Lotus 5 speed: Trouble engaging 4th

[gjz30075]

Is the box bolted up to the engine? Might make a difference with diagnosis.

[mbell]

Engine and box currently separated. Having them together may limit the forward movement of the input shaft when selecting forth, especially with missing upper cover, but I am struggling to see how that would prevent engagement as my initial thought was the issue was too much movement!

I took the box out via the engine bay so it had a good shake and change of angle. So wondering if what ever it was has been re-aligned or dirt or something dislodged.

It's a good point to test to test the box fitted to the engine thou. I probably pull the cover off and have a look and then test it bolted up to see if that changes it.

Current think at the minute is to fit the engine and box back as a unit so I can be sure its ok.

[john.p.clegg]

Mark
While it's out take the time to look at the spring detents ( side and underneath ),you can change springs or shim them for tighter/looser shifts.

Also have a look at the selector shaft finger clearance in the 1/2nd,3/4th fork.In your case especially 4th.

http://www.lotuselan.net/wiki/FD_-_Gear ... ifter_%2B2

John

[mbell]

Thanks John, will have to look at this. It hasn't be too bad but some time is a little trick to get out of gear, meaning you get half way in to the next gear. 5th is especially stiff to come out of.

[mbell]

Fault confirmed, input/1st shaft play. Probably 4 to 5mm play. Just enough engagement to work with no load, not enough to work under load.

Everything else with the box seems good, so need to decide if to just fix this or go thorough entire box and replace all the bearings.

Seems sensible to do but I don't have any if the tools or experience which makes me a little reluctant!

[john.p.clegg]

I replaced all my bearings a few years ago,the bearings ( well some of them ) are not easy to get and the cost was somewhere around ?300,you do need special tools unless you are able to make/adapt bits of scrap etc..

John

[dougal9887]

Hi Mark,

I'm sorry I can't help with your problem, but perhaps whilst you have the gearbox apart, you can help with mine!

If you have the output shaft apart, can you let me know how the speedo gear is attached to the shaft and if there seems any possibility of it slipping. This is in connection with a speedometer erratic drive problem I have.

Many thanks,
Dougal.

[mbell]

Thanks John, what kind of condition where the bearings in and any idea of mileage?

My car is at 48K and apart from the input bearing the box seems in decent condition from a first pass. So am leaning towards just the input bearings, as I am likely to do more damage trying to rebuild it with limited skill, missing the right tools and limited ability/tools (Hammer, drill, saw, vice) to make suitable tools. Would be good to hear peoples experience with wear on the box to try make a more informed decision.

Also read the manual last night I failed to find the instructions to remove the input/1st motion shaft. It seems they forgot to include it in my version! Looking at the drawing it looks like remove the front cover and then the two shafts & bearing should "just" come out the front with out need to remove anything else. Is that right?

Dougal: I take a look if I open that bit of the box up but not certain I will be pulling the rear housing. Looking at the parts diagram:
http://www.lotuselan.net/wiki/FE_-_Gear ... rnals_%2B2

Item 29, is the drive and would guess the 90 Degree unit connects to that directly. So more likely to be a fault with that unit.

Thanks,

Mark

[john.p.clegg]

Mark
From memory ( years ago...) a special tool I had to make up was to fit over.....???

Maybe you should read this first..

http://gglotus.org/ggtech/elan-5spd/elan-5spd.htm

John

[john.p.clegg]

Mark
Found it ,the special tools are on Page 53 of section F and the one needed is 18G 284 AAC/2

John

[mbell]

Thanks John.

I've read through that document a few times. Unfortunately for someone like me with limited experience in this area it isn't as detailed/specific as I would like and the photo's are two small to clearly see what is refereed to. That said I am planing on making a few of the changes, like wider input bearing, washer on the selector link pin and look at the alignment of the selectors.

18G 284 AAC/2 looks to just be a slide hammer/puller, probably with the right thread to fit some of the shafts. I need to revisit the that section for the manual and look at the tools and also check I haven't missed the instructions on removing the input/1st shaft.

I am presuming to get the input & 1st shaft out I just need to remove the front input shaft housing and then they pull them out if a I can find a suitable tool. Is that right or does more of the box need to be striped down first?

Still interest to hear experiences of bearing wear on this boxes. Will be heading to the UK in couple of weeks so planning to pick up the parts while I am there, so need to decide what to do...

Cheers,

Mark

[john.p.clegg]

Mark
18G 284 AAC/2 is not a slide hammer but a "piece" which fits over the first motion shaft to allow it to be removed,not something I would recommend to someone with limited tools.
There are lots of "special tools" to get the job done....not for the faint hearted.

John

P.S. my box was of unknown origin so decided on a full rebuild just to be on the safe side

[mbell]

Thanks John, my mistake. 18G 284 is the slide hammer, 18G 284 AAC/2 is attachment for input shaft. I will take a close look at it in the workshop manual.

If I can find a suitable tool I feel reasonably happy to do the input/1st motion shaft and bearing myself. A full strip down is more questionable as more tools will be needed. I don't have a lot of options thou as its not a very common gearbox in this part of the world so I am not very comfortable taking it somewhere to get it worked on.

Thanks again,

Mark

[mbell]

At home so can look at my workshop manual. I was wrong again. 18G 284 AAC/2 is a spacer that fits between 4th gear and the bearing so that as you draw out the shaft the force is applied to the outer bearing race not the inner. 59a 60a and 61a are to connect the puller to the shaft.

Probably not to too hard to make out of a suitable piece of pipe or something.

[john.p.clegg]

Mark
Some of the tools I had to "knock-up" to rebuild the box...

The letter C is the part in question..

Would you like me to dig out the receipt for the bearings/supplier?

John