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stiff gearbox


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#16 Purple Tom

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Posted 21 April 2005 - 08:50 AM

bugger. I really don't want to have to take the engine out again in such a short time. I think i'll just drive it for now, is there any chance at all that these components will realign themselves? I know its probably a daft question.

Thanks

Tom

#17 Guess-Works.com

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Posted 21 April 2005 - 09:01 AM

I'd give it a few weeks, If you can live with it and it don't get any worse then no harm, if it gets better then bonus. By the sounds of it the gearbox is sound, but what may happen is if one of the selectors is missaligned, then a baulk ring will start to wear, and hence you'll start playing tunes with the dogs

#18 jimbo_edmondo

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Posted 21 April 2005 - 09:36 AM

I had a really stiff gearbox as you describe not too long ago, Is it difficult to get it over to reverse as well? like two hands difficult?
Turned out somethin was bent, i was away for the week so my dad fixed it all i'll as him if he can remember exactly what it was.
I did this through playing silly games in car parks, nothin like that happen?

#19 Purple Tom

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Posted 21 April 2005 - 10:07 AM

it actually goes into reverse quite easily, its more the other way round to be honest, like getting it accross into first. I don't think having a reduced leverage KAD quickshift on is helping matters to be honest, as with the moley's on the rod it moved quite easily. If you could ask him though Jimbo that would be great.

I could put the standard stick back on, but I like the quickshift :tongue:

Thanks guessworks, i guess if the selector is misaligned it will be always slightly engaging one of the baulk rings, spinning it and slowly wearing the synchro?

Thanks

Tom

#20 Purple Tom

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Posted 25 April 2005 - 08:16 PM

right. its not getting any better, in fact it seems worse, i've taken to doing second to fourth changes now, as third has run off somewhere.

I've also noticed that when going into first, if you push it a bit too far into gear there's a very slight gear grinding noise, which doesn't happen when you're stationary.

Is this the misalignment problem that you talked about Guessworks?

Thanks

tom

#21 Guess-Works.com

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Posted 26 April 2005 - 06:39 AM

I wonder if it's just catching the reverse idler ???

ah, yes, would explain, if there's somthing which is preventing the reverse idler from going fully home into the casing then this would cause the selector to be out of line, the reason you don't feel it in reverse is that the pin on the input shaft is rounded opposed to the interlock sppol which is squared, therefore a little more give. and the 'grind' would be the cogs on the 1/2 synchro, just catching the reverse idler.

Assuming that there's something lodged in the recess which the idler fits into, there is a possibility that it could be 'blasted' out with the box still in the car...

Use some of that STP engine flush in a vain attempt to looosen as much C**p in the box as possible, then drain the oil... Then if you can ( with reverse gear selected, pour (pump) petrol down the dipstick hole, and see what comes out of the drain plug, probably even more C**p... if you keep moving the gears around it may just free up...

#22 Purple Tom

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Posted 26 April 2005 - 08:25 AM

hmmm, could I have caused this when I removed the layshaft to fit a centre pick-up pipe? What could be causing the problem, some dirt or something similar, maybe a tiny bit of gasket thats dropped into the 'box?

I understand what you are saying to do, so when its in reverse the idler is moved across, hopefully exposing whatever it is thats causing the problem, and allowing it to be (hopefully) flushed out of the way?

Tom

#23 clubman katie B.F

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Posted 26 April 2005 - 05:51 PM

have just thought tom.....when i got broken into, the back door window got smashed and there was glass everywhere. the gear box was sat underneath the engine. is there anyway broken glass could have gotr in there

#24 Guess-Works.com

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Posted 26 April 2005 - 07:06 PM

Yes, you get my drift...

#25 Purple Tom

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Posted 26 April 2005 - 10:53 PM

ok, i tried what you suggested today Guessworks.

I put the car up on blocks of wood under the front floorpans, took the wheels off, and put a tin of Comma Engine Flush in (nearest we had to STP in stock at home). I then ran it for about half an hour, moving through the gears, and spending lots of time in reverse, through varying revs, then quick swaps between forwards and reverse.

I then drained the oil when it was hot. I refilled it with fresh oil, and it seems to have made a tiny difference. It is a bit less notchy in neutral, but still quite stiff. Gear changes down the box have improved, and enagagement throughout the gears is better. BUT - three times in 30 miles it refused point blank to go into third, requiring a drop back into second, at which point it would drop into third lovely.

I think i'm just going to get a recon box for it, and use the opportunity to rebuild the one thats in at the mo, using the opportunity to learn about gearboxes.

Tom

#26 Purple Tom

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Posted 26 April 2005 - 10:54 PM

oh yeah, forgot to mention, the gear grinding noise when going into first has completely stopped now.

#27 Guess-Works.com

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Posted 27 April 2005 - 10:38 AM

well, worth a try.... but I think you're right, box out to find what is the cause.

I'm as intrigued as you..

#28 SCURVY DOG

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Posted 28 April 2005 - 01:43 AM

had a similiar problem a few years back

turned out to be the bush inside the reverse gear had slipped so was sticking out

stoping the gear from returning back fully and stopping the

selectors from lining up

some of the reverse gears have a split bush these seem to give the most

problem was easy to fix just pressed the bush back in

may not be the same

but sounds like the same problems i was having




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