5 speed box - stiff gate?

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tiw
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5 speed box - stiff gate?

Postby tiw » Thu Jan 10, 2019 1:50 pm

Hello,

I’m running an turbo nb with a five speed box. When in neutral, I have reciently noticed it is significantly harder to move the gear stick right into the 5/reverse gate than it is to go left into the 1/2 gate.

Is this a common issue or an easy fix?

When on the track it is making the gearchange from 4 to 5 problematic so need to get it sorted.

Any comments suggestion welcome.

Thanks

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hks_kansei
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Re: 5 speed box - stiff gate?

Postby hks_kansei » Thu Jan 10, 2019 2:00 pm

It's pretty normal, most others i've been in feel the same.

Not sure if it's part of the design though, or if it's just a matter of the detents for the left gates have worn more than the right (which would make sense since you use 1-2 every time you drive the car, but not necessarily 5-R)
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manga_blue
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Re: 5 speed box - stiff gate?

Postby manga_blue » Thu Jan 10, 2019 2:10 pm

The simplest thing to check is whether or not there's oil in the shifter turret.

Edit: ... and, if the small boot on the turret is torn, then whether or not there's dirt and crud down inside the turret.
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greenMachine
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Re: 5 speed box - stiff gate?

Postby greenMachine » Thu Jan 10, 2019 7:51 pm

5-speeds don't play well with turbos :frown: . If you like to give it the wellie, and it has a reasonable to high Kw count, it may be time to think about a 6-speed ...

But check the simple/cheap things first, and keep your fingers crossed.

:mrgreen:
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hks_kansei
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Re: 5 speed box - stiff gate?

Postby hks_kansei » Thu Jan 10, 2019 8:08 pm

greenMachine wrote:5-speeds don't play well with turbos :frown: . If you like to give it the wellie, and it has a reasonable to high Kw count, it may be time to think about a 6-speed ...

But check the simple/cheap things first, and keep your fingers crossed.

:mrgreen:



Yeah, but usually that results in either a stripped gear, or a busted casing, rather than it just feeling a bit stiff.
1999 Mazda MX5 - 1989 Honda CT110 (for sale) - 1994 Mazda 626 wagon (GF's)

tiw
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Re: 5 speed box - stiff gate?

Postby tiw » Sat Jan 12, 2019 11:45 pm

So I pulled the top off and the small rubber boot has perished and broken, and there is no oil in the turret. There is an oily film inside that is a bit gritty as a result of the broken boot. How do you clean the inside of the turret and get it working the way it should? Should I Take the turret off the gearbox?

Thanks for the advice so far......

Cheers

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Re: 5 speed box - stiff gate?

Postby Magpie » Sun Jan 13, 2019 8:33 am


manga_blue
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Re: 5 speed box - stiff gate?

Postby manga_blue » Sun Jan 13, 2019 9:00 am

The turret on my NA8 box has a detent spring holder low down on the left side towards the rear that doubles as a drain plug. You can open that to flush it all out with brake clean or somesuch. Don't know about NB8B boxes though ... could be risky unless you have a spare box to practice on first.

Edit: forget that, just looked at the 6 speed parts diagram and it's totally different. There's a plug low down at the back of the turret but it looks like it's a welch plug. i.e non-removable unless you take the whole box out.
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manga_blue
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Re: 5 speed box - stiff gate?

Postby manga_blue » Sun Jan 13, 2019 12:25 pm

Buggar, just forget everything I said. I read you had an NB8B and didn't read the thread title. :oops: :oops:
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StuwieP
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Re: 5 speed box - stiff gate?

Postby StuwieP » Sun Jan 13, 2019 3:15 pm

If the NB 5-sp turret is like the nb 6-sp turret it's lubricated from the main transmission case (unlike the early 5-sp, with a small separate oil reservoir) so couldn't you just pour some oil into the top to wash the crud down, drain the gearbox oil completely (inc. crud) and re-fill to appropriate level?

No help on the stiff feel though, sorry...
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aSimpleLife
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Re: 5 speed box - stiff gate?

Postby aSimpleLife » Sat Feb 09, 2019 11:45 am

Probably a bit late now but my 5 speed has always felt a bit notchy, especially when cold.
When I looked both rubber boots were persished and the turret oil well was dry.
So I replaced both boots and the white plastic cup bush.
Shifting has greatly improved and that notchiness is far less.

Unfortunately I now have a flow on problem with oil leaking from the turret. After 2 attempts to seal it. I am about to post about that on a more relevant thread if I can find one.


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