4 speed gearbox - speedo angle drive

[jono]

Hi all,

I am trying to do all of the things which are easiest done before the body goes back on.

I need to fit the angle drive (Spyder chassis) however as I bought the car as a collection of boxes of bits I have no record of which way the output face from the angle drive points and where the speedo cable routes (eg. under or over the starter motor).

Also, I have heard something about an o ring being needed to seal the speedo angle drive to the box - can anyone advise where this goes?

If anyone could post up a photo or two it would be greatly appreciated.

Many thanks, Jono

[CBUEB1771]

Jono,
There is an o-ring seal on the outer diameter of the speedometer driven gear bearing. The bearing is the cast piece (105 E 17269) that slips into the gearbox tail housing and held in place by the pressed sheet-metal fork. Then there is a round paper gasket that goes between the bearing and the angle drive. I have forgotten the exact routing but the work shop manual show the angle drive facing forward and up, about 45 degrees to the horizontal. I am sure the cable is routed over the starter motor. The orientation of the angle drive is easy to adjust from below with the engine and four speed gearbox in place, so if you don't get is just right you can correct things easily later.

[elansprint71]

"The orientation of the angle drive is easy to adjust from below with the engine and four speed gearbox in place, so if you don't get is just right you can correct things easily later."

Is that true with a Spyder chassis when the body is on?

EDIT: perhaps I should qualify my question above, I don't know the dimensions in the +2 but it makes a difference in the Elan, there is less room with the tubular chassis. Apologies.

[sveris]

Is the Elan angle drive the same as the one used in Europas? Just wondering. If so, lubrication is the key to longevity.

[bcmc33]

I have heard something about an o ring being needed to seal the speedo angle drive to the box - can anyone advise where this goes?

Jon,

In answer to your question - there are two (2) 'O' rings on the speedo drive. See picture:

[Robbie693]

- there are two (2) 'O' rings on the speedo drive

Oh no! I didn't realise there were two 'O' rings! I replaced the big one a while ago but still have oil coming out from the part after the knurled collar. Could this be the culprit? Is the knurled collar supposed to be tightened firmly to prevent leaks? - I thought the right angle part of the drive was supposed to swivel at this point..?

Robbie

[CBUEB1771]

In answer to your question - there are two (2) 'O' rings on the speedo drive.

Brian,
Very interesting, I have never seen a version of the driven gear bearing (105 E 17269) with two o-rings. The bearing in my +2 has the larger o-ring to seal the fit between the bearing and the gearbox tail housing but a paper gasket between the bearing and threaded adapter (026 F 0100). The depiction in the service parts manual is consistent with what I have (only one o-ring listed). To address Robbie's comment the knurled nut on the right-angle gearbox must be tightened on the threaded adapter. The gearbox is not intended to swivel or float in use, it would leak like a sieve if not tightened.

[bcmc33]

In answer to your question - there are two (2) 'O' rings on the speedo drive.

Brian,
Very interesting, I have never seen a version of the driven gear bearing (105 E 17269) with two o-rings. The bearing in my +2 has the larger o-ring to seal the fit between the bearing and the gearbox tail housing but a paper gasket between the bearing and threaded adapter (026 F 0100). The depiction in the service parts manual is consistent with what I have (only one o-ring listed).

Russ,

I see what you mean regarding the parts listing does specify a gasket.

When I checked to answer Jon's question I took the gear off the 5 speed box as it is sitting on the workshop floor, and it does have a small "O" ring as shown in my picture.
But, I now take the gear of the 4 speed box that is also sitting in the workshop, and low and behold, it has a face gasket.
I consulted my Lotus gearbox guru who said it should be a gasket. So the parts list and you, Russ, are correct - there is only one (1) "O" ring specified.

However, the PO who did this "O" ring mod has my respect because I like it better as an engineering fix than a gasket (IMO of course) - and it will stay that way on the 5 speed.

[CBUEB1771]

However, the PO who did this "O" ring mod has my respect because I like it better as an engineering fix than a gasket (IMO of course) - and it will stay that way on the 5 speed.

Brian,
I agree that the second o-ring is a better solution, that is what made me search the parts book to see if there was a second version of the driven gear bearing. The paper gasket becomes saturated very quickly and at that point functions more like a wick to suck small amounts of lubricant out of the gearbox.

[Robbie693]

In answer to your question - there are two (2) 'O' rings on the speedo drive.

To address Robbie's comment the knurled nut on the right-angle gearbox must be tightened on the threaded adapter. The gearbox is not intended to swivel or float in use, it would leak like a sieve if not tightened.

Thanks Russ, I'll have to have another go. Regarding the paper gasket, when I bought a new 'O' ring from Paul Matty they said the paper gasket was not in their spares list and suggested I used RTV instead. I've not seen gasket paper to make your own for a long time so I did the RTV thing and it seemed to work - until I disturbed it trying to tighten the adaptor whilst fitted to the box!

Regarding accessibility, I have a spyder chassis and it is possible to get at the drive but it helps a lot to drop the gearbox down a bit by unbolting the support.

Cheers

Robbie

[CBUEB1771]

Regarding the paper gasket, when I bought a new 'O' ring from Paul Matty they said the paper gasket was not in their spares list and suggested I used RTV instead.

You might try one of the other usual suspects in the UK. Ray at RD Enterprises in the US supplies this paper gasket.

[jono]

Thanks for all your useful comments guys and to Brian in particular for his useful 'mod'.

I spent last Saturday pulling the engine and box just to wrap PTFE around that troublesome single bolt between the bellhousing and box (following a recent thread on here) so I want to do all I can to try and achieve a leak free gearbox

...time will tell I guess, it is a Lotus after all!

Thanks again, all.

Jon