Lotus Elan

Oilite Crankshaft Spigot Bearing

PostPost by: Gopherit » Tue Jun 02, 2020 7:43 am

Does anybody know a source in the UK for the oilite crankshaft spigot bearing (17x21x16mm nominal size) needed to fit an early CR Gearbox to a 6-Bolt crank?

Yes, I know Dave bean does them in the USA and I do have the facility to get one made, but the latter would need accurate manufacturing ID/OD which I do not have and the former would be unjustifiable expense for a basic £4 bush!
Nearest standard off-the-shelf bush I have found is 16x21x20 which would mean reaming to fit shaft.

paul
It's not a rehearsal
Gopherit
Second Gear
Second Gear
 
Posts: 60
Joined: 18 Oct 2007
Location: Guildford, Surrey

PostPost by: Mazzini » Tue Jun 02, 2020 8:03 am

By coincidence I was just trying to persuade a friend to make me a couple.

They are a fragile thin thing. There can't have been many made by Lotus as by the middle of '67 the supply of C/R boxes must have just about ended.
User avatar
Mazzini
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1880
Joined: 11 Dec 2010
Location: NE UK

PostPost by: rgh0 » Tue Jun 02, 2020 10:07 am

Dave Bean lists the 17 mm early shaft into the 21 mm hole in the 6 bolt crank oilite bushing as part 036-E-6008. At 2 mm wall thickness it is marginal and not easy to make accurately and fit into the crank !

cheers
Rohan
User avatar
rgh0
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 7488
Joined: 22 Sep 2003
Location: Melbourne, Australia

PostPost by: Craven » Tue Jun 02, 2020 10:19 am

I have had several C/R input gears/1st motion shaft ground to the appropriate size to mate with the standard 6 bolt needle spigot bearing.
Craven
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1073
Joined: 14 Sep 2013
Location: south coast uk

PostPost by: rgh0 » Tue Jun 02, 2020 10:41 am

Craven wrote:I have had several C/R input gears/1st motion shaft ground to the appropriate size to mate with the standard 6 bolt needle spigot bearing.


Yes that is what I would do if going down that path, easier than boring out the end of the crank :D

cheers
Rohan
User avatar
rgh0
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 7488
Joined: 22 Sep 2003
Location: Melbourne, Australia

PostPost by: elancoupe » Tue Jun 02, 2020 10:45 am

Craven wrote:I have had several C/R input gears/1st motion shaft ground to the appropriate size to mate with the standard 6 bolt needle spigot bearing.


I have done this as well.
Mike
elancoupe
Fourth Gear
Fourth Gear
 
Posts: 972
Joined: 11 Sep 2003
Location: Spam-on-Rye

PostPost by: mark030358 » Tue Jun 02, 2020 10:58 am

Is this what your looking for..

https://qedmotorsport.co.uk/lotus-twin- ... -con-rods/

Cheers
User avatar
mark030358
Fourth Gear
Fourth Gear
 
Posts: 917
Joined: 29 May 2004
Location: Willaston, Wirral

PostPost by: Mazzini » Tue Jun 02, 2020 11:32 am

Thanks, but sadly not. Burton don't manufacture the right size spigot bearing to mate an early close ratio gearbox with a larger first motion shaft to a later 6 bolt crank which has a smaller roller bearing.
User avatar
Mazzini
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1880
Joined: 11 Dec 2010
Location: NE UK

PostPost by: vstibbard » Wed Jun 03, 2020 6:17 am

I've done the same as Craven for the last cars I've fitted with CR boxes.

Cheers

V
vstibbard
Fourth Gear
Fourth Gear
 
Posts: 571
Joined: 22 Jul 2008
Location: Sydney, Australia

PostPost by: reb53 » Wed Jun 03, 2020 7:15 am

Gopherit wrote: Nearest standard off-the-shelf bush I have found is 16x21x20 which would mean reaming to fit shaft.
paul


I was once given to understand that reaming Oilite bushes was a bad idea as the reamer would smooth over all the fine holes that were meant to retain, and transmit, oil.
Bearing in mind, ( haha, little joke....), that Oilite bushes are basically compressed/sintered bronze dust, that seems possibly correct.
Or just another one of those myths..?
reb53
Fourth Gear
Fourth Gear
 
Posts: 771
Joined: 09 Apr 2005
Location: Napier New Zealand.

PostPost by: Mazzini » Wed Jun 03, 2020 8:05 am

reb53 wrote:
Gopherit wrote: Nearest standard off-the-shelf bush I have found is 16x21x20 which would mean reaming to fit shaft.
paul


I was once given to understand that reaming Oilite bushes was a bad idea as the reamer would smooth over all the fine holes that were meant to retain, and transmit, oil.
Bearing in mind, ( haha, little joke....), that Oilite bushes are basically compressed/sintered bronze dust, that seems possibly correct.
Or just another one of those myths..?


The Oilite bearing, which I believe was original, crumbled when I first tried to mate the engine to the box, it's fragile stuff. Subsequently I used a phosphor bronze bearing, but as Rohan pointed out, the wall is only 2mm thick. With perfect hindsight, I should have followed Vaughan's advice and machined the first motion shaft down to size.
User avatar
Mazzini
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1880
Joined: 11 Dec 2010
Location: NE UK

PostPost by: Gopherit » Wed Jun 03, 2020 9:42 am

Many Thanks for all the contributions - think I am persuaded to grind the input shaft end, but from those who have done this was any heat treatment necessary pre or post final grind to size or is the (presumably alloy steel) capable of being ground down without any heat treatment being involved?

paul
It's not a rehearsal
Gopherit
Second Gear
Second Gear
 
Posts: 60
Joined: 18 Oct 2007
Location: Guildford, Surrey

Total Online:

Users browsing this forum: No registered users and 3 guests