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Winter rebuild Day 6

PostPosted: Thu Feb 20, 2014 5:34 pm
by john.p.clegg
Dear All
Well with the engine nearly ready it was time for the gearbox,pulled it out and spit it into its component parts,stripped the box for cleaning/inspection/overhaul...

2014_0220gearbox10003.JPG and


"special tools" in the foregroung required to do the job were cobbled together about 10 years ago the last time I had a go at gearbox building.

John :wink:

Re: Winter rebuild Day 6

PostPosted: Thu Feb 20, 2014 5:47 pm
by pharriso
Ah, the old Lotus 5 speed...

I still remember doing a gear change in my 130/5 & the gear lever coming off in my hand...

Re: Winter rebuild Day 6

PostPosted: Thu Feb 20, 2014 7:12 pm
by john.p.clegg
Mine was starting to get a bit "wobbly" due to the quick-shift extension having no locking mechanism....just sorted today by silver soldering a locking tag onto it...

John :wink:

P.S has anyone any secrets on how to inspect bearings...apart from looking for rust and pits and chips?

Re: Winter rebuild Day 6

PostPosted: Thu Feb 20, 2014 8:42 pm
by Chancer
Degrease them completely, dry them and stuff a few fingers through the inner race, spin the outer race up to umpteen zillion RPM with an airline blowgun aimed tangentially at the outside, listen to the sound the bearing makes as it coasts to a halt and how long it takes.

Its very subjective and comes with experience, if you have a known bad bearing and a known good or new one then listening to them will give you baseline figures.

Re: Winter rebuild Day 6

PostPosted: Thu Feb 20, 2014 8:53 pm
by oldchieft
Chancer wrote:dry them and stuff a few fingers through the inner race, spin the outer race up to umpteen zillion RPM with an airline blowgun aimed tangentially at the outside


Then watch your finger twist off when the bearing locks up!

We have all done this, but do not jam the bearing tight on your hand.

Jon the Chief

Re: Winter rebuild Day 6

PostPosted: Thu Feb 20, 2014 9:27 pm
by Chancer
I didnt specify whose fingers to use!

I keep a few severed hands from old enemies in the fridge, you never know when they may come in handy :lol:

Re: Winter rebuild Day 6

PostPosted: Fri Feb 21, 2014 1:52 am
by rgh0
Personally by the time I get a gearbox apart I normally just replace the bearings.. The Lotus 5 speed bearing set is a little expensive compared to the Ford 4 speed but if its been 10 years at least since the box was last apart then I would probably change them all. If you did not change the bearings 10 years ago and they are of a greater and indeterminate age I would certainly replace them now.

A visual inspection looking for wear on the races or balls and spinning them to see how smoothly they run will tell you if they are in good condition at this instant but will not tell you how close they are to failure which happens fairly rapidly once the surface starts to breakdown due to fatigue.

cheers
Rohan

Re: Winter rebuild Day 6

PostPosted: Fri Feb 21, 2014 5:29 am
by S2Jay
.....handy ?

Now, that's what we call a "groaner".

...and I might add, not at all appropriate for a sophisticated, intellectual and socially significant forum such as this.
:roll:

Re: Winter rebuild Day 6

PostPosted: Fri Feb 21, 2014 11:15 am
by Galwaylotus
john.p.clegg wrote:Mine was starting to get a bit "wobbly" due to the quick-shift extension having no locking mechanism....just sorted today by silver soldering a locking tag onto it...

John :wink:

P.S has anyone any secrets on how to inspect bearings...apart from looking for rust and pits and chips?

... and no blueing on race or rollers! Signs of overheating.

Re: Winter rebuild Day 6

PostPosted: Fri Feb 21, 2014 1:40 pm
by john.p.clegg
Just wondering if a small ultrasonic cleaner would be good for the bearings? as opposed to my bottle of white spirit and bristle brush?

John :wink:

Re: Winter rebuild Day 6

PostPosted: Fri Feb 21, 2014 1:57 pm
by Galwaylotus
I use petrol and a jar. Submerged the bearings overnight and all the old grease fell off/dissolved. After a quick rinse in fresh petrol and air dry they were as good as new. I greased them and put them in plastic sandwich bags until ready to reinstall. If they had been running in anything other than old grease they probably wouldn't be any good to reuse anyway. I don't believe an ultrasonic cleaner would get them any cleaner.

Re: Winter rebuild Day 6

PostPosted: Fri Feb 21, 2014 2:36 pm
by pharriso
Galwaylotus wrote: I don't believe an ultrasonic cleaner would get them any cleaner.


Agreed, but a great excuse to buy one!

Re: Winter rebuild Day 6

PostPosted: Fri Feb 21, 2014 2:40 pm
by Galwaylotus
pharriso wrote:
Galwaylotus wrote: I don't believe an ultrasonic cleaner would get them any cleaner.


Agreed, but a great excuse to buy one!

We have one! My wife uses it for her jewelry and would probably kill me if I tried to use it for car parts!! :shock:

Re: Winter rebuild Day 6

PostPosted: Fri Feb 21, 2014 3:26 pm
by john.p.clegg
Next time you have your carbs off,try it...she'll never know....

John :wink:

Re: Winter rebuild Day 6

PostPosted: Fri Feb 21, 2014 4:46 pm
by Galwaylotus
john.p.clegg wrote:Next time you have your carbs off,try it...she'll never know....

John :wink:

You have obviously never met my dear lady!! :lol: :lol: :lol: