4106 starter swap; not all that bad.

[Barn Owl]

Reading about 4106 starter swaps is like listening to women swap birthing horror stories. Each one has to one up the other and scare the devil out of those who haven't done it.

This is how I did mine:

1.   I securely chocked the wheels and blocked the bus up.
2.   I unhooked the batteries.
3.   Through the top access hole from the inside I removed the back top mounting nut. (The one closest to the engine block)
4.   Crawling under the bus I sat up in the hole that is located ahead of the engine bulkhead.
5.   Through the bulkhead cutout I removed the four bolts holding the engine breather on and placed the breather aside. Be sure to stuff a rag in the hole where the breather was on the side of the block.
6.   I removed all of the wires to the solenoid and the starter.
7.   I removed the bottom nut using a 15/16 boxed wrench cut down to an 8" length. (You could use a 15/16 socket if you have a wobble adapter)
8.   I then removed the last top nut and slid the starter out onto my lap. (Be careful it is heavy, but not unmanageable)
9.   Make sure the new starter is a 12v left hand starter. Check the starter mount to ensure it is the correct one. There are at least three types and the one you will need is the most uncommon. If you have your old one rebuilt it won't be an issue, but I kept my old starter to use as a spare.
10.   If you have an automatic tranny you will need a gasket for the starter mount to bell-housing face.
11.   Installation is just reversing the above procedure.

Even though the rebuilt starter's mount looked identical to the one removed, there was enough variation in the casting that I couldn't get my wrench on the bottom mounting nut. I used a socket and managed to get enough bite to tighten it. If I had a wobble adapter I think it wouldn't be an issue. You could also grind the mount in that area (it's plenty thick) to give your wrench clearance room, if you remember to do it before you mount it.

My original starter solenoid was bad and that is the reason for the swap. I wasn't charged a core charge, so I am keeping the starter motor as a spare. I found that even some of the big starter rebuilders don't stock enough of the parts to rebuild a LH starter in one day, so having the spare will be nice. The solenoids are very common and inexpensive, so I don't feel a need to keep one of those on hand.

Conclusion: It's not as bad as people make it out to be. Unless you are physically not strong enough, this is a DIY job.

I hope this might help the owner of a future 4106 starter swap..

Laryn

[Buffalo SpaceShip]

Great post, Laryn. Glad it was easy for you. Did you check those big #4/0 wires for corrosion and clean 'em up? When I changed mine (on the 4108), I sandpapered the ring terminals real good and applied some terminal protectant. It's also a good time to check your engine/body grounds back there.

There's nothing like the satisfaction of knowing she'll actually start when you hit the button!

Cheers,
Brian

[Barn Owl]

Brian,

I wanted to give you a special thanks for all of your help. The email you sent back in January was very useful. I did check the wires and had the hose and fitting shop look at them. For the most part they all looked good. I did feel like I took it hard on the cables I had made. Two one foot 1/0 cables with battery terminals on one end, and copper lugs on the other, cost me $36. Made me glad those where the only ones I needed. Copper has gone crazy!

Laryn

[Dallas]

Just to relate the pitfalls of working on the 8V71's.......

Back when they were considered "Big Dogs," we had 4 of them in various trucks and 3 more in heavy equipment.
All of our equipment was bought used since we were a small logging company and always bought someones old problems.

If I remember right, all of the 8V71's we owned had starters that needed to be R&R'd sometime in their life with us and it seems almost every one of them had a 15/16" socket already on the inisde bolt when we went to do the job.

Lot's of mechanics would leave the socket there because there was no clearance once the bolts were tightened up. That was over 30 years ago and I still have a good supply of 15/16" sockets in my tool box.

Dallas

[Dreamscape]

Dallas, What a great idea leaving a socket there! When I did mine it was a bear to loosen then tighten up. Any other helpful hints out there?

Paul