Overdrive

[Richardtr3a]

I took my TR3A out yesterday for a local run, to warm up the engine before antifreeze replacement. The engine started well after 2 weeks of rest and it was all going well until I tried the overdrive. It did not connect.  This was disappointing. The gearbox and the overdrive have been overhauled by well know specialists  and only a few thousand miles use in the last few years.

I tried again this morning in case it was the cold weather. It was the same. When I got home, I  tried it in the garden with the engine not running and there is a loud click below the Relay. So it looks as if the solenoid is working. I need some advice on what to do next without removing the gearbox tunnel. Is there any special short cut to find the problem and repair it. It looks to be impossible to remove the cover plate on the solenoid housing without having full access.

Please help.

Richard & B

[Lebro]

Oil level correct ? if so the next possibility is the adjustment of the operating arm is not quite right .

Bob

[RogerH]

+1 above.

Hi Richard,

 have you got access to the little jigging arm on the right hand side of the OD  - your tunnel may have a blanking plate over it.

When you select OD does this arm move to the engage position?

 

Roger

[iain]

Hi Richard 

if the solenoid activates, it could be out of adjustment…..unlikely if it was working recently. But check as Roger suggests.
It could be oil level? Evidence of leaks? 
Could be a small piece of **** under the actuating valve ball…..needs reseating to rectify. Again on the handbrake side, remove the plug pull the actuating valve out  use a magnet to remove the ball, clean, replace reseat and reassemble as per the WSM.

Iain

Edited December 9, 2023 by iain
Didn’t read the description for the problem properly…..doh

[john minchin]

I had my A type overdrive stop working. A plunger (which may be the pump) which is revealed by taking the large brass nut off the bottom had stuck. It came free with a nudge and has never given trouble again.

I took the opportunity to slightly 'over adjust' the solenoid function by clamping the lever to slightly too keenly engage the OD, this is discussed elsewhere on the Forum. It comes in nice and sharp now.

John

[Richardtr3a]

It is looking like tomorrow morning in the garage. I plan to check the oil level and top up if necessary. I have just checked the storage shelves and at the moment I have two half used cans of Dynalite 40 gear oil . Would this be OK for the gearbox ? What would be the best oil if I plan to drain the whole gearbox and refill.

 Hoping for a no rain day ??

Thanks Richard & B 

 

 

 

 

[RogerH]

Hi Richard,

your Dynalite 40 oil is OK.  Although it gives no GL number it is GL4.

I run Penrite GB40 and that works very well.

 

Roger

[Richardtr3a]

The weather is Sussex is fine and with no rain I managed to pull the carpet out of the 3A and have a check on the oil level in the gearbox. The dipstick does not line up well  with the access hole in the tunnel. However once it was out it looked as if  there was no oil on the end at all.   I cleaned it up using kitchen paper and tried again. It did not look as if  there was any level near the lines on the dipstick. I tried a third time and tried the dipstick cleaning along my left hand and there was no oil.

So I still have the tool to get oil in the gearbox. How should I measure the amount required to get a reading on the dipstick in a correct place.??

I am leaving now  , 13.30 , to walk my dog in the sun across the local fields.

Please let me know Richard & B

[Lebro]

2 choices,- 

Drain out all the oil which is left (two drain plugs, 1 on gearbox, & one under overdrive) then refill with the amount shown in the manual (2 litres)

or, add some oil, then keep checking with the dipstick till it's on the mark.

Bob

[Charlie D]

15 hours ago, Lebro said:

...keep checking with the dipstick till it's on the mark....

Pour the oil down the dipstick hole (With a funnel and a tube if it is a bit out of line with the gearbox cover.) No need to  crawl under the car and undo plugs.

Charlie.

[Lebro]

Yes, but Richards point was how much to put in.  If the gearbox has the removable plug on the side then fill till oil comes out of the hole, but if the box has a dipstick then I don't think that hole is present. (pre TS50000)  item 71  below:

https://www.moss-europe.co.uk/shop-by-model/triumph/tr2-4a/clutch-transmission-drivetrain/gearboxes-components/external-gearbox-tr2-4a-1953-67.html

Bob

[Richardtr3a]

Thanks Bob,

I remember that I had a purpose made spanner to allow removal of the plug. But it will take a long time to find it in the garage and then I have to lie in a muddy puddle to use it. So I tempted to try topping up with small amounts of Gear Oil. If I go over the top mark on the dipstick would it give me problems with the clutch etc.

I am keen to fix the problem but the weather is bad today.

Thanks Richard & B

[Charlie D]

Richard,

If you go over the top mark on the dipstick you can remove excess by sucking it out with a tube through the dipstick hole. If you use a long enough tube you can even do it by mouth. (A short tube may not give you time to stop sucking...)

Even an old bicycle pump could be pressed into action to suck it out . Yes, I know the bycicle pump is designed to push stuff out rather than suck stuff in, but it will work.

And you won't have to jay down in a puddle.

[Richardtr3a]

I have topped up the gearbox oil and left it overnight to settle down.  My portable oil pump looks like a mastic gun. As you open it the oil is sucked in and when the trigger is pumped the oil is discharged. There is a scale on the side of the clear plastic tube  which showed 200 ml of oil in the pump This morning I checked the dipstick. I tried three times and there was a very small trace on the end of the dipstick but no oil near the two level indicators. I am keen to get the oil level higher and need some advice on how much to inject into the gearbox to get a level that shows easily on the dipstick.

Any advice would be very useful.

Thanks Richard & B

[Ralph Whitaker]

I would try another 200ml and see where that gets you. Any idea where all the oil went?, if the gearbox is empty as it seems there must be evidence of a fairly large oil leak somewhere.

Ralph

[Deggers]

20 hours ago, Richardtr3a said:

I have topped up the gearbox oil and left it overnight to settle down.

No need to wait overnight, Richard. Gear oil isn't particularly viscous, it will settle in seconds rather than hours.

As Bob said, pump some in, check the dipstick, and repeat till full.

[Richardtr3a]

Thanks for the help.

This morning I added 100 ml and there is something on the dip stick but the oil is so clean that is hard to read accurately. So this afternoon I am driving the TR to the Post Office to send some Christmas cards. It is about 6 miles round trip and I will try the overdrive on the way back and read the dipstick back at home , when the oil should have some colour.

After Christmas it is RB106 replacement unless the winter weather starts properly.

Richard & B

[rcreweread]

Richard - the oil level in the gearbox/OD does not find its level naturally when first filled or topped up - the reason it goes down after initial use is because it gets pumped around the overdrive and that fills up some areas which aren’t reached by simply filling.If you empty a gearbox/OD unit by undoing the gearbox drain plug, you would be surprised how much oil still comes out of the OD unit, but you have to tip up the OD end.

if you can only just see the oil on the dipstick now and you havent yet driven/used the OD, I would be inclined to put a bit more in

cheers Rich

[Richardtr3a]

Thanks for the advice. I have put more oil in this morning and it is now on the dipstick above the low mark. I have to drive it tomorrow when there is no rain, and I need to know how far to go before the overdrive will connect. I do remember doing this last time , years ago . when I had new oil but am not sure of the approximate distance.

Please let me know

Thanks Richard & B

[John Morrison]

Richard distance shouldn’t matter 

the O/D should work soon as you are in appropriate gear and at sufficient revs

John

[RogerH]

+1

[Drewmotty]

Don’t worry about rain either; rain won’t effect it 

[Richardtr3a]

The rain keeps me in the house. 

[Lebro]

You could always jack the rear up off the ground ( & place on axle stands),

then run the engine up & test the overdrive by watching the revs verses the speedo. & all in the dry !

Bob

[rcreweread]

On 12/14/2023 at 1:11 PM, John Morrison said:

Richard distance shouldn’t matter 

the O/D should work soon as you are in appropriate gear and at sufficient revs

John

Hi - I'm sorry, but in my experience, this is not totally true - if the oil level in the gearbox and OD has fallen to the extent that the OD is "dry"and stopped operating, it can sometimes need a run of up to 20-30 mins to get it going and purge any air out of the hydraulics within the OD - once it starts operating, then it should engage/disengage almost instantly on being operated .

Cheers Rich

Edited December 15, 2023 by rcreweread