1966 pedal box spring renewal (late box?)

I am posting this as a new topic to clear away the confusion on which box is it and whether or not to bother replacing the return springs. The car is a 1966 4.2 2+2. the pedal box has both pedals inside. Looks like the shaft is pressed in from one side but there is a lock nut and shaft adjuster(?) on the other side of the aluminum box. My clutch return spring is broken, should like to replace them both. in older threads some are calling this the late 4.2 box, but I have not been able to find anything in the archives or in all Jaguar books I have on hand about removing the shaft. Might be necessary to heat the casting? May just tap right out. I hope someone has done this job and can help out please.

I just did this, well worth it. My clutch pedal spring was broke. The old brake pedal spring was weak compared to the new one when it was installed.

does the pedal shaft just drive out then, unheated?

Don’t put heat on this. It’s not pressed in and is unlikely to be corroded. It should be a slip fit. I am not familiar with your box as I have a 3.8 box. On mine, the same shaft services both the clutch and brake pedal and the brake pedal has a set screw clamping the pedal to the shaft. Is it possible that yours is like this? The bolt on mine is released from inside the box and it is a nightmare to loosen inside the car. It can only be done with an 80 degree offset spanner.

On mine I think there is also a circlip and fitting that need to be removed before it slips out easily. Also worst of all, there is not enough room to actually slip the shaft out. It collides with the steering shaft box. I’d carefully eyeball and measure to make sure it’s even going to work before getting started.

Sure wish I could learn how to post a photo! My box is out on the bench but not the same as the 3.8 box. there seems to be 2 before mine. my box still had a tag on it July 66 which coincides with the rest of the car… is that considered late 4.2?


Heres a photo,wife support! Also showing 4.2 driveshaft that was in an earlier post of mine

When you undo the big bolt, the shaft will slide out without heat or fuss. At one time, there were malformed replacement springs being sold. I think these have long since been flushed from the market, but if you find the spring seems too small to fit, it’s probably not you.

So both pedals are serviced by one shaft. The brake pedal is probably splined. I would be surprised if there wasn’t a pinch bolt up at the splined knuckle to firm it up. Otherwise it would have to be extremely tight on the splines. Flip the pedal both ways and use a mirror if necessary.

without looking it over it seems to me the pedals both just rotate on the shaft freely, no need for splines the shaft does not turn, am I missing something here? My PC is a long walk from the shop…
will look later

Steven, as you surmised, they simply rotate on the shaft. No splines on the pedal. Can’t recall as to whether the shaft throat was splined, but it is easy to get it out once on the bench. Not sure whether it can be insitu

Okay, so that must have changed between 3.8 and 4.2 boxes. Not sure why they did that or what could be preventing removal.

Thank you Erica , Im so glad I have the newer box which as you have pointed out must be much simpler than the earlier versions , progress I guess. I appreciate all the comments as I continue to learn more about the car. Have owned it too many years in its current disassembled state, not all by yours truly. I am in need of photos of the firewall/ bulkhead showing clutch and brake lines connected to masters / boosters and reservoirs. Will be asking about that soon. My current effort is bolting up the drivetrain again , trying to make certain I am doing all that i should beforehand… be nice to have clutch and brakes😊. Most of that done with engine in place I hope.

Thank you Erica for your knowledgeable post. Im so glad I have the improved style pedals , booster/ brake system. At least I expect it was an improvement :blush:.Jag Lovers has been my go to place for many years now but just getting round to reassembly. Many questions still. I really value the photos folks post, so very helpful and at times essential for proper understanding. Looking forward to finally having a good go at my car after too many years sitting apart.

And there was an early 4.2 pedal box (such as fitted to my 1965 car) which was essentially the 3.8 box without the mounts for the bellows.

Thought i should update on pedal box spring renewal. Finally disassembled it yesterday, replaced the broken clutch spring with a new one that was of disappointing quality. Same thickness of steel but seemed very weak and poor fit. I mistakenly bought two clutch springs thinking brake was the same, its not🥴when i get the brake spring i will try the extra clutch spring to see if its any better. The tabs which hold it back for tension are too wide and looks like one could slip off to the side putting all the tension on one . Thats how i found it , one side broken. Looking it over the old one broke in another place.i would sure hate to do this again, cannot be done in place IMO. The nylock nut was very tight, i had to clamp the box in my big vise and use a 12" bar with a tap of the hammer to break it loose. As always proceed with caution so nothing breaks! Long story short, not a fun job and todays new parts are not that good.

Steve - I share your frustration… Did the same thing last year and the spring looks like it does not engage to the stops as well (1966 FHC). I recall in some older threads where folks mounted an additional spring from the pedal to the underside of the dash - I would have to dig thru the old threads - others may post to here as well.
Thanks,
Nick

Mine has weird uneven ledges inside the housing that I think are causing one side to carry uneven tension. I’m not sure why it would care but after 4 breaks I’m fed up changing it. I might try grinding, or building up the low side to try and even it out if I ever do it again.