Changing the clutch

[BDA]

Certainly, there are some assumptions that the centerline of the crank lines up with the hole in the bell housing for the input shaft - at least close enough. Judging from the previous 20,000 miles and the fact that mating an NG3 to a TC (or other Kent based motor) or Zetec is a common situation, I think we can feel pretty confident that those assumptions are good.

[GavinT]

I guess r.d. sells the cheapo alignment tool! It is plastic, the end that goes into the spigot bearing is way too big, and there is no adjustment provided.    I don't have anything I can chuck it into to sand it down while it spins so I may have to take it to a friend who has a lathe. Jeesh!

Broom stick.
Reckon you could carve the pilot end with a pen knife and have it accurate enough - only needs to be a cone shape, really. Build up the clutch fingers area with insulation tape.

The trick to this is to use a longer length of stick which better aids 'eyeing' in the 90° angle. The commercially available alignment tools are usually quite short and more reliant on close fitment than a long tool.

[dakazman]

 BDA , I have a snap-on alignment tool with different size adapters for the pilot bearing inner diameter
 I can mail it up to you.
Dakazman

[BDA]

i appreciate the suggestion, Gavin, and the offer, D'man, but the clutch alignment tool I have was easily adjusted with a bit of sandpaper and elbow grease! It fits very nicely now!

[europa88]

I've just replaced my clutch and throw-out bearing, as the engine and box were out for starter ring gear replacement. I decided to tidy up the engine bay and fit stainless coolant and heater pipes whilst the engine was out.

my original TC bellhousing was modified by Richard as described by BDA together with a new pilot bearing some 20 years ago and although I have only put about 10000 miles on the engine since then it leaked a bit of transmission oil past the seal. Richard said they all do this and its nothing to worry about. Sadly in the UK the pilot bearing seal combo is pure unobtanium, so I reused the old one. Just got the engine and box back in drove it and it pisses out now when hot! BTW NG1 series gearbox with Banks twin link.

Got to pull it again and think of a replacement. I wondered it the input shaft could be turned and a bush or bearing holder could be made to fit the flywheel? I guess the bellhousing would have to be returned to standard or buy a new one.  Happy days 

[BDA]

When I was talking to Michel at Alpine-America about parts for my NG3, he mentioned they were difficult to get. Lotus Supplies says it's still available but you'd have to contact them to be sure.

I looked at mine and it appears that the seal is an O-ring deep inside it. If yours is truly bad, it might be worthwhile to try to pick that out and attempt to fabricate a replacement with a slightly bigger O-ring. Or maybe something could be fabricated to accept a standard lip seal in it.

[europa88]

I spoke to Nick at Lotus supplies a couple of months ago and he cant get them! Richard said if you find one ...buy it!

I like the idea of an O ring mod first

[S2Zetec54]

I have an NG3 so this thread is useful to understand supply issues with once available components

So a surf found me this:

https://www.3sx.com/3sx-high-performance-billet-input-shaft-bearing-for-5-6-speeds

I wonder if a combination of talking to Richard Winter and this company would produce a useful bespoke component for those of us who have this great gearbox? Pricing would be interesting !

[BDA]

It appears those bearing/seals are meant for Mitsubishi 3000GTs. Should we assume they replace the Renault part?

If so, I would wonder if the standard 3000GT part is still available (at much lower cost). But on the other hand, having a rebuildable part would be very nice. They could out last the tranny!

[S2Zetec54]

Ah! Sorry I didn’t mean to imply that these would fit our NG Renault gear boxes….I just found something similar on google images that shows that something akin to the NG could be machined…..and if they could be rebuildable using off the shelf parts that would be encouraging and help to swallow the higher price for bespoke parts

[BDA]

I was about to post that someone could call them up and ask them the dimensions but I thought better of it and called them myself!

First, I measured what I considered were the most crucial dimensions:

shaft diameter: 25mm
bearing end diameter: 37.3mm
skinny end (throw out bearing end) diameter: 30mm

Then I emailed them and I should hear back in a day or two.

If anybody has their bearing/seal unit out and can measure it, please check my measurements. I had to use a scale graduated in 1/64ths by eyeball for the skinny end diameter so they all can stand review.

I'll post their reply. It doesn't look like anything that is that difficult to recreate in our dimensions should anybody have the inclination.

UPDATE: I heard back and our dimensions are not even close so they can't help us. Maybe a bug in Richard's ear might be helpful...

[S2Zetec54]

Well done for getting hold of them and trying….Richard is an innovative man he must be considering how he’ll solve this unobtainium part

[kram350kram]

BDA, Can the needle roller bearing be replaced?

[BDA]

I don't think so. The housing appears to be made of sheet metal and the bearing is retained by rolling the edge of the sheet metal.

[kram350kram]

Could not one of these be made on a lathe and a standard roller bearing pressed in? Doesn't look to be to complicated.