Manual with o/d: synchros required

[forest]

Hello all

I have a 1967 3 liter Mark 111, manual with o/d. My mechanic - who is not a Rover specialist- just advised me of the following problems.

The synchro on the 1st and 2nd ( Part# 522373) is presumably bad. Actually he has to put it in 3rd gear first and then switch to 1st if he wants to move forward. Or start the engine with the 1st already engaged.

The 3rd and 4th one (part # 513521) is still good.

But it jumps out of gear in reverse.The reverse gear assembly part # is 56936.
Now my mechanic recently took down the engine and transmission to change the engine; he did not open the gearbox, but replaced the gearbox oil with what he told me was the grade recommended in the workshop manual. When I last drove the car last year, I remember having had some difficulty engaging the 1st gear some times, but not always. And then I would use the old trick of engaging the second or third first, etc. I do not remember the reverse jumping out.
I looked into Wadhams' catalog, but it does not appear that the synchros are available.

Does any of you know if the at least some of parts are interchangeable with the P4 or Land Rover unit or any other? The reverse gear assembly appears to be an old number.
Do you know if using a different gearbox oil, like synthetic Red Line, would help?
I have a technical inspection appointment this week and it now appears that I might fail. My mechanic just told me of the severity of the problem today. It maybe that adjustment might help, but I doubt it.
An obvious cure would be to change the entire gearbox if one in good condition can be found but I am located in Canada. Shipping from the UK would be expensive.
Can somebody help with tips?
Greetings to all
R. Forest

[Phil Nottingham]

Bad luck - these gearboxes were designed for the mid thirties Rovers and were up to their limit in the 3 litres. Internally they are are similar than P4's of the same time. However whether they were identiacl I do not know as I have no P4 parts manual. Only way I see is find another box or a p4 one to see if there are interchangeable parts. The box itself is not interchangeable as the casing differs for the rear mounts

Wadhams does not list everything he sells - gearboxes can be reconditioned in the UK though.

There is no syncro on first and its normal to start off in 2nd anyway. Worn layshaft bearings and selectors causer jumping out of gear and clutch spin/drag prevents clean selection.

Sorry cannot be of much help

[Warwick (Ozcoupe)]

This sounds strange to me. First I should add that I have no experience with Rover car manual gearboxes, but naturally I've driven many other manual cars.

Since 1st doesn't have synchro, the only things that I can see that should stop it engaging cleanly when stationary is a selector problem, or a shaft that stops spinning quickly (for whatever reason) once the clutch is thrown. If all the gears in the box are stationary, then there is probably a 50/50 chance that teeth will not mesh when slid together.

This was not uncommon (but not 50/50) on non-synchro 1st cars I have owned and most people have experienced it at some time when selecting reverse. Reverse of course never has synchro.

The problem is also often experienced when attempting to put a car into reverse for parking purposes after the car is stationary and the engine has been turned off. Could it be that you experience the problem when the car is not moving and the clutch has been disengaged for more than just a brief period? If so, try "blipping" the clutch pedal out and down again while in neutral, immediately before trying 1st.

Don't blip the throttle when you do this or you may crunch the gears. Just let the idling engine spin the shaft again.

Another possibility is that the box has been worked on before and it has early Land-Rover parts inside. Some had no synchro on 1st or 2nd. (Others will now if this is possible or not).

Warwick.

[dorsetflyer]

I doubt whether you get parts for your gearbox just by quoting those part numbers nowadays.
To be honest you really have two avenues to explore, one is to find a gearbox specialist local to you. They should be able to re-build without any problems, or two, see if there is anyone who has a scrap P5 going with a manual gearbox.
You might be lucky as one or two contributers to the site are from south of you in the USA. They might see this thread and get in touch with you.

Engaging 1st gear on most old classics was sometimes difficult as none of them had synchro 1st gear or reverse. All the other gears were synchro.
The other possibility of poor gear selection could be the clutch not engaging fully and its worth checking the adjustment of this.
The gear oil that's used is Hypoy 90 or equivalent though sometimes you can only get 80/90 which will do. A mineral oil is specified and I doubt that a synthetic oil would be advisable or any better.
Not knowing what a 'Redline' oil is I cannot comment on that, but if its Auto box fluid or some sort of engine oil then the answer is don't use it. Gearbox oil is an extreme pressure type of oil.

[Phil Nottingham]

BTW - these gearboxes do go and on - the synchro cones do wear first bt even then double-declutching can get round that. The layshaft bearings are next to go and these may be standard imperial stock sixes. Unless the box has been abused the gears should be OK - if one is chipped you could probably hear it.

First and reverse are straight cut which is why they are noisy.

The manual box on P5's was probably the least favourable option as even with overdrive its was not as slick as some of the new boxes coming out in the 1960s

I think it could be clutch related eg faulty master/slave cylinder seals , worn plate. It may even be the remote selector out of adjustment somehow.

I doubt many Land Rover parts will fit either - these did not become all syncro till the S3 in 1972.

As to oils 50 grade mono or EP80/90 will be Ok. It depend on the overdrive as late models had separate oil early ones shared it with the engine.

The correct one is in your handbook


Hope you can sort something - keep us informed

[forest]

Thanks to all. Your collective wisdom is much appreciated.
I have just instructed my mechanic to open up the gearbox and find out if the parts are really worn, etc. Obviously I will have to cancel my technical inspection appointment.

I will also post a message on the Rovernet list, in case anyone would have a spare P5 gearbox on hand this side of the pond. But in view of the very, very limited number of manual P5s that were sold on this continent, I have very little hope.
I'll keep you posted; we should find out soon enough if my gearbox is to be replaced. If the worse happens- which is finding a good second hand or recon gearbox - I may appeal to your collective wisdom again. Keeping a P5 on the road this side of the great divide is no easy task, I can tell you.
Again thanks to all
R. Forest
Canada