S1.5 Cant select REVERSE gear

My recently fully restored 1967 E-Type S1.5 with a “Jaguar” full synchro Gearbox seems to be fine in all gears, but linkages can’t find the slot for Reverse Gear at all when the engine is hot, but when cold it slips into the reverse gear slot easily. I guess the answers lie with the selector linkages under the gearbox console cover. Any experiences or thoughts please…
Thanks
Ross

When you say that the linkage can’t find the slot for reverse gear, are you referring to the movement of the top of the gear lever to the left, or its movement to the rear after moving it to the left.

Reverse gear is selected within the gearbox by sliding the Reverse Idler Gear to the rear to engage with Reverse Gear. It’s moved to the rear via a lever with a yoke at one end that is always in assembly with the gear and its other end with the Reverse Selector Rod.

If you’re referring to not being able to move the top of the Gear Lever far enough to the left, to be able to then move it to the rear, there is an Indent Ball, Spring, Setscrew and Lock Nut assembly at the rear of the Reverse Selector Rod, that if adjusted too tight, makes moving the top of the gear lever to the left difficult. This assembly is there to help prevent the inadvertent attempt to select Reverse Gear. There may be a possibility that heat could affect the adjustment of this assembly through expansion and may be the cause of your issue.

The adjusting Setscrew and Lock Nut are accessible by removing the centre console and the Transmission Top Cover; the adjustment instructions are in the E Type Maintenance Manual. The procedure is the same for all E Types and other models, equipped with the 4 speed all synchromesh gear box.

If the adjustment of the Indent Ball doesn’t fix your problem, the Top Cover of the gearbox can also be removed with the centre console and Transmission Top Cover removed. Once removed, the Reverse Selector Rod mechanism can be inspected for possible problems. To remove and replace the Top Cover, the gearbox should be in neutral. When replacing the Top Cover, the top of the Reverse Lever in the gearbox should be towards the rear. When replacing the Gearbox Top Cover, care needs to be taken to ensure the Reverse Selector Rod in the Top Cover, engages correctly with the top of the Reverse Gear Lever in the gearbox; a small mirror can be handy to see this is happening when working in the confines of the Transmission Tunnel.

Brent

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Hi Ross…if your just haveing a problem engageing reverse when hot then this is not an uncommon problem…usually due to incorrectly adjusted clutch slave cylinder pushrod or air in the hydraulic fluid…reverse does not have syncro so more easily affected by the abovd…Brent has given a detailed explenation of the lever mechanism…i would check fluid and pushrod first…Steve

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Here is a suggestion.
When the engine is warm and you cannot select reverse, turn off the engine and then try.
If you succeed, it is possible the problem is clutch disengagement. If you do not succeed, the problem lies elsewhere
Dennis
69 OTS

I will be interested to see what Ross says. It sure seems to me if it was the clutch dragging or not disengaging one might think the symptom would be gears clashing, not reverse can’t find the slot. But we all describe things differently.
Tom

Hi Tom,
For sure, that would be the case. The Reverse Idler Gear would be rotating when trying to engage with a stationary Reverse Gear and irrespective of how ever so slightly that may be, they would gnash.

@xk140fhcross
Hi Ross,
What can also give you the impression of “can’t find the slot”, is that by chance, when the First Motion Shaft and Lay Gear cluster, which drives the Reverse Idler Gear, comes to rest when the clutch is disengaged, the male tooth form of the Reverse Idler Gear is aligned with the male tooth form of the Reverse Gear. The face ends of the gear tooth form of both gears are chamfered, which allows for some misalignment of the Male and Female profile of the two gears. But if there is enough overlap between the Male Tooth Profile between the two gears, no amount of force will have the two gears come into mesh.

If there is no gnashing of teeth when trying to select Reverse, this would just about rule out the clutch dragging. If this is the case and the gear lever seems to be in the correct left position to select Reverse, try:

  1. putting the gear lever back to the neutral position
  2. releasing the clutch for a short period, so that the Lay Cluster and hence the Reverse Idler Gear will spin.
  3. depress the clutch so that the Lay Cluster and Reverse Idler gear stops again.

In doing the above, the hope is that the Reverse Idler Gear stops in a position, relative to Reverse Gear, so that the Male profile of one gear aligns with the Female profile of the other and therefore, allows the two gears to engage.

More often than not, the gears will stop in an alignment close enough that allows the lead in chamfers of each gear to do their part in having the two gears engage, but having the Male Tooth profile of each gear align well enough to stop the gears engaging happens often enough when the gearbox has no synchro on reverse. This condition happens only by chance and because of the lead in chamfer of each gear, it happens far less frequently than the gears engaging without issue. However, the temperature of the gearbox shouldn’t have any bearing on it, as its a chance happening.

Brent

When i had a problem with the reverse linkage, not related to temp though. It was the detent ball was missing. The spring was mashed and jamming in the detent slot. After the ball and spring were replaced, i found the tension adjustment to be more sensitive than you would think.I ended up with very little spring pressure.

My experience the same with reverse, the ball and spring is quite sensitive to adjustment and fiddling was needed to find the sweet spot

When I first drove my series 1.5 I found to my distress that I couldn’t shift into reverse (couldn’t move the gear lever to the left by pushing). I learned from the previous owner that at least on my car, I need to give the lever a sharp slap to the left to overcome the resistance before moving backward into reverse. With this technique it has always worked since.

David

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Hi David,

I always thought it was designed to operate this way, no?

That’s the way all my all-synchro boxes have always worked, S1 4.2 2+2, S3 5.3 OTS and Ser. 2 XJ6C. YMMV.

Cheers!

My '68 has also always liked a firm slap to the left to get it into reverse. I too always thought this is normal in my 22 years of driving it.

David
68 E-type

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On humous note, last fall I couldn’t get my '68 into reverse, well after driving my '64 with the Moss box I was trying to push it the wrong way…
Joe Schmedly (with apologies to Lloyd)

A couple of years ago I was test driving a 2006 Mitsubishi Eclipse w/6 speed manual that my son wanted for his first car. The wife and son were with me for the test drive. At some point I needed reverse to back out of a parking spot and couldn’t find it to save my life. I had to put the car in neutral and push it back. Turns out there was a collar on the neck of the shifter that needed to be pulled up to engage reverse. I had never seen that before!!

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My 65 Corvette has a similar collar on the shifter column just below the knob that needs to be lifted to shift into reverse.

David

This same thing stymied me in a dark French parking garage and it was a rental car. I needed to back it out to get going. It took a while to finally find it.

S1.5 gearbox is stuck in reverse gear!

I am helping a friend restore his 1967 E-type HTC S1.5 with the manual gearbox. After the engine and gearbox were reinstalled, the gearbox will no longer shift out of reverse. Prior to going back into the car, the shift lever would move to neutral and other gear positions. The only work on the gearbox was an oil change.

Can the gearbox gear selection assembly be adjusted to free the reverse, or the top cover removed (while stuck in reverse) to manually move the gears to the neutral position?

Since the engine is not yet ready to start, rotation of the input shaft is by hand-cranking the engine.

I thought that the solution might be similar to the “won’t go into reverse” problem.

Thank you for any help.

Jim

Check to see if the gear leaver might be binding on the tunnel. Engine level, not leaning to one side.
pauls

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Remove to top cover. If the gears can be moved, the problem is with the selector detents in the cover, if not it’s going to be a strip down to find the problem inside the box.

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Thank you

The tunnel is off and shift lever clear. However, the car’s front end is up on jacks so engine not level. I’ll let the front end down and try again. Not optimistic!

Jim

I understand. Thank You