I have a 1933 RP saloon with a 4-speed gearbox, and if I'm driving in third gear, the gearshift "falls" out of gear and into neutral. Is there an adjustment for this?

Signed,
A Yankee in Lord Austin's Court

Hi David

I'm no expert, but I have rebuilt my box a couple of times so I may be able to help?

If you take the lid off you will see the 3 selectors and shafts (remove the guide plate first). The bronze selectors run on these shafts and you will see some grooves around the circumference of the shafts which serve to locate the ball bearing in the selector itself. The ball bearings are preloaded by a small spring in a drilling in the selector. This may be your problem area? Engage 3rd and make sure that the correct selector shaft is adjusted so that you get a proper engagement of the ball bearing in the groove to provide positive location (slots for a screwdriver and locknuts are provided for this). The ball or spring could be stuck or broken thus giving poor engagement. If it is suspect you can unthread the shaft carefully making sure the bearing doesnt get lost and repair or replace as required.

This may be the problem or you may have a problem with something more tricky like the synchro hubs themselves, I would try looking at the selectors first as its a lot easier than my description makes it sound! .

Steve.
I have assumed its a later 4spd synchro type?

David,
Steve's probably right, a gradual fall out on the syncro box sounds like a selector fork detent spring problem. Syncro ring problems usually show as not wanting to go into gear. Steve didn't say that you can only get the rod and fork out with the gearbox out of the car, they unscrew forwards in the clutch direction. I've just rebuilt a gearbox fitting close ratio gears, there's some photos and general advice from that on the Speedex website. New springs and balls are available from the usual suppliers or from a bearing supplier if you know the sizes (they're on the website). Oh, the fork detent springs/balls are a different size to the syncro hub springs/balls. They're a close enough size to get mixed up so watch out! Oh again, if you've got the box out and in bits it's probably a good idea to look at the other two forks as well and set them all up when it goes back together.

Another thought, if it's just sliding out you can probably hold it in and put off the work for a while?!

Dave

Yes sorry I forgot to say mine was out of the car!!!!

If you do decide to strip the box and take apart the synchro hubs, do it with the hub and your hands inside a plastic bag! The springs and balls will fly everywere! Trust me I had it happen to me! .

As Dave says maybe you can hold it in until such time as you are planning some major engine/gearbox work?

I can already envisage a wonderfully Heath Robinson device to hold the lever in place that would upset the purists!!! .

Steve

David
Steve is probably correct with the springs BUT...
I had this going on and it was the leather boot on the lever. The new boot was causing so tension which pushed it back out of third.

Pat

Having already successfully patented and marketed the "Reckless Rat easy to read lignum petrol gauge" I would like to pass on my experiences to other RP users regarding the problem outlined by David in the opening post.

My little dear is a 33 RP with the four speed "twin-top" non-synchro box and it exhibits from time to time a similar problem of jumping out of 3rd gear, usually when pulling hard uphill. I'm sure the root of the problem lies in a weak, worn or broken detent ball & spring, but I've found that if you drive with the palm of your left hand on the gear lever ball (when in 3rd gear) you can grasp the windscreen opening catch with the first and second fingers to prevent a sudden 'disengagement'... I've been using this system for about the past ten years in the hope that the gearbox will eventually get better - it never has, but at least it's never got any worse!

I just need now to have a good look on Ebay to see whether they've got any of those 'round too-its' left in stock.

Thanks, gents. Given the need to remove the gearbox from the car, I will continue with my very high society method of hooking the gear knob with my left pinkie finger to hold it in place. I will also print off all these instructions and save them for the day I brave the job!

This is a great forum.

David

My car and I have come to a similar agreement.

I too had problems with "falling" out of third gear. This usually happened when decelerating, and was a gentle process, so "falling" describes it more accurately than "jumping". Since third gear is an indispensible part of the A7 braking system, I decided to fix it. New detent balls and springs resulted in a complete cure. Now the co-driver can concentrate on map reading instead of holding the gear lever !