Gearbox leak - Planning for a gearbox and engine pull

[nmauduit]

...the problem

in case you need an alternate route, sleeving the yoke would restore a sirface finish for quite a while (speedi sleeve or equivalent, no affiliation)...

or even quicker when in a pinch
https://www.youtube.com/watch?v=CfupzecbCLE
would not try the above myself, but TIG recharging and repolishing the surface could be done quickly and last a while, too, without the requirement of sourceing the sleeve

[jono]

Yeah considered that, and the Speedysleeve route, but I can get the prop shortened and balanced across in Newcastle tomorrow while I wait for ?58 + VAT so for sake of certainty that's my favoured route.

[2cams70]

Personally if I was in your situation my preference would be the good condition secondhand route through Sue Miller. She's probably supplying secondhand because she knows the new ones are sh**. In the very unlikely event it too turns out to be a dud you haven't made any changes to the propshaft so no harm done and easy peesy to fix.
If the length of the yoke is wrong my immediate thoughts would be turning to thinking about what else is possibly wrong with it but that's just me.
My personal experiences with speedy sleeves haven't been good ones. A lot of them are stainless steel which is incompatible with a lot of other metals as a bearing surface. The wear rate where the oil seal rubs is also much greater than with the virgin material. In this case you'd also face the difficulty of having to turn down the yoke surface because the same OD must be preserved for the bush. All in all too much is in the too hard basket in my opinion with these.

[SENC]

Here are a couple pictures of mine. jono - are you saying the tailshaft extension bottoms out on the flange of the new yoke?

[jono]

Henry,

Exactly that - the 'nose' of the 'U' is 10mm further forward of the axis of the cross joint so it bottoms out and it's then impossible to get the diff flange and end prop flanges to meet up as the prop is effectively too long.

The good news, for me at least, is Kelvedon have just been on the phone and, to their good credit, have apologised and acknowledged the problem and offered me their last original NOS yoke in exchange and have asked for my old one so they can have 'correct' ones made.

..bums are going to be kicked at their suppliers it seems.

This is great as I can now avoid the prop shortening trip tomorrow

[rgh0]

I always try to avoid modifying one part to accommodate an error or difference in another part. This leads over time to a cascading number of changes which gets to the point where repairs or rebuilding is impossible due to all the changes overtime and you need to go back to standard and start again

cheers
Rohan

[2cams70]

Well done. Stock up on the good secondhand ones now!

[SENC]

Henry,

Exactly that - the 'nose' of the 'U' is 10mm further forward of the axis of the cross joint so it bottoms out and it's then impossible to get the diff flange and end prop flanges to meet up as the prop is effectively too long.

The good news, for me at least, is Kelvedon have just been on the phone and, to their good credit, have apologised and acknowledged the problem and offered me their last original NOS yoke in exchange and have asked for my old one so they can have 'correct' ones made.

..bums are going to be kicked at their suppliers it seems.

This is great as I can now avoid the prop shortening trip tomorrow

Good deal. I'll get on the horn with them about a replacement - hopefully they'll get some new ones made up quickly.

[SENC]

Spoke with Kelvedon right after you did - they acknowledged the issue and that they are working with their manufacturer, but I haven't heard since a resolution plan. Does anyone have a NOS yoke? My old propshaft is fine, just need to rebuild the ujoints and replace the yoke if I can find one.

I was not able to find a NOS bushing to replace the repro that wouldn't accept the yoke, so I ordered repros from a couple other vendors. Lotus Marques in Australia makes a solid bushing from brass (with the oil channel) that they reported they use regularly in the shop and assured would work. I installed it today and confirmed it is a nice fit in the tailshaft extension and will accept the yoke. The other repro I received looked identical to the one that didn't work, so I'll be returning it.

So, gearbox is back together. Next step is reinstalling the sump pan (socket head screws arrived this week), then will do some engine bay cleanup while awaiting a Kelvedon yoke resolution or locating a NOS yoke.

[joe7]

Awhile back a forum member with a Plus 2 in CA was having some problem with his snap ring trans. One of his ideas, after consulting with his mechanic, was to shorten the drive shaft. After seeing the pics on this thread, he very well may be correct!

[2cams70]

One of his ideas, after consulting with his mechanic, was to shorten the drive shaft

It didn't fix his particular problem though and he never got back to us with an update or final resolution.

[elanman999]

Jono,
I know it's no use to you now but this problem has been around for two years. See :- viewtopic.php?f=37&t=39808

I told two of the usual suspects then, but they refused to acknowledge the issue. When I checked things the problem was that the welsh plug was just about touching the end of the GB tail shaft. So it may or may not be OK.

I went the same route as you and shortened the proshaft. I also had it done in Newcastle, when I went there it was as if they could only shorten it by 1 in, but I did make them see sense in the end. 10mm was fine.

2cams, I did try a good few UK prop shaft suppliers and the incorrect item was the only one available and is called a "Cortina" yoke, so yes keep hold of good S/H yokes.
Cheers
John

[SENC]

Was about to reinstall the bellhousing as a final step in the gearbox rebuild and decided to test fit the reverse light mechanism - glad I did because I found the threads totally stripped in the box. Unfortunately, there are no fine thread helicoil kits to be found nearby, so completion will have to wait for an Amazon delivery this week.

On reinstalling the detent springs I found they didn't have the recommended .335"-.375" clearance when resting in the cover and would need shims. M3 washers worked perfectly, and was impressed with the difference in engagement in those detents over pre-rebuild.

Kelvedon has not yet resolved the yoke/propshaft issue, so I'm planning to return the unit. All of the usual sellers that carry new yokes seem to have the same, incorrect yoke. TTR uses the same yoke (or at least one that is dimensionally similar), but in talking with them it seems they've shortened their propshafts 9-10 mm in order to compensate. I've ordered a propshaft/yoke unit from them and will report back when it arrives.

[2cams70]

What are the actual length dimensions of an original Elan propshaft yoke? One would assume it's the same as Cortina but maybe it actually isn't??

[SENC]

What are the actual length dimensions of an original Elan propshaft yoke? One would assume it's the same as Cortina but maybe it actually isn't??

These represent the dimensions of my original yoke (blue) and the one provided by Kelvedon (red). I did this for relative comparison more than specific measurement, so wasn't trying to be perfectly accurate and may be off fractionally.

Yoke length from center of the ujoint to tip is the same on both, the differences are in the inner dimensions, which caused the fitment issues it seems many have had. Perhaps the Cortina yoke is the one sellers are providing assuming the same?

As for the propshaft/yoke combination, I measured my original and the Kelvedon one at the same 69.85cm. TTR says theirs measures at 68.9cm due to shortening their propshaft to compensate for the yoke. Will confirm on arrival.