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MG Midget and Sprite Technical - Box or clutch?
|Out of the blue today coincidentally having just passed my mot I've found selecting gear becoming more and more difficult. Selecting first at rest I'm getting a slight graunch and coming down through the box it's taking a couple of goes and a bit of unnecessary violence to get into third and second. Changing up to third also seems stiffer but third to fourth isn't too bad. |
Before I start checking everything anyone got any pointers as where to start. Clutch pressure seems ok but I wonder if it's not fully disengaging?
|Id start with your relationship with god her self 1st ... scarifice 1st born tomarrow (fathers day) if necessary.|
Then id start with looking at your master and slaves hardware and piping ... look for any leaking fluids it just takes a pin prick in the steel line to make life interestig ... and rust can do that easily
im sure everyone is thinking syncros or a worn layshaft .. but i dont think so
what your discribing is to much in to short a time frame ...this is just happening in the last few miles ... for worn syncros a d lay shafts its going to take awile for damage to set in
it could just be that the oil is worn and old and needs changing
or maybe the brake fluid has gotten old and is collecting water and needs replaced
if all the above fails... try some lucas oil treatment in the tranny... about 20% of the trans oil capasity ..not a full oil change out substitute ... that will make things slick and quite agian
|The first thing to check is the biting point of the clutch.|
If it quite near the floor, you could have problem with the hydraulics.
If the clutch operation seems OK, the problem may be the gearbox but, as Prop said, it sounds like too much going wrong in too short a time.
|Dave O'Neill 2|
|Yes biting quite close to the floor. I haven't changed the clutch fluid in years due to an inability to face the hassle of bleeding the bleeding slave cylinder so I guess that maybe should be the first port of call?|
|I think we all share your dread... any idea what a trusted pro would |
Charge ...i bet it cant be that much in comparison to our age and the amount of effort in rehabing we will have to do on the sofa
I really like castrol LMA dot4
I know the spec says once every 2 years... but its been at least 5 years scence ive changed mine and its still clutching along
|Clutch hydraulics would be in the frame. It's easier and cheaper to change the fluid every 2-3 years than fit a new cylinder and bleed from scratch once the cylinder has rusted out from all the water absorbed into the fluid over the years!|
But it might also be:
Collapsed release bearing - usually accompanied by a faint hissing or light scraping when the clutch is depressed.
Worn clevis pin/pushrod/pedal hole at the master cylinder. This situation doesn't develop suddenly of course, but will push a deteriorating situation past the point of no return much sooner. It is of particular importance when fitting a new clutch plate, due to the extra stroke required thanks to the linings springing apart a little when the clutch is released.
|By coincidence I had the same prob on my 1500 a couple of weeks ago.|
I had to leave the car for a week to go to work and when I got back I found the bleed nipple had slackened. I have no idea why - I thought the the slave seal had died.
I just nipped it up again and didn't even need to bleed it, time and gravity had done it for me.
Not suggesting that this is your problem but as I said in another thread it's good to get the simple easy checks done first, so make sure you don't have any slack connectors leaking fluid. It was a surprise to me.
|Matt - what's changing gear like when stationary & engine off, can you run up & down the box easily? Have you checked the oil level?|
|Greybeard- You are a lucky man|
If that was me,well it just doesn't happen like that
Yes. Gearchange seems fine when engine not running which presumably points to hydraulics? Haven't had the chance for a proper look see yet
|sounds more clutch than anything else.|
- check fluid level
- bleed and change fluid if it's old
- check for wear & free play at linkages (clevis pins)
after that it's going to be engine out...
Many thanks. Clutch fluid level looks good but it hasn't been changed for donkeys (well I haven't done it in 9 years of ownership!) so I'll get the "easybleed" out and give that a go as soon as I can find the impetus to face it! I think I read in the archives that its a good idea to fully depress the slave pushrod and wedge it in place whilst running a new lot of fluid through to avoid any airlock in the slave itself?
|yes that's about right. When you're finished bleeding don't forget to top up the master again after releasing the slave rod.|
|The way i do it is simple accurate and easy|
i get a length of clear vinal tubing about 6 feet long that fits snuggle to the bleed nipple on the slave a bread tie or zip tie helps then a crack ope the bleed nipple and in a junk can i just pump out the old using the foot peedle and fill the master when hits half way... pump very slowly to avoid creating bubbles
then just watch the clear hose once your pumping clean fluid then tol off the master and pump the new fluid thur the master and pump until there is no more bubbles in the clear tubing then close the bleed valve and remove the clear tubing into the trash bin and your done
if you get enough tubing you can sit in the car and pump the peddle and not need an assistant
put the trick is... pump slow ...no bubbles is key
Also because that clear flex vynal tubing is so cheap 4 cents a foot ... i dont keep it ... and just toss it... its not worth cleaning up and risking a future project damage
I always start with the easy possible solutions and work my way up.
So, yes, firstly bleed the system thoroughly, ensuring no air whatsoever remains. There are many and varied ways of doing this, but personally I simply attach a length of tight fitting hose from the nipple back to the master to form a circuit as it were, and pump away, tightening the nipple on clutch release as per normal and initially topping up the master to avoid any air ingress.
Failing that, then change the fluid, or at least pump away as before into a jam jar and top up the master accordingly - always remembering not to let in any air!
Failing that, yes, do check out the clevis pin, and also the pivot point of the pedal in the pedal box. For me, the locating hole for the clutch pedal in the thin web of metal on the passenger side of pedal box had worn away, effectively making a bigger hole, thus giving the clutch pedal itself a significant amount of play. Off with the pedal box and pedals - an utter PIA I am afraid - and restored the worn hole in this web for the clutch pedal to the correct smaller diameter by inserting a short length of thin walled tubing. A thin bush as it were... It may be possible though to get something over the pedal spindle and inside this hole without disassembling everything by drifting something in and keeping it in place with a suitable washer - held in place by the nut on the passenger side of the spindle.
Worked for me. Clutch restored and bite point moved upwards significantly.
hope to start investigations this evening!
Just grab hold of the clutch pedal and shake it about a bit first. You will soon see of there is too much play at the locating hole.
|When my clivis pin wore out ... it oblonged the hole and i think i found it because it made alot of popping noise when i pushed it back and forth|
Whereabouts in Aberdeenshire are you? I was brought up in the Granite City myself ye ken!
Fit like? I live about 4 miles NW of Banchory and - like nearly everyone else - work in the oil game. Clearly not great right now, and indeed, like so many others, I am out of a job - hopefully temporarily. So far, 120 000 good jobs lost over this last slump -for which incidentally nobody seems to give a monkeys about...C'est la vie...
If you do push the pushrod back into the slave cylinder, release it very SLOWLY, otherwise you can get air getting past the slave cylinder seal and ruining all the hard work!
Could you get a 2nd person to slowly press the clutch pedal down to return the pushrod to maintain a positive line pressure?
This thread was discussed between 18/06/2016 and 27/06/2016
This thread is from the archive. The Live MG Midget and Sprite Technical BBS is active now.