I’ve been driving my XK140 MC OTS a lot since getting it back from the engine rebuild. It’s running great and is a pleasure, with one exception. I have no problems shifting the Moss box once moving, but from a dead stop it takes about 7 seconds for the main shaft to settle down enough to go from Neutral into 1st without a grind. I know 7 seconds doesn’t seem like a lot, but when you’re stopped at a crowded intersection and the light turns green the people behind seem to disagree. I can put it right in 1st with an uncomfortable grind, but it seems to be a bad idea, especially as I’m driving the car a lot. I’ve adjusted the clutch and lowered the idle to about 800 rpm which helped a lot, but not completely. Is this just the nature of the beast? Are there any tricks? Clutch in while in neutral? N - 2nd - 1st?
It’s easy, just utilize the second gear synchro hub to stop the gearbox. You don’t have to engage that gear. Just tug it back far enough into the gate for the cone and hub to make contact and the input shaft instantly comes to a full stop. Then shove forward into first.
If it lines up badly (which can occasionally happen since it’s a straight cut gear), then let up the clutch a hair while applying a bit of forward pressure on the stick and it will slip into gear. Use the same strategy when going into reverse because there is no synchro there either. The little first/reverse teeth on the end of the cluster gear are often seriously damaged because people try to cram it into gear before the box has stopped.
My first car was a MK1 with a Moss box, and then a MK2 through college and beyond. That technique of indexing into the 2nd gear gate and then straight forward into first became so ingrained in me that I sometimes do it in my Honda without thinking.
That is correct. It is a stubborn box, and after too many crunches, I learned to go into 2nd gear and then move up into first. Other trick is to learn to double clutch going down into worn out second gear synchros.
Yes it helps even on a car with synchro on 1st because sometimes they baulk at going into 1st.
Yep, I’ve been driving Moss boxes since 1968 and the habit of touching 2nd before going into 1st is deeply ingrained in me as well.
I’ll triple ditto that: It’s muscle memory, and quite unconsciously, I do it on any manual gearbox drive.
Us old dogs can teach the youngsters new tricks.
as many said touch 2nd…but also…800rpm idle is a bit high. The owner’s manual hints at 500 rpm…but everything must be perfect to not stumble at 500…Idle rpm of 600-700 seems to be the usual. (some say they have achieved 300-400) What say y’all on your idle rpm?. (On many distributors the mechanical advance starts in at 300-400.) Nick
…but isn’t that distributor degrees, rather than crankshaft degrees, which would translate to 600-800?
Thanks for the great input guys. I’ll adopt that.
Idle is not my car’s strong point, it has a hot cam and 2" SU’s. 800 seems the lower limit.
Hmm…have to look that up.which rpm is used in reference to mechanical (centrifugal) advance, (.thinking you mean distributor rpm not degrees) …vs engine rpm: someone out there have the answer?
Agreed. That’s what I meant to say.
The N-2-1 technique works perfectly from a dead stop! Not a scrunch at all. I feel kind of silly, but what an easy fix. Thanks so much
I don’t feel silly! It’s just another one of the mysteries of Jaguar ownership and driving.
You will know you truly have arrived when you can downshift into first gear by double clutching…
An 80 year old friend still owns an Austin Cooper S, which he purchased new in 1967. That was the final year of the 3-synchro, four speed gearbox in the Mini. During the late 1960s and early 1970s both Dave and his wife won numerous autocross events using a unique second to first downshifting technique.
When needing the extra power of first gear, they would depress the clutch and simultaneously jam down the brake pedal to momentarily lock-up the front tires. At that same moment they would downshift into first gear. This would allow the same no-grind down shift from second to first as if the car had come to a full stop,
When expertly timed, this technique apparently caused no excessive wear to the gearbox. Dave’s Cooper S still has its original 3-synchro gearbox, which has never been rebuilt.
As a high school senior I was taught the double clutching into first trick by a fellow high schooler Bobby Rahal in another high schooler’s Austin Healey 100-6.
This is a valuable technique to learn. It enables you to go into first at any practical speed. Useful if you are rolling to a stop and suddenly the light turns green.
I’ve done multiple mountain drives which are ideally taken 1st gear to get thru really steep and tight hairpins (like the 2 hairpin turns at Smuggler’s Notch in northern VT). Ditto the road up Mount Equinox in southern VT.
I’ve spoken on here about the 1923 Kelly Springfield fire truck that I rebuilt in the late 70s: it had a three-speed, sliding gear, absolutely-no-synchronization whatsoever transmission!
Before I handed it back to the customer I did my usual customary 200 miles on the engine and transmission and let me tell you I got really, really good at double-up and double-down clutching: Tweety was an invaluable training aid!
As in Bobby Rahal Indycar owner/ former driver? A pretty good person to learn from…