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poly motor mounts how do you install?

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Old Mar 30, 2004 | 07:50 AM
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Default poly motor mounts how do you install?

ok my engine is out, i got the motor mounts off.
but how do you get the poly mounts inside the "clam shell"..... er things that hold the ruber or poly inside
or see the mount in the picture


the clamshell seams to be riveted and welder or something how do you open it up or slide it out?
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Old Mar 30, 2004 | 07:57 AM
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You have to drill the rivets out. Take the clam shell off of the block and drill the rivets and usually the mounts come with bolts to put it back together.
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Old Mar 30, 2004 | 08:10 AM
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ok thanks found it also by searching
http://www.humanoidms.com/howtos/polymount.doc

Well, I just got done installing the driver's side mount and thought I would provide some feedback for others doing the same thing. For reference I have a 2000 SS with Grott 1-3/4" LT's, stock K-member, and stock steering rack. This was the Prothane LS1 poly mount p/n 7-512-BL (black) I got from Thunder Racing.

Removal order went like this:
1) Disconnect battery
2) Raise front of vehicle on jack stands
3) Remove serpentine belt
4) Remove alternator (3 bolts, 2x15mm and 1x13mm)
5) Remove engine mount heat shield mounted to motor mount-to-block attach bracket (2 bolts, 10mm)
6) Place jack under oilpan to support engine while motor mount is out
7) Loosen the motor mount through bolt
8) Jack up engine slightly to relieve load on the through bolt.
9) Remove through bolt.
10) Loosen and remove bolts holding "pedestal" bracket onto K-member (4 bolts, 15mm)
11) Loosen and remove bolts holding motor mount to engine block (4 bolts, 13mm)
12) Slide engine mount "clamshell" out.
13) Drill out 2 rivets and 3 press rivets from clamshell and remove the stock rubber insert. As slick98ta mentioned, the rubber insert is bonded to the metal so you have to work at it some. The Prothane instructions say to use a torch to heat the rubber for removal, but I just pried it loose. Make sure you clean up the excess rubber crap that gets left behind. I just used an X-acto knife.
14) Insert the poly mount in the clamshell. The Prothane setup has you install 4 3/8" bolts (included with the mounts) where the rivets used to be to bolt the clamshell back together. Torque those to 30 ft-lb (per instructions).
15) Installation is the reverse order.

Torque specs (from my 2000 Helms Manual) are as follows:

- "pedestal" bracket-to-K-member bolts - 43 ft-lb
- engine mount bracket-to-block bolts - 37 ft-lb
- engine mount through bolt - 70 ft-lb
- engine mount through bolt nut - 59 ft-lb
- engine mount heat shield nuts - 89 in-lbs
- forward alternator mount bolts - 37 ft-lbs
- rear alternator mount bolts - 18 ft-lbs

* Note that I didn't have to remove the Grott header or the steering linkage (although doing so would have made it much easier I think).
** Also the Prothane mount fit perfectly - no washers needed. Just make sure you get the 7-512 part number.
Anyway, I took the car for a test drive and the Y-pipe banging is notably improved. I still get a "tap" on a hard shift with the Ram 910 clutch, but no more banging on clutch chatter, etc., like before. Since I'm running cats too I have almost zero clearance on my Y-pipe. If you have 1/2" clearance or so I imagine this would eliminate any banging. Car idles smoother now too. I feel some more vibration through the chassis, but overall car feels smoother (this is with hotcam idle) and shifter hardly moves now.

Overall I would say a very nice improvement. Figure about 3-4 hours if you take your time. Hope this helps.

Now I'm going to work hard at reducing my supply of Bud Light

EDIT: Updated to add passenger side info

I've been very happy with the driver's side only Prothane mount, but decided I wanted to install the passenger side also. I just got finished doing that this evening and I wanted to update this post. The process for the passenger side is basically the same as the driver's side except that the A/C compressor needs to be removed first. This goes as follows (assuming vehicle is already on jackstands):

1) Remove A/C belt from below.
2) Remove 4 bolts (15mm) attaching A/C compressor to mounting bracket. The top two you'll have to get from above and the bottom two bolts from below. Once the compressor is loose just push it forward as far as you can - the swaybar makes a good resting place. Make sure you unplug the electrical connector to get some additional clearance.
3) Remove 4 bolts (15mm) attaching A/C bracket to engine block. You can get all of these bolts from below once the compressor is out of the way.

At this point you have the necessary access to the motor mount brackets. Just remove and install as noted above for the driver's side. The service manual tells you to remove the starter as well, but I didn't have to do that. Maybe this is necessary with the stock exhaust manifolds or if the motor mount through-bolt is installed from the rear for some reason.

Installation is reverse order.

Torque specs (from my 2000 Helms Manual) are as follows:

- "pedestal" bracket-to-K-member bolts - 43 ft-lb
- engine mount bracket-to-block bolts - 37 ft-lb
- engine mount through bolt - 70 ft-lb
- engine mount through bolt nut - 59 ft-lb
- A/C compressor bracket-to-block bolts - 37ft-lbs
- A/C compressor-to-bracket bolts - 37 ft-lbs

Haven't had a chance to drive it yet (the weather sucks here right now), but will update again with first impressions.
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Old Mar 30, 2004 | 06:22 PM
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that way is alot harder, when i did mine i jsut had to take out the starter
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Old Mar 31, 2004 | 12:40 AM
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Thanks for the details 'SmokinHawk' as I have the same Part# and will be installing these while I am in there installing my QTP SS LT's and catted Y along with a few more goodies...
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Old Mar 31, 2004 | 09:22 AM
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when i did mine i just pulled the starter after the exhasut was out, i was doin headers, and then tok them out after supporting the underside of the motor with a jack and a piece of wood.
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