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Motor Mount Replacement Write-Up

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Old 12-03-2002, 08:47 PM
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Arrow Motor Mount Replacement Write-Up

Ok, the new motor mounts are in and boy were the old ones shot. Here's something I hope you guys will find useful. I dreading taking the steering u-joint off, so found a way around it. Hope this helps!

I used jacks and pieces of wood to support the engine, but you could make an engine hoist like Danno, Ribs, and some of the other folks on this board.

Prior to doing the job, if you have the updated motor mounts, pick up 4 new M8 x 40mm 1.25 pitch bolts in case the old ones break (like mine did).
Spraying the old bolts with some lubricant and letting them soak might be a good idea too.

Please make sure your car and engine is fully supported prior to getting under there. This procedure is just what I did, so proceed at your own risk.

1.Put the rear of the car on ramps or jackstands (levels the car out for more room when the front is raised). Loosen the front lug nuts.
2.Jack up the front of the car and support with jacks – the frame rails are a good spot. I put a second set of jackstands under the front jacking points just in case. Remove the front wheels.
3.Remove the belly pans.
4.Drop the front sway-bar via the drop-links at the control arms and remove both center bushing-holder brackets from the body of the car.
5.Use a marker or sharp object and mark the position of the rear A-arm mounts. This will save you an alignment job (send me the money you save ).
6.Remove the two bolts that hold on the rear A-arm mounts and remove the one bolt at the front A-arm mount. I threaded the bolts back in the holes so they wouldn't be lost.
7.Rotate the A-arms out of the way and support them with a box, tall spray paint can, or whatever so the ball joints aren't damaged.
8.Remove the alternator cooling duct for extra room to get at the driver's side motor mount.
9.Remove the 10mm nuts that are inside the crossmember which hold the clamps for the hard power-steering return line. These bolts can be seen when you're lying on your back and looking up at the bottom of the crossmember.

***Addendum - Remove the bolt on the steering rack that holds the ground wire which leads to the crossmember. Remember to connect this during assembly or your car will very poorly, if at all.***

10.Remove the c-clamps that hold the ps rack onto the crossmember (4 - 13mm bolts). Support rack with a box, jackstand, etc. so the fluid lines are not damaged.
11.Support the oil pan with a jack and piece of wood that spans the width of the oil pan.
12.Support the bell housing with a piece of wood and a jack.
13.Remove the motor mount heat shields.
14.Loosen and remove the nuts at the bottom of both motor mounts. They are under the crossmember directly beneath each motor mount.
15.Loosen and remove all 4 of the 13mm motor mount bolts. I used a regular 13mm wrench and a stubby for this, depending on the space to work with. If they're on tight (I broke one bolt), try spraying some lubricant on them and then try this:
a) put a 13mm stubby on the bolt
b) hook the open end of a longer
combination wrench (19mm or more)
onto the free end of the stubby
c) put a long extension or pipe
through the box end of the combo
wrench and twist. I had a helper
(Thanks Joe) hold down the 13mm
stubby so that it was square
with the bolt.

16.Loosen the 4 bolts that holds the crossmember on. Take a look to see the motor is not dropping with the crossmember.
17.When you are certain that the motor is being fully supported by the jacks, remove the 4 bolts and drop the crossmember.
18.Replace the motor mounts with your new ones and lift the crossmember into place.
19.Partially thread the 4 bolts of the crossmember into the car so that there is room to wiggle the motor mounts into position.
20.Partially install the motor mount bolts and then fully tighten the crossmember bolts to spec.
21.Tighten the motor mount bolts to spec and install the lower bolts for each motor mount.
22.The rest is the reversal of the above steps.

* When trying to install the A-arms back to the marked position, it is useful to have someone install the bolts while you hold the A-arms in position.
Old 12-03-2002, 09:10 PM
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RJP 951
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How long did this job take? Was this your first attempt? I know I need motor mounts but figured it was one job I'd pay to have done. With a procedure like this in hand, I'm tempted to reconsider and do it myself.

Thanks for taking the time to document this.

Ron
Old 12-04-2002, 09:29 AM
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Are you sitting down? This was my first time doing the job on this car or any car, and it took me 12+ hours over 2 days. However, that included time to eat, watching my friend's digital cable t.v. , cleaning parts, and staring at my oil leak. I also helped him out with his car as well.

So if you were to do it non-stop, figure maybe 6-8 hours. Just take your time.

It's not that hard, and believe me when I say I was apprehensive about doing this myself.

Now I feel like taking the engine out of the car!
Old 12-04-2002, 03:34 PM
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Holy cow! I thought it took me too long because it took me 4-6 hours That included several minutes of stomping around the garage bitching because the rear bolt on the exhaust side mount wouldn't come out. Nothing a little careful grinding couldn't fix.

Also, I don't understand why you had to drop your steering rack off of the crossmember. There should have been plenty of play in the steering linkage and fluid lines to allow you to yank the mounts without dropping the rack.

Regarding the rack-to-crossmember ground, when I replaced my rack with a manual rack I left the ground disconnected for a little while (well, actually I broke the wire) and the only thing that happened was the horn stopped working. As soon as I got around to replacing the wire the horn worked fine.

Also, and this is not ideal by any stretch of the imagination, you can replace the left side mount without dropping the cross member or a-arm. However, you should only do this, in my opinion, as a quick fix to get the car on the road as it is really difficult to torque the lower mount nut properly. Let's just say I had to employ this technique because of a Sears Crapsman torque wrench:

1) Raise the front end and chock the rear wheels.
2) Remove the left front wheel.
3) With much cussing and knuckle banging, loosen and remove the lower left motor mount bolt. You will need to use an open end wrench or if you hold your jaw just right you can wiggle a socket on a union into place and break the nut free.
4) Support the motor under the oil pan and bell housing, but just. Don't lift at all.
5) From above, break loose the two upper bolts on the motor mount.
6) Loosen and remove the four bolts holding the motor cradle to the block and pull the cradle free. Again, make sure the motor is supported but not lifted.
7) With the cradle removed, lift out the motor mount and replace it with a new one. You may want to attach and properly torque the mount to the cradle and lower it into place as a unit.
8) Reattach the cradle to the block and torque the four bolts that hold it in place. You may need to adjust the support under the motor to get the bolts to line up.
8.1) if you haven't already, torque the two upper bolts that hold the motor mount to the cradle
9) Here is the bitch, install and tighten the nut onto the lower stud on the motor mount. It is a real PITA to get at as you may have noticed earlier and hard to torque properly. If you have to you can drop the front end of the control arm to get to and torque the bolt.
10) reinstall the wheel and lower the car.

Again, this is not ideal and I hope you don't have to employ this method, but it did cut a ****pile of time off replacing this one mount.
Old 12-04-2002, 08:27 PM
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If I thought I could do this in 12 hours over a weekend I'd be pretty pleased. Congratulations. Now I've got to decide if I should take the plunge.

Thanks
Ron



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