Sunday, May 26, 2013

Smooth shifting on a 30+ year old car.

Smooth shifting on a 30+ year old car.

I once drove a very low mile hardly driven DeLorean, and I was a bit surprised how it shifted as compared to mine. When I shifted on 2109 for as long as I've had it, it always seemed to mechanically clunk at the linkages and seemed very loose compared to that other DeLorean that I was driving.  I made a mental note to look into that one day.

Fast forward a several years and fellow DeLorean owner Mike (aka: Mike the Lotus Guy, Mike the parrot owner guy, Mike the zany IT guy) last week posts that he just changed the bushings on his DeLorean, and how great it shifts now ("My Elise wishes it shifted so well").  That triggered that mental note I made some time ago, and made me look into this further. Looking at the parts it seemed straight forward enough, and I contacted Mike with a question on access. His response went above and beyond in that he offered me a seven step how-to/tips of how to change the bushings. Very cool, Mike.

So I ordered the parts and waited until the weekend to start it. I completed the job in about half a day (I don't work fast, so factor that), and the results are indeed very rewarding, the car now shift much smoother, much tighter, you can really feel the bushings in the linkages contributing to all this as you shift.  Another good thing about this small project, is that it is a very inexpensive job in terms of parts, and very straight forward for you do-it-yourself types.  

(Sorry, not a lot of pictures here as I usually do, and of the few that I took most were not terribly usable - but again the results here more of an improved feel and performance which is difficult to capture in pics or video.)

Parts Required:
100775: Bushing, Rubber  (Total 4 required) - #8 on diagram below
100776: Bushing, Sleeve  (Total 8 required) - #7 on diagram below
SP10025: 4 M8 x 1.25 nylock nuts, (Optional, to replace the originals.) - #6 on diagram below
At the time of this writing, less than $40 in parts. Interestingly both the sleeves and rubber bushings are listed as "DMC Improved Parts".  The rubber bushings that came out of my car were different, inferior I would even say, that to these new ones.  The sleeves were the same, and as I have a very complete list of work history on 2109, and don't see these ever changed, I may have had original parts. 

Reference above at:  DMCH Web Site


The list that Mike sent me is below (used with his permission), I added my notes as to my experience and a minor optional deviation, prefaced below under "Ozzie:"

So here goes:

Ozzie: Obviously, lift the car for access to bottom. As always use proper safe methods. If you use stands only, at least shove some tires underneath just in case and try not to bump into them as you wiggle your way under car (think of the game "Operation" here).

1. Change the bushing on the shift rod at the transmission. Easiest one. 17 mm wrench on the bolt side, 13 mm wrench on the nut side. Use ratchets; the bolt is long.
Ozzie: I concur, this was a cinch.  My only other recommendation is to ensure that you replace the rod in the same way it came out, so you don't change the working linkage adjustments of your system.

2. Working in the accumulator port, change the two bushings in there. Just a 13 mm ratchet needed here, as the shift rod ends sit on studs in there. Go ahead and tighten up the nut for the rod that goes back to the transmission after changing the bushing.
Ozzie: Ah the accumulator port (access hole), I have mental scars from an accumulator replacement many years back in my garage: car inches above your chest, limited arm leverage to works, fun.  But this was different, the clevis, or "Bellcrank Assembly", where the two link rods rotate from is not entirely visible from below the car, but easily enough accessible by hand and to work it with a ratchet wrench.  As for replacing the bushings at this point, I concur as he wrote. Once you figure out the best way to wrench it, it is very straight forward.  

3. Only barely thread the nut on to the stud that the shift rod going to the shifter assembly sits on. This will allow much greater movement in the next step.
Ozzie: This is where I deviate a little from Mike's suggestion. What he wrote works, but I found it easier to just remove the shifter rod, remove old bushings and leave it disconnected. You'll see why below.

4. In the car, remove the shift knob, undo the two screws holding the shifter cover down. Remove the shifter cover and the shift boot.
Ozzie: Yup to above. And when I looked at what was under there... well, I'm getting ahead.

5. Use a 15 mm socket to remove the bolt for the pivot fork on the shifter assembly. Turn it sideways and you'll be able to pop out the clevis pin for the left/right shift cable.
Ozzie: Yup to above, work slowly here and try not to drop the small parts (clevis, pin, washer) down in to the frame.

6. Remove the four nuts holding the shifter assembly in place. 10 mm.
Ozzie: Yup to above, again.

7. Lift the shifter up, and wiggle it past the hard lines, etc. That will get the shift rod up high enough to undo the bolt & nut to change the bushing.
Ozzie: Mike's notes end there, and you can see why, which is fine. However, this is where I changed it up a little.  What I found under the shifter boot, which I've seen before and knew that someday I would address it, was a lot of dirt and filth attached to the grease on the shifter and nearby areas, like a very dirty visible part of the frame.  So for me, the entire shifter had to come out for a clean up of it, and the area it mounts in. Since I left the linkage loose at the clevis, I pulled the shifter up and completely out, without a problem.

Now with the shifter out, i was able to a) very easily replace the bushing and sleeves, and b) clean off the assembly and apply some lithium grease to the moving parts.

Now all that remains is an added step, since I removed the shifter assembly:

Step 8.
i) Put shifter assembly back in place, guiding its linkage rod back from where it came from.
ii) Reconnect the clevis pin hook up, and then check for shifter for functionality.
iii) Go back under the car and "fish out" the shifter rod by feel, now use the new sleeves and bushing and tighten it up on the clevis pin.
iv) Check a) your work to ensure all it tight under the car, and b) the shifter is traveling to the shift points as required, and if so, then lower the car, and button up the shifter assembly and for a ride.

What I found.
In general, the rubber bushings that DMC now sells are certainly better than what came out of my car. The new rubber bushings have 90 degree flare edge on both ends, the ones that came out of my care only had it on one side.

Except at the transmission side, all the other bushings sleeves that came out of my car were in very good shape. The sleeves on the tranny side, since it is the most exposed to the elements was pretty beat up.

Rubber bushings:
The bellcrank ones were not too bad really. However the tranny side rubber bushing tore itself part upon removal because it was pretty well aged (again, the one most exposed to the outside).  The big surprise was the shifter's rubber bushing, it was pretty worn and obviously contributed to a lot of sloppy side to side play that I had been driving with. (BTW: Mike also confirms similar findings on his car.) No doubt this was the link that was the sloppiest and mainly caused the mechanical clunking sounds. While the other three get just rotate in place, this one rotates at different angles because of the shift points, so it gets the roughest treatment.  
Picture shows old bushing and sleeves from the shifter rod end as they came out, and the new set installed.

Thanks to Mike for posting this quick fix, and for reminding and motivating me to get it done.  This is truly a big bang for the buck job, in the upkeep of these cars.

As always, if you have a few minutes, be sure to check out the "Best of" postings