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MG MGF Technical - Tight gear change

Does anyone have an opinion on the gear shift problem I am experiencing.

It can sometimes be extremely difficult to push the stick into first. best way to describe it is that its a bit like a fat person squeezing through a door, keep the pressure on for a second or so and it "pops" through.

With the engine off the changes seem smooth.
Engine on and car stationary the characteristics above (keep pressure on and it pops in) seem to apply to all gears.

problem most prominent in first & second when driving.

seems slightly worse when engine (clutch?) warm

tightening the nuts at the base of the gearstick improved things slightly (odd?)

if it really doesnt want to go in (maybe 1 time in 20) releasing and then depressing the clutch again usually means it will go in more easily.

I jumped to the conclusion that it was a dragging clutch and tried toasting it out (handbrake on, 3000 revs in 4th gear until i got smoke out of the back. Thought i might have overdone it actually so a bit reluctant to repeat the excercise as it only made things slightly better.

any ideas?
cheers,
james
J LEWIS

It sounds like either the clutch is not doing its thing properly or the gear syncros aren't. Have you checked the gearbox oil level recently or the clutch fluid? You may have a leak somewhere or the release arm is too stiff and needs some lubrication.
Tony

Thanks Tony. Clutch fluid was the first thing checked and OKed (presuming its the small tank you can see through the cutout section of the front bulkhead cover with a white cap? - couldnt see a max and min mark but was filled to 1.5 cm from the top and above the level of the internal baffle? (which i presumed marks the min level)

I thought the fact that gearchanges are straightforward with the engine off would eliminate both the gear change mechanism and the gearbox (and GBoil) itself - am I wrong about this?

Dont think its Synchros as third gear is unaffected (only really 1 and lesser extent 2 while driving)

would a stiff release arm not manifest itself through the pedal being hard to press or sticking. That said I've got nothing against giving it a bit of a lube - does anyone have photos of where and how?

Oh, and 1 other "feature"... after noting something in the archives tried going for second then sliding into first (keeping clutch depressed throughout)in the occasions it refuses to go into 1. This works every time. In fact its a good enough workaround for me to live with if clutch replacement is the alternative...

thanks,
James
J LEWIS

The fact that snicking 2nd then into 1st makes it easier points to the syncros not doing their job - it is most obvious in the lower gears as the differences in revs between the wheels and engine are the most extreme. I would check the gearbox oil level first as some have been found to be low from new - in fact a change is probably a good idea anyway if the car is a few years old, it can work wonders! You could also learn to double declutch, one of my first cars had no syncro on first and you soon learn to do this!
Tony

I still don't understand why gearbox oil would make a difference to a gear shift which is fine when engine is off... can anyone explain? - I suppose increasing the drag in the gearbox (more viscous oil?)might help slow things down if the synchros are tatered... would this help getting first from neutral while stationary though?

Not that I have anything against changing the oil...

So you think its Synchros then Tony rather than the clutch drag associated with the PG1
J LEWIS

I don't know how much you know about syncros so bear with me...the syncros speed the actual physical gearcog you are trying to get up to the required revs for a smooth meshing of teeth with another gearcog to occur. With the engine off there is no speed differential at all between the input and output of the gearbox so any gear can be selected resonably easily. Once motion is added by either the engine or wheels differences will occur in the box and the syncros will "syncronize" the 2 gears to be meshed. If this doesn't happen you get a crunch of teeth or that fat person through a door feeling(great imagery BTW!)If the clutch isn't slipping at all in the higher gears I would still try the cheapest option of checking/replacing the oil. Low oil or poor lubrication will effect the syncros performance. How many miles has it done and do you know it's history? Is it a "city" car that has spent all it's life in traffic? It could be that the clutch isn't disengaging enough for the low speed syncros to cope, at higher speeds and gears there is always less speed differential to adjust- I'm sure you have seen the other thread called "no gears" so those checks are worth ago as well.

Snicking 2nd then first uses the 2nd gear syncro to spin the internals up to speed rather than 1st's.
Tony

Thanks Tony, lucid explanation, I might just check my oil tomorrow!
C.R.B. Simeon

This thread was discussed between 04/09/2006 and 06/09/2006

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