New rear motor mount and alternator brushes

[sdpatt]

I had a successful morning working on my own SHO. I was finally able to get the correct brushes to replace the original set still in my 256,365 mile-old alternator. The removal and replacement went smoothly but it would have been much simpler to just install a new alternator. Well, I don't have a job, so a $9.99 set of brushes made better economic sense to me. You can see from the photo below that there was a great deal of the old brushes worn away. The braided copper lead was not long enough to let the brush firmly contact the commutator. Now there is no more battery light after hot startups before the revs top 1500 rpm.

I had replaced the front mount a couple of weeks ago and was able to get Ford to sell me the rear mount at a 30% discount. This job is somewhat simpler than the front mount in that you don't have to drain the radiator. I did have to unbolt the cat-back ******, the engine roll damper on the strut tower and the front mount bolt at the subframe. After pulling the old mount out, I was shocked (well, not really) to see that the steel cradle was completely separated from the rubber insulator. You can see my fingers stuffed in the gap between the two parts. The rear mount already has a reinforcing bolt installed to prevent the engine from completely lifting in reverse should the bond between the steel and rubber fail. With the new mount, the engine is much more solid and smoother on shifts and when I let off the throttle. It will probably also be better off when I try to back the boat into its parking place in my back yard.

Alternator disassembled

Old and new brushes

Old and new mounts

Total separation of old mount

Reinforcing bolt in old stock mount

<small>[ March 16, 2002, 04:44 PM: Message edited by: sdpatt ]</small>

 

[Bizzy]

Yay Scott! Now would you please come to Michigan??

I still haven't done mine, I expect my mount will be in one of these days soon. Next weekend is our first meet so that's out of the question so the following weekend should be the big mount weekend for me...weather permitting.

 

[Shoman594]

I guess that is true then when the front one goes the rear one goes. I have fixed motors and stuff with replacing the brushes, you can save your self so much money by doing that. Scott how hard was it to take apart the alternator ?

P.S nice pics... interesting

 

[SHOfun 93]

Scotty,
Nice work. I see those ever familiar blue gloves are still at work...glad the motor is sound in where it needs to be once again...one million miles...here we come... thumbs_u

 

[sdpatt]

Shoman594, I have replaced the front mount three times, but that was the first replacement for the rear mount.

The 90A Mitsubishi alternator on this 1991 SHO was a piece of cake for this old Radio Shack kit kinda guy. Once you have the alt off the car, there are four 8mm bolts that hold the two case halves together (long bolts at top left of first photo). To get the stator windings out, you remove the three phillips headed screws that hold the rectifier to the rear case. I unsoldered the two solid connections from the brush holder assembly to the rectifier to get it clear for easier work. To remove the brushes, there is a small plastic cap on the outboard end of the brush holder that covers the leads. It is just pressed in place, pull it off. The brush leads can then be unsoldered and the brushes removed from the bore side. The new brushes are inserted with the springs and the leads soldered in place. It took a couple of tries to get the leads at the proper configuration to allow the brushes to travel all the way down the bore as they wear out. The plastic cap is then replaced and the brush assembly resoldered to the rectifier. An unfolded paper clip is inserted through the hole in the brushes and the rear case to hold the brushes in the retracted position. Reinstall the rectifier and windings. Insert the the front case half with the rotor, commutator and rear bearing (pulley does not have to be removed). Bolt case halves together. Remove paper clip. Install alternator. Enjoy the amps.

Scott

<small>[ March 17, 2002, 10:48 AM: Message edited by: sdpatt ]</small>

 

[Shoman594]

Ya on the motor mount thing i allways thought that, if the front one has failed then the rear one will follow suit because it does not have the support from the front mount.

Ill deff try the rebuild if my alt goes out on my '94 but so far i have had good luck 8 years and still going (knock on wood) wink you know what happens when some one braggs about how good there SHO is doing hehe

<small>[ March 16, 2002, 11:03 PM: Message edited by: Shoman594 ]</small>

 

[shotx]

I was thinking the exact same thing when I saw the pics.

Jeremy Hohn:
Scotty,
Nice work. I see those ever familiar blue gloves are still at work...

 

[sdpatt]

It sures saves not having to scrub all the grease off my hands and from under my fingernails. Kendall surgical gloves. A real hand saver.

Scott