Re: [DML] Broken Shift Linkage

[kayoong@xxxx]

I experienced the same problem twice. 

I drive my DeLorean daily and with the constant shifting in the NYC traffic 
this doesn't help the pivot bolt at all. 

My first experience was about 2 1/2 years ago on a Saturday morning in the 
streets of NYC. I had made a shift from 2nd to 3rd gear and the linkage bolt 
gave way. No respond with the shifting at all. The tranny is stuck on 2nd 
gear! I call Rob at PJ Grady on my cell phone and I told him of the 
situation. I drove my DeLorean to Rob that same day in second gear doing 35 
to 40 MPH @ 3,500 RPM. It took almost 3 hours to get there, a 60 miles trip 
that would have taken 1 hour and 15 mins. He change the pivot bolt in ten 
minutes -- no charge. He even given me a "extra replacement" bolt that I had 
carried in the DeLorean as a spare.

Well, guess what? Ten months and 11,000 miles later, it broke again. That 
same feeling "ugly feeling" again -- It broke in the neutral position, while 
I was trying to downshift, in the decelerating lane while exiting off the New 
York State Thruway. So, I coasted off the highway's exit and I pushed the 
DeLorean into a garage that was next to the exit. A young enthusiastic 
mechanic made it his business to work on the DeLorean which was an advantage 
to get me back on the road immediately. They put the DeLorean on the lift 
and changed the broken pivot bolt in fifteen mins for grand total of twenty 
dollars.

The pivot bolt has inherited problems. It is made of mild steel and has an 
unusual physical designed for the job it is to do. The main shaft which is 
the body which acts as the pivot post for the shift rod's linage point and 
the thinner shaft's end has threads which starts at the shoulder. The 
thinner end inserted into the chassis which held down by a washers and a lock 
nut. Since, the threads are cut onto the thinner shaft starting at the 
shoulder, this naturally weakens the bolt and being mild steel doesn't help. 
All the combined forces will stress the bolt and share off at the threads 
when mounted. It is only a matter of time.

In my case, both times the bolts "sheared off" at the same area, at the 
shoulder where the threads are. Rob had several customers had the same 
problems too. So, to avoid the problem of the shearing breakage, in the 
future, I took the broken bolt and placed on a lathe and drilled it, to 
"hollow" it out. This is to accommodated a HARDEN bolt which will act as the 
"new" thinner section and CAN take the sharing stress. A simple project -- 
cheap, fast and effective without manufacturing a new unit and have it 
hardened. This modified unit is on my DeLorean and it has been nine months 
and 10, 000 miles -- so far so good. 

While you are at it, I suggest that you should check the gear shifter's rod 
lever pivot. The point where the rod is drilled and the "reverse" pin is 
inserted through. This right under the leather boot and the larger rubber 
seal under the center console. This is another weak point with the DeLorean 
and it too had broken on me. You can still carefully shift into gears -- but 
no reverse. Rob told me, "This situation can occur as one within several 
hundred cars." I understand there is nothing you can do to avoid this 
breakage. Maybe when shifting, do it softer or lighter? I think it is a 
poor design and I was the lucky recipient again! It is an assembly item that 
is very EXPENSE to replace -- not like the pivot bolt. 

Kayo Ong
#05508
Lic 9D NY