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Gearbox Saga


Unfortunately in May I lost 2nd gear and it took awhile to fix and not sure it is 100% so here is the saga so far.

 

The Fateful Night
When the gearbox decided to act in a manner not in keeping with a 5 speed gearbox it didn't go with a bang or massed grinding, it just disappeared. After exiting a particularly nice roundabout and changing up from 1st there was no drive available. All other gears where fine.
To say I was less than happy at this would be an understatement as I had just fixed a number of other minor gripes and the car was running the best it had in a long time. This may be half the reason it went now due to the extra power etc.
Prior to this there had been no indication that there was any gearbox issues. Knowing that the gearbox can be a problem I had purposefully checked it out before buying the car, and it felt better than others I had tried previously.
I put it down to bad luck and just another pat of owning such a nice car.

Garage Hunting
Initially after the problem I didn't feel I had the necessary equipment and time to do all of the gearbox work myself. I don't have much of an area to work on cars, as the drive is mainly gravel and therefore not suitable for ramps or jacks. A kind over from a friend (Simon , thanks for the offer) to use his garage area was possible but due to him going away and other issues I decided to look for a garage to do the work.
Well it became a major thing to find someone who was prepared to even touch the car, I was happy they where competent, could do it reasonably quickly and did charge a fortune. On a recommendation I contacted a company regarding the actual gearbox repairs (The gearbox Shop at Thorney). They offered to take out the gearbox at a reasonable rate. Well as time passed and yet more excuses came up why they couldn't have the car in that week I was getting a little impatient. I had bought a small Fiesta to get me around in but that just made me even more desperate to get the car back on the road.
Can understand the garage's reluctance to take the job on. It's was a bit more involved than the thought, would be taking up ramp space for possibly a long time and is not something they wanted to get wrong. To be honest I don't mind their reasons just been better for them to tell me.

Out it comes no more waiting
After a frustrating week I had had enough and a weekend blitz was in order. Got the car up onto axle stands in my limited area and started to take apart the rear of the car. The Lotus service notes and parts list books where invaluable in helping with the right order and not missing bits. A Saturday's work and the gearbox was about ready to be parted.

With the help of Doug on the Sunday we where able to get the box fully out of the car leaving a gaping hole where it used to be.

Into the back of the Fiesta and up to the Gearbox specialists to work their magic. A couple of days later they came back with the verdict. Well the syncho's are ok but better bring your parts list you need to go shopping.
The 2nd gear teeth that engage with the synchro ring had worn away. Additionally at some point the primary shaft 1st gear had chipped a tooth. So looking at some major mullah and delivery times.
2nd gear no problem but the primary shaft was an issue.

The Alternatives
Whilst weighing up the costs of this gearbox I decided to look at all of the alternatives available for the Esprit.
Looked at replacements such as Quaife, which was serious money and not suitable for road use. Maybe once they get some Helical gears ? and lower the price by 8K.
Gearbox rebuild by Micheal Motorsports, but never got a response from them ?
There was also talk on the forums about using the Renault 21 Turbo gearbox. Looked through all of the options and was worth a try as a short term solution. Found a secondhand good gearbox from a Phase2 21 Turbo for £200 and off back to gearbox shop to move the selector mechanism over.

If it isn't one thing it's another
The gear selector mechanism on the Renault box is a two pivot affair where one cable connects onto the rear of the box and pushes the selector rod in and out and another cable twists the rod. this is all on the left hand side. The S4s mechanism is a single translator on the right hand side.
Not up to totally redesigning the cable mechanism for the car it was decided to take the rear casing off the Lotus box and fit to the Renault box. All looked good and was going well until the pivot shaft interlock guide had different threads. This bit holds the selector guide in position so is vital but not under any stress.
A quick cutting of some new threads and all was back in business.

Finally time to match it up
Ironically the 2nd gear had turned up for the Lotus box and it was decided that the primary shaft gear could be cleaned up as the chip on one tooth wasn't serious if the edges where taken off.
I was semi committed to the Renault box route at this point so soldiered on.
Fitting back into the car was a lot easier than expected. Everything seemed to slot in with minimal fuss, I think a lot of that is sheer luck rather than design, but I ain't moaning.
Unfortunately I didn't get any pictures of the rebuild as I was up to my arms in muck and more worried about getting it back into one piece.

All systems go
It was a nice day when everything was back in place, I thank my forethought for thinking about marking where all the electrics went. There was a lot of swearing at times, some knocked and burnt knuckles and a few drops of blood into the mix but it all started and moved with 5 forward gears again.
A few tentative forays out steadily raising the pressure on the engine and gearbox with a good check on each return. News was all good and it felt good.

A suggestion and interesting pont is to make friends with some of your local garages. I had issues getting hold of some good oil, grease and other silly bits. The local auto factors where no use and just where not prepared to put any effort into it, Toyota garage was unhelpful if it wasn't a Toyota despite being a good customer of theirs for over 6 years. My local tyre company helped out immensely. Bought stuff at trade price for me, I slipped a few extra bits their way for the effort they put in. Phoned around to find the best equivalent oil's for me. Let me borrow some tools and equipment and basically very helpful. They basically felt happy helping me as it was a Lotus and not trying to get money out of me because it was a Lotus.
What have they gained, well I will certainly be getting tyre's via them, the odd bit of work on other cars, recommending them to friends and colleagues. And all for just being nice and a little respect.
Another surprising element was that a good proportion of the fitters are the stereotypical young hot hatch brigade who many sneer at. They where more helpful, polite and interested than the so called normal people who just where basically a$$holes and treated either as a rich idiot who knows nothing or with absolute jealousy. Sad really.

Living with the gearbox
So far I have not experienced any problems with the gearbox and have had times where I was going full out. Especially the time with the MLOC group where it was a lot of 2nd and 3rd gear bends on narrow roads. Lots of short acceleration and heavy braking.
There has been an occasional clutch slip on full WOT when clutch was dumped a little too harshly but I think that is down to a slight oil contamination of the clutch. It isn't 100% repeatable and goes away after slipping for a little bit. Almost as if it burns the oil off. I think this is due to a slightly leaking rear crank seal but that's another story.

What next
I intend to keep the renault box in place at the moment and use the Lotus box as a spare if anything goes wrong.
I'm also investigating the primary shaft replacement available via Bell Performance. This apparently cures a major issue in the flexing of the primary shaft under high torque which causes premature failure of cogs and synchros. Hopefully they can make a shaft that mates to the Lotus flywheel. I will keep this page up to date and let the UKLotusEsprit Yahoo group know of any issues I have in the future.