Borg Warner 66 Transmission Adjustment
To adjust the bands w/o a lift, I put the rear wheels up on some ramps and used sturdy jack stands raise the front to the same level. This gives you enough room to comfortably work underneath. The rear band is on the intake side of the car, on the side of the trans, towards the rear. As far as I know, it's only accessable from under the car. Fortunately, it's easy to get to. The front band is on the other side of the trans and is rather hard to get to from below because the shift linkage is in the way. However, there is a front-band access hatch inside the car. I removed the side cover of the console (where the radio is, next to the parking brake on US cars), pulled back the carpet and found an oval-shaped perforation in the sound proofing material. I cut along the dotted line and underneath was a little 6inchX4inch plate bolted onto the side of the trans tunnel. It's just to the rear of the gas pedel (on US cars). With the plate off, the front band is relatively easy to get to. The band adjuster consists of a "bolt" with a square end and a lock nut which keeps it in place.
Both front and rear band adjustments are made in exactly the same way.
Also, the front band can be accessed from below by first removing the nut that is holding the selector lever to the selector shaft and removing the lever.
I fixed my BW66 last night. I won't be installing a TH350 (for now, anyway).
First, thanks to Bob Reid for telling me what the manual said about my problem (slipping/no reverse in a BW66 -- car is an 84 XJ6 SIII VDP), and to Lawrence Buja (on the FAQ) for the band adjustment procedure.
I needed to adjust the rear band. The procedure calls for 60 inch-pounds, backed off 3/4 turn. The adjusting bolt has a square head. I had the proper 5/16" eight-point socket for my torque wrench, but the Jag bolt has its corners chamfered, so the socket wouldn't catch.
Great. So there I am under the car, and I can't get the torque wrench on the bolt. What to do now?
It turns out that a 5/16" open end wrench fits just fine. I'm thinking about the adjustment specs, and wonder "What if I tighten to 61 inch-pounds, and loosen 11/16 of a turn?"? Couldn't matter, right? THe adjustment spec seems to have mixed tolerances. You don't tighten to a specific torque, and then back off 3/4 turn!! Like digging a ditch to a thousandth of an inch!
So I tighten the adjusting bolt and, sure enough, there is no continuity of adjustment. It is loose, and then it cinches down at the bottom. Apparently, the reason for the 60 inch-pound specification is so you have the thing snugged down, but not cylinder-head tight.
60 inch-pounds is 5 foor-pounds, heck, I can approximate that! So I just snugged up the adjuster, backed it off 3/4 turn, and tightened the locknut. The adjuster was WAY loose, so for sure the problem was that the bands could not grab the drum.
Test drove the car, and reverse was perfect!
Even a blind hawk gets a few acorns!
Total repair time was 15 minutes to jack up the car, 5 minutes to adjust, 10 minutes to unjack, and 5 minutes to test drive. I can only imagine what I would have paid to any transmission shop if I had pulled in with a Jaguar, complaining of no reverse!
... Regarding brake band adjustment on series II cars. First make sure you put the car up on rams BEFORE slakening off the lock nut on the front band adjuster (seems this part is left out on all descriptions). You will need to not only remove the access panel in the drivers side foot well (LHD) but get underneath the car also to be able to tighten the locknut whilst holding the set screw still. I found two excellent tools for the job. One is a brake adjusting tool as sold by many brit parts houses. It has a quarter inch open ended square on one end and a tiny closed end wrench on the other for bleed screws. The other tool is even better. At your local hardware store they will usualy have a section for welding supplies. There is a "T" handled wrench that is used for opening the valve on gas cylinders, it is about six inches long with a "T" shaped handle and a square quater inch socket on the end. Cst about $3 !! it's perfect for the job!
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