Gearbox or clutch

Gearboxes, clutches, diffs, wheels & tyres....
Threesevens
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Gearbox or clutch

Post by Threesevens » Sat Jun 06, 2015 5:40 pm

I get the running at last after sorting out the SU carb issues and went out 2 or 3 times driving in the last few days and thought everything was fine.
Until yesterday!
It started to get a little bit difficult to engage reverse gear without it crunching a bit.
Been out in it twice today and it hasn't gone away despite me saying my prayers last night!
As you will probably know I am a bit of a mechanical novice so I am not sure what the likely cause is.
With the engine switched off I can engage reverse gear without any problem.
Not sure if this means it is a clutch or gearbox issue but I can engage all forward gears normally whether the engine is running or not.
Any comments or suggestions would be very much appreciated, I am not sure where to start. :(

One bit of good news I had the engine and underbody steam cleaned and the guy said how good it was underneath. :)

Look forward to hearing from anyone who can help.

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DKWW2000
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Re: Gearbox or clutch

Post by DKWW2000 » Sat Jun 06, 2015 6:03 pm

Have a look at your clutch fluid, if it has been standing you might find it is sludge :o I would bleed the the clutch & check the rubber hose for deterioration.
RX7 FB S3 - RX7 FC TII Vert
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ian65
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Re: Gearbox or clutch

Post by ian65 » Sat Jun 06, 2015 6:26 pm

iffy clutch hydraulics are typical in cars that have been off the road for a number of years as yours has. Rust forms in the bores of the clutch master and slave cylinders and once you start using the car again, the rust damages the seal inside the master and slave and causes them to leak..... as the fluid leaks out, it gets replaced with air which then means that your clutch doesn't work fully and you have difficulty selecting some gears with the engine running.

If you look at the clutch slave cylinder which is on the top of the bellhousing just below the oil filter, you will see a black rubber sleeve on it.... pull that sleeve off the slave cylinder and see it there is hydraulic fluid in it.... it there is, then that's your problem..... the clutch master cylinder can also leak, usually down the inside of the bulkhead above the pedals.

Given the very low mileage you car has done during the last 10 years, you should really replace both the clutch master and slave cylinders...... it's an hours work to change them but for some bizarre reason, UK suppliers charge an absolute fortune for new clutch and slave cylinders. The best place to get them from is Rockauto in the USA...... dirt cheap and they arrive within a few days of ordering them.

you can get repair kits for them but to be honest, they are just a short term fix...... new complete cylinders are so cheap from Rockauto that it isn't worth trying to fix your own.

.
1986 Series 3 13B Turbo II
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1992 Peugeot 205 1.9 GTI
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Threesevens
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Re: Gearbox or clutch

Post by Threesevens » Sat Jun 06, 2015 10:50 pm

Thanks for your prompt feedback. I will look tomorrow and hopefully I will work out what I am looking for.
Just so that you are aware part of the service I had done included replacement of brake and clutch fluids.
This probably won't make any difference if I have the deterioration you are referring to?
One step forward.............
Thanks again

Kevin

Threesevens
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Re: Gearbox or clutch

Post by Threesevens » Sat Jun 06, 2015 10:52 pm

Also I don't appear to be losing any fluid.

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myatt1972
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Re: Gearbox or clutch

Post by myatt1972 » Sat Jun 06, 2015 11:05 pm

Another thing to try is putting the car into first before selecting reverse and see if it goes into gear cleanly then.
Keith...

Lucky
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Re: Gearbox or clutch

Post by Lucky » Sun Jun 07, 2015 6:55 pm

If the seals are leaking in the master cylinder then fluid can bleed back past them and make the clutch bite very low/gears hard to select. If the problem gets worse the longer you keep the clutch down, I'd suggest this might be the problem, it seems to be a common failure on Mazda master cylinders.

As has been suggested, they're so cheap and quick to swap over there's no compelling reason not to

KiwiDave
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Re: Gearbox or clutch

Post by KiwiDave » Mon Jun 08, 2015 1:01 am

Try selecting fourth gear before reverse and don't rush the process. That seems to work for me. I'm not sure of the process behind the issue but it's the same for previous RX models as well so possibly down to gearbox hydraulics??
1985 Sunrise Red S3 TWR
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Threesevens
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Re: Gearbox or clutch

Post by Threesevens » Mon Jun 08, 2015 9:31 am

Thanks for your comments. I think I will try to replace the master and slave cylinders. I have been on Rockauto but i am not sure which is the right part to order. My car is a 1985 series 3 but I am not sure how this compares to the US vehicles listed. Can anyone suggest the right ones to order as I don't want import them and find they are not right.
I am also going to order front and rear brake hoses and having read some posts on the forum I believe the threads on the hoses are different between series 2 and 3 so I have the same issue on these.
Any help will be appreciated. Hopefully I will become more self sufficient in the future :oops:

codge
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Re: Gearbox or clutch

Post by codge » Mon Jun 08, 2015 11:59 am

Brake hoses.....check out all Nik's threads (by clicking on 'Lucky' in any thread and requesting 'view all posts').
The point is I sent an old sample set of hoses (1985 S3) to Nik and he had someone in the North East make a set to order. The pattern is being kept by the maker for future purchases, so I believe.

Remember you need a 5th hose on our cars. Chassis to back axle line.

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