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I'm finding it harder and harder to find 3rd gear on the track changing up from 2nd, theres no grinding or notchiness getting it into gear it's mainly the position of 3rd gear is less defined and sometimes I end up over by 5th. Changes feel fine on the street. The oil in the box is fresh as I've just had the seals done but I don't know what oil my mechanic put in. Will changing it to something like Redline make much difference?

I'm guessing engine mounts are shot.
On the track under heavy acceleration the driveline will be moving with worn engine and diff mounts making gear selection difficult and inaccurate.

Perhaps time for some Stiffer competition mounts. About $90 US.




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3rd gear gets a lot of work on the track. I broke mine - 3rd would't select without a struggle, then wouldn't deselect, had to let the car sit a while before I could get it out. Synchros were shot. A six-speed solves that by sharing the load (pun intended ) better between 3rd and 4th, providing you leave the diff ratio alone (in an NB8A).

Redline will help prevent the problem, but sounds like it's too late in this case . Use it in the new gearbox .

do you have a short shifter installed? i find them a bit too finicky on the track and i'm thinking of going back to a standard shifter as i often miss 3rd and end up in 5th by mistake.

i'm not sure if that's what you're describing tho.

rossint wrote:I'm finding it harder and harder to find 3rd gear on the track changing up from 2nd, theres no grinding or notchiness getting it into gear it's mainly the position of 3rd gear is less defined and sometimes I end up over by 5th. Changes feel fine on the street. The oil in the box is fresh as I've just had the seals done but I don't know what oil my mechanic put in. Will changing it to something like Redline make much difference?

Change the bottom boot, the one on the box. Its job is to return the shift to the 3/4 plane,as well as stopping crap getting in the box, if the boot is damaged or worn it will allow you to miss 3rd gear and find that bloody 5th instead, especially coming out of turn 6 at QR, not that I would know!!!!
If your going to change oil, try Royal Purple trans oil, its bloody expensive but absolutly brilliant.

Terry

No short shifter, It feels like when you push where 3rd use to be theres a whole lot of nothing so you need to push back towards 1st to find 3rd. Engine mounts is an interesting call but could be as it only happens going 2nd to 3rd which is always coming out of corners, never on 4th to 3rd which is always under brakes coming into corners. Are the mounts hard to put in? I've found 5th a few times coming out of 2nd at 7000rpm, not a great look and lots of grinding noises
I'll have a look at the boots but thought I replaced them all a couple of years ago (might not have done the bottom one) and maybe try some royal purple and see what happens.

tbro wrote:

rossint wrote:I'm finding it harder and harder to find 3rd gear on the track changing up from 2nd, theres no grinding or notchiness getting it into gear it's mainly the position of 3rd gear is less defined and sometimes I end up over by 5th. Changes feel fine on the street. The oil in the box is fresh as I've just had the seals done but I don't know what oil my mechanic put in. Will changing it to something like Redline make much difference?

Change the bottom boot, the one on the box. Its job is to return the shift to the 3/4 plane,as well as stopping crap getting in the box, if the boot is damaged or worn it will allow you to miss 3rd gear and find that bloody 5th instead, especially coming out of turn 6 at QR, not that I would know!!!!
If your going to change oil, try Royal Purple trans oil, its bloody expensive but absolutly brilliant.

Terry

You have lost me Terry. There is the cosmetic boot on top, a heavy rubber one under that, both of which are mounted on the car as I remember them. Then on the gearbox there is a metal plate with four bolts which secures the gearlever (which the OP might want to check are still tight). I cannot recall a rubber boot on the gearbox (at least for the NB, but then again I am running a NA gearbox ).

Or am I not understanding you?

Engine mounts are not easy to put in, need to lift the engine (duh) but I believe can be done first one side, then the other - if there is nothing in the garage section here, try the big board. A hoist and an engine crane would be nice though ... I would check all the simple things first, everything is done up tight etc., the clutch is adjusted properly, engine-to-bellhousing bolts are tight, then change the mounts, then the only thing left is a problem inside the gearbox .

Good luck

I think he means the small round lower one in the link below that from memory goes on the turret.
http://www.mx5mania.com.au/product847.htm
Everything SHOULD be tight, new clutch, light flywheel and front seals done on the box about a month or so ago but I'll check. My mechanics normally really good so I'd be surprised if anything was loose.
A 6 speed box is on the cards but not for a little while, should sort out coming through the S'es in second on the rev limiter.

I stand corrected !

Never seen that one, I will have to have a look next time. You learn something every day ...

I have the same problem with mine.
I am going to try a heavy gear knob next time and see if that makes a difference.

rossint wrote:I think he means the small round lower one in the link below that from memory goes on the turret.
http://www.mx5mania.com.au/product847.htm
Everything SHOULD be tight, new clutch, light flywheel and front seals done on the box about a month or so ago but I'll check. My mechanics normally really good so I'd be surprised if anything was loose.

if you're checking this it might be worth checking the GB turret oil & replacing or refilling if necessary, given it's a 5 speed & needs to be filled separately, as opposed to the 6 speed.

There is a thread HERE which discusses the virtue of replacing the boots.
There is a guide HERE and HERE on how to replace them.

For gearbox oil, I'm very happy with Castrol Syntrans 75W/85
Cheaper than Redline and supposable as good.

I've tried Syntrans, 3 different Redlines and some other exotic synthetic. Redline and Purple were good at sorting out synchro problems, but not 3rd gear baulking. Redline MT90 is the pick of them. Syntrans was excellent at preventing my gearbox from being used in any meaningful way.
I'm hard on gearboxes and selecting 3rd has been the first thing to start going. Bruno fixed the first box by replacing all bearings (5 of them?) and re-shimming until 3rd slipped in nicely. This was then a great box until the car control system unfixed it by selecting reverse at 180kmh. The replacement box is starting to get hard into 3rd too. This accounts for the instant about-faces at EC and WP when the same faulty control system has hit 1st on the upshift from 2nd to 3rd at 7000.

Thanks for the replies. I'll have to try to find some time to get some oil and get stuck into it.

The mounts aren't too bad to change. I did it quite easily with just a floor Jack and a wooden block. Just undo one mount and loosen the other. Then I just tilted the engine each way. First side is dead easy but to do the second side it's much much easier with 2 people. I tried penrite sin 75 and found a similar problem with hesitation and crunching 3rd. Redline fixed it in my 6 speed.

If your completely missing the gear you might want to slow down the change a little. Rushing while under lateral g-force is likely a big contributor. I found I slowed down and it went in everytime and now I can change as fast without ever hitting 5th and compression locking the car.