3rd Gear Mystery

[D34dR4bb17]

Hi,

We've had our van for just 10 days now, so I'm certainly no expert, but we've done just over 200 miles and there's one thing I'm just not understanding and that's 3rd gear!

It's a 1.6TD JX with a 5 speed gearbox. Regular driving, 1 to 2 to 3 to 4 to 5, no problems. However it's when the terrain becomes a little more demanding that things become a little more tricky.

I could be going uphill in 4th fine, the gradient slightly changes or there's a bend ahead, and I need to change down, I'm at about 2500 revs. I go to 3rd, and I lose practically all my revs, when I'm expecting them to go up. I then have to go to 2nd, before things go from bad to worse, 2nd screams so I'm literally back into 3rd after a couple seconds. 3rd now seems fine and pulls well,but doesn't tale long before it's asking for 4th to take over.

This can also happen at roundabouts where you don't have to stop because there's no one to give way to, too fast for 2nd too slow for 3rd.

So I reckon part of the problem is I'm losing my turbo, possibly. However it just feels like 1st and 2nd are very close, 3rd and 4th are very close, and there's this no-mans land between 2nd and 3rd.

I've also had strange moments where I've gone from 3rd to 4th and my revs go up, like the turbo suddenly kicks in.

The van and I still getting to know one another, but is this normal??

Cheers,
Andrew

[Mr Bean]

Yes I responded to a recent post on the same subject:
In the ten or so years I have had my 2.1 WBX with it's five speed box I have occasionally run into trouble changing up and down between second and third where I seem to find myself in a kind of no mans land. This seems to happen when I - or perhaps the box - am/is starting to get tired. It is not helped by the fact that my main transport a Focus, has the more standard shift gating i.e. first at top left.
I did think at one stage of fitting a short shift kit but as an engineer had the idea in my head that changing the velocity ratio in this way would increase required input force. Although I got to admit I have never really got into sussing out why I have this difficulty.

So to reiterate - I have come to the conclusion that I probably need to get down and dirty with the linking and gating mechanics which intention has been festering for some time now. The problem is worse for me when tired and changing down on tricky hills where slickness is really a necessity. My 2.1 WBX is powerful but has a flat torque curve so if I inadvertently let it run out of steam the next gear down doesn't do the business unless I get it at first attempt and I occasionally finish up nearly at a standstill while I press Control/Alt/Delete so to speak.
I can imagine that your 1.6 TD will need to be kept on song so am not surprised at your situation. Good luck with it anyway.

[Aidan]

what code gearbox do you have ? The code is stamped near the bottom of the case about 5" below the reverse switch housing, normal JX boxes are 3H or ASS code, they are basically the same but the ASS has a taller 2nd gear so you need to rev 1st a little more to get into 2nd, and would struggle to pull away in 2nd unless rolling, and the gap then to 3rd is smaller than the 3H but all other gears are the same and both boxes should mean the turbo stays on boost when you change up provided that you rev long enough before changing up, don't change up too early (like you would with a modern diesel with a 6 or 7 speed box) and lug the engine it's old school turbo you need 2k rpm for the turbo to boost.

[D34dR4bb17]

Thanks Aidan,

I'll have a look under the van tonight after work. You're dead right, under 2k and you're dead in the water.

To be honest changing up has been fine mostly, my fear at the minute is dropping down, from 4th to 3rd when 4th is dying I just know 3rd is not going to help me out, and 2nd is looking at my like "please no not me!!". Maybe I need to blip the accelerator just before going into 3rd, but it's a bit tricky when you're on a hill. From what I've heard from 2k to 3k the turbo is spooling up or down, so if I'm changing down at about 2.5k in 4th maybe the turbo is spooling down at that point? Also, 5th could be a bit higher, as the revs hits 3k at about 55mph.

But anyway I'll get the code and post it back here.

Cheers,
Andrew

[D34dR4bb17]

Just had a great conversation with a chap from Holman Engineering, Ian, mainly about their rear disc brake conversion kit. I mentioned this issue I've had, and he said straight off I'm going into 5th thinking it's 3rd. Basically, I think I'm selecting 3rd, but there's so much play in the linkages I'm just moving the slack about and then selecting 5th.

I didn't even consider this, but although it feels slightly embarrassing that I've been doing this unknowingly it does makes sense. It would explain why my revs hit the floor.

So need to check out the play tonight as well.

[diabolov]

Sounds like a 5 speed turbo has to be kept cooking like an old 2stroke bike! once out of the powerband and sod it!

What the Holman engineering guy said sounds interesting, and a possible easy fix too. Good luck with that.

[D34dR4bb17]

Ok managed to find it under a thick layer of grime ! It's a 3H.

There seemed to be very little play with the gear linkages from the mid point back. Some rotational play where the main shaft connects to the joint that goes up to the gear box. Loads of play in the gear stick. There's a cover and the spare wheel holder coveting the front half of the linkages, so couldn't tell what that's like. To be honest though I tried playing with skipping from 4th to 5th and 4th to 3rd, double checking underneath, and I couldn't see how I could be missing 3rd. Now I'm conscious of it I'll be more mindful when I'm driving.

So being a 3H is there anything that can be done to improve it?

Sent from my F5321 using Tapatalk

[Aidan]

3H is stock box for the JX and the gearing should be perfect for it, or at least the best available compromise which they all are to some extent or another; setting up the linkage is a case of ensuring that the fork below the gearstick is slap bang in the middle of the aluminium guide blocks (in that box above the spare wheel) in both planes when the selector ball at the gearbox end is pushed into the gearbox to the point that the spring tension isnide the box is apparent, this is neutral 2nd 3rd
but if there is a lot of play at the gearsitck or in the front bush for the linkage ahead of the splined join in the middle then selection will be less than perfect

[mrhutch]

next time you perform this shift, go into neutral, waggle the stick left and right, back to central and then go for third...

You're attempting one movement with a sloppy change and getting fifth..

(with practice this can be as slick as going straight for third!)

[D34dR4bb17]

Cheers guys for the help.

I can totally understand that it looks as though I'm hitting 5th, and your suggestion makes a lot of sense. When I get a chance to take the van, probably tomorrow now, I'll definitely give that a go.

As for the linkages, I kind of understand... mostly... but it's all new to me so I need to get under the van and work my way through it. I will get it.

At the minute the gearstick is really all over the place, I kind of half expected that from an old van.

Again appreciate all the help, I'll update back on how I get on.

Andrew

[D34dR4bb17]

Had a quick look at the linkages under the gearstick before the light faded.

It's all very loose under there. Very loose. A lot of play up and down, about 1cm which seemed like the gear stick wasn't held in by anything. Also gearstick can sit anywhere, it doesn't naturally lie between 2nd and 3rd, you have to put it there, but maybe that's normal. As well up down movement in the gearstick, there's a lot of lateral movement, and the fork rests on the bottom of the box.

All this might be pretty normal.

I got the wife too shift gears while I took a look at the box underneath. Realising now I should have checked the rear as well when I did this. But she found all the gears without problem. Unless of course its possible to be in the 3rd position in the box, but in 5th at the rear? Or she could just be better at finding the gears than me.

Driving it work tomorrow, so will see what happens.

Sent from my F5321 using Tapatalk

[Mr Bean]

Since it's been mentioned mentioned I have found myself sometimes having a lazy lift in the throttle foot when changing up such that when glancing at the rev counter I notice that my revs tend to stay up between gears. Whether this is subconsciously intuitive driving or sloppy driving is open to question but as mentioned I am conscious of the need to keep it buzzing so to speak. I'd obviously claim the former but obviously there is not too much tolerance range in what the synchromesh will cope with but there might be something in it.

[D34dR4bb17]

Well, I drove it in to work today, and there's a fair amount of hills to really test this out. OK so, it's looking highly likely that I was slipping into 5th thinking it was 3rd, because everything worked this morning. I swept neutral before going into 3rd from 4th, and I got that rev spike I was expecting. Tried it about 5+ times, and it was fine every time.

So mystery solved I guess.

The question is do I need to service my gear linkages bearing in mind what I described above. Is that totally normal?

[RogerT]

I think it’s totally normal for 30yr old linkage, and could be improved by replacing worn out parts of the linkages. No great hurry since you’ve learnt how to change gear now, but it’s what stops my other half from wanting to drive the van, so I’ll get round to it.

[mrhutch]

Well, I drove it in to work today, and there's a fair amount of hills to really test this out. OK so, it's looking highly likely that I was slipping into 5th thinking it was 3rd, because everything worked this morning. I swept neutral before going into 3rd from 4th, and I got that rev spike I was expecting. Tried it about 5+ times, and it was fine every time.

So mystery solved I guess.

The question is do I need to service my gear linkages bearing in mind what I described above. Is that totally normal?