink)
Senior Member
 
Join Date: Aug 2002
Location: Laplata, MD
Posts: 1,068
Default

66gt350, did you see my second post?
__________________
1966 Shelby GT350 6S383 Paxton Blower and T5Z
1968.5 R-Code FB, Zero option, 4-speed 4.30 rear, radio delete car
2006 Viper Coupe w/ Paxton
2010 Custom Harley Street Glide
johnk is offline   Reply With Quote Quick reply to this message
Old 08-27-2003, 12:00 AM   #11 (permalink)
Senior Member
 
Join Date: Jul 2000
Location: Central California
Posts: 10,427
Send a message via ICQ to camachinist Send a message via AIM to camachinist Send a message via Yahoo to camachinist
Default

Equal and opposite....that's the easiest way to remember.

If you know the driver's side of the engine wants to lift going forward, then the opposite will be true when in reverse. It's how and in which direction the power is put to the ground which makes the difference.

Try observing your rear end housing when loading it in forward and reverse gear; it will be readily apparent what I am talking about.

Regarding your shaker, examine all engine mounts and the transmission mount carefully. Also, loosen and re-tighten to spec all pertinent fasteners. If any parts need to be replaced (bad mounts), replace all as a unit if none have been replaced very recently. A failing mount can precipitate cascade stress on the other parts, depending on how the vehicle is operated.

Johnpro likely was tired after a long day or had another sleepless night with his friends with badges and guns *G*
__________________
Visit my VMF lingo page
Visit the Ford engine torque specs page
Visit my MySpace Blog
camachinist is offline   Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Vintage Mustang Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
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.



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 On
Trackbacks are On
Pingbacks are On
Refbacks are Off


Powered by vBadvanced CMPS v3.2.2

All times are GMT -4. The time now is 05:35 AM.


Powered by vBulletin® Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
SEO by vBSEO 3.3.2 ©2009, Crawlability, Inc.