901 gearbox failure - Need a new one if anyone can help ?

[amallagh]

My 901 gearbox failed catastrophically this wknd turning it to virtual scrap. Shattered gears, bearings, fork and probably damaged the case. When I know more about what happended I'll put details on here as the bits are disected, but suspect not a lot will be salvageable.

I'm looking for a replacement 901 box if anyone can please help ?

I'm supposed to be doing a trip to Scotland in 2 weeks but that is looking prety unlikely unless I can find a replacement asap.

Thanks
Andrew

[rhd racer]

Hi Andrew

There is a 914 side shifter on e-bay in Kent for £400. If you had all the internals I would buy the case, nosecone and all the side shift components to convert from a tail shifter from you for say £75, to help keep your costs down?

Give us a bell if you are interested - alas not in a position to get down there in the next couple of weeks though. Just an idea to help you out.

Cheers
Wayne

[amallagh]

Hi Wayne,
is this really as easy as just swapping the internals from a 914 box to a 901 case ?
Even if there was just a few key components short then I could still end up with a non functional gearbox. Hope someone on here with more knowledge than me can offer some direct advice/experience about doing this in practise and what if any components are different. With everything at least running the other way round then I would have thought some things were different.
Regards
Andrew

[Bruce M]

The same seller has a tail shift for £250 so that would make better sense (if condition is similar).

The gears in the 914 are different (higher ratios & not hardened to the same quality) but usable as a quick solution.

The nosecone & shifter arm needs swaped, diff flipped and the breather moved (hole needs drilled in case).

[MBEngineering]

HI Andrew
is your 901 box Ally or Mag case??? as most of the internals will fit from the Ally to the 901 Mag case and the later 911 Mag case box fitted to the 914 and 2.2lt cars, any part replaced on the pinion shaft will need the pinion position re-setting and the diff back lash,

The 914 gearbox only has the diff in the other side of the pinion to make it run the other way round and not the engine running backwards to get the 914 to move forwards

If your 901 box is the Ally one, it looks like you have taken the end off the input shaft for 1st gear and as the box had 2nd and 4th still working, the rest of the box could be still in working order, just the shafts have moved in the box and stopped the selection of the 3rd and 5th gears, has the case any damage to the out side?? if not it could be still usable, will need some photos or to inspect the box for damage report.

regards mike

[rhd racer]

HI Andrew
is your 901 box Ally or Mag case??? as most of the internals will fit from the Ally to the 901 Mag case and the later 911 Mag case box fitted to the 914 and 2.2lt cars, any part replaced on the pinion shaft will need the pinion position re-setting and the diff back lash,

The 914 gearbox only has the diff in the other side of the pinion to make it run the other way round and not the engine running backwards to get the 914 to move forwards

If your 901 box is the Ally one, it looks like you have taken the end off the input shaft for 1st gear and as the box had 2nd and 4th still working, the rest of the box could be still in working order, just the shafts have moved in the box and stopped the selection of the 3rd and 5th gears, has the case any damage to the out side?? if not it could be still usable, will need some photos or to inspect the box for damage report.

regards mike

Like he said - beat me to it Mike!!

Remember I owe you some cash for that dizzy - have it here waiting if you are planning on coming by at some point. Drop me a pm if you are....

[amallagh]

Mine is '66 ali case box. With all that metal floating around inside ad then running it for another 200 miles afterwards, I was told that everything in there would likely be u/s. Is this liklely to be correct ? I was told that the gear must have shattered becasue the box is full of needle rollers. Lots of fine aluminium in there as well.

Need to catch up with if the car is back from the recovery service yet.

[Histrally]

Andrew,
Really sorry to hear the news. Were you on an event when it failed?
Jerry

[amallagh]

Wondering if a clever person can advice me about the following options.

1) Is it possible to take the guts of a 914 mag case box and use then to replace the guts of my 1966 901 Aluminium case box ?
What if any parts are different ?

2) Could I replace my 901 box with a 902/1 box ? Would anything need to be changed incl clutch, flywheel, cable, etc.
The 902/1 box had Nadellea output shafts - Would I be able to simply swap the output shafts from my box to the 9012/1 box ?

3) Could I replace my 901 box with a 911/01 box ? What needs to be changed to convert from the push to pull clutch on the 911 box ?

[amallagh]

Gearbox came out today and failure mode seems quite a strange one for anyone interested. Forgive me if I get this a bit wrong as I am only repeating what Johnny at Unit Eleven has said to to me so I might have mis-interpreted what he said.
The box had been loosing oil on the way to the rally in France but I couldn't determine from where. Turns out that the shaft with the idler gear that mounts in the nose cone had come loose and the pin locating it had dropped out. This was throwing oil out of the hole near the top of the box which is why it seemed to be on one side and then on the other. Everything inside the box was working fine until I engaged reverse which must have eventaully dislodged the shaft and smashed reverse gear sending big and small bits of metal around the box. The movement of the shaft meant that 1st, 3rd and 5th cold not be located whilst 2nd and 4th seemed fine. The bits floating round the box damaged some of the selector forks and the diff crown and pinion wheel and split the nose cone. The bearings are probably goosed as well given the mileage I did after it failed.

I've bought a donor box from Mike at PRS which will hopefully be here Tuesday.
Just hoping there are sufficinet parts between them to make one good one.

Getting it all back together for Thursday before I head to Scotland for the Gain and Hour wknd with the Scottish region of the 'club we don't mention', will be very tight indeed, but fingers crossed.

I'll try to get some pictures on the failed box.

[914 KEV]

I've bought a donor box from Mike at PRS which will hopefully be here Tuesday.
Just hoping there are sufficinet parts between them to make one good one.

Getting it all back together for Thursday before I head to Scotland for the Gain and Hour wknd with the Scottish region of the 'club we don't mention', will be very tight indeed, but fingers crossed.

Andrew,

sorry to hear of your 911 gearbox failure.

Under the circumstances would it not be easier for you, not to rush the building of one good gearbox out of two, just use your ‘Red 914-6GT’ instead.

This will be the most cost effective solution, than you rushing the rebuild and finding you have to take it all out again and apart, on an oversight!

You know it makes sense; could work out a lot cheaper in the long run.

Here is a picture of you enjoy ‘The Beast’ on the 914 International in France, earlier in the year; you look relaxed, not stressed and even smiling.

[amallagh]

Hi Kev,
I told John on GaH about the gearbox problem immediately I got back from Fance and offered up my place to someone else, but I don't think there were any other takers for the full wknd and John knows we might need to come in something else.

I'm still trying to get the 911 fixed but only 50:50 at best that it will be done in time for Thursday departure. 914 of off limits I'm afraid for other work this winter.

Gear box arrived from Mike @ PRS this morning but on inspection inside it is rather worn. On the whole my failed box is still a much better start point for rebuild than the one I've bought .
1st/Reverse dogs both well and truely knackered on the replacement which I needed. Got the diff crown and pinion out of it but apart from that it is very worn throughout. Fortunately the other gears in my box were still good apart from 1st/reverse that failed.
Johnny is trying to get me a 1st gear dog teeth today but NLA from Porsche and other options very expensive. Still waiting to see if something comes off but won't know until Thursday at best. If it's not ready then we'll be coming in the daily hack I'm afraid.

John (of GaH) tried to get a car from his local OPC but no joy unfortunately !


Anyone else got an early 5 speed 901 gearbox from 911 or 912 then do let me know

[914 KEV]

I'm still trying to get the 911 fixed but only 50:50 at best that it will be done in time for Thursday departure. 914 of off limits I'm afraid for other work this winter.

is it having a major rebuild?

Gear box arrived from Mike @ PRS this morning but on inspection inside it is very worn. On the whole my failed box is still a much better start point for rebuild than the one I've bought .
1st/Reverse dogs both knackered on the replacement which I needed. Got the diff crown and pinion out of it but apart from that it is very worn throughout. According to Johnny (Unit 11) all the gears are well worn but 1st reverse is properly knackered apparently. Fortunately the other gears in my box were very good apart from 1st/reverse that failed.
Johnny is trying to get me a 1st gear dog teeth today but NLA from Porsche and other options very expensive. Still waiting to see if something comes off but won't know until Thursday at best. If it's not ready then we'll be coming in the daily hack I'm afraid.

In an emergence if you cannot get hold of the first-gear dog teeth, you can use 2-5 dog teeth, as long as you use the three braking pieces used in the 2-5 gears (two braking bands).
First-gear uses a two piece brake (one braking band). (The fifth-gear teeth on the donor box are properly usable)

No dog teeth on reverse gear.

Will have to waiting and see, what you will bring on Thursday!

[amallagh]

It's interesting what you say about using 2nd/5th dog teeth.
We did try a 1st/Rev set from a 914 box but they were different. 911 part numbers in the 914 box and 901 part numbers in the 901 box.

Could still do with another early 901 box if anyone has one just lying about !!??

Nothing major planned on the 914. 1st synchro is coicidentally something I've managed to bugger with changing down into steep tight hairpins on rallies. Rest is just some minor paintwork from stone damage plus painting the cage that has stated to loose it in places. Also several tiny things like rear lid gas stuts and some seals.

See you tomorrow night in a ????????

[amallagh]

Here are some pictures of the failed components from my gearbox.
Gearbox looks like it was rebuilt at some point in the past. Maybe someone used the wrong roll pin to secure the shaft in the nose come of the case, but for whatever reason it came loose and allowed the shaft to move.
Reverse gear split into bits and worked it's way round the box taking out the crown and pinion. You can see some of the affected bits below. You can see it also cracked the case where the broken gear hit it on the inside.
Still looking for another 901 ali case box if anyone can help.Andrew