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MG Midget and Sprite Technical - Reverse noise

Does the 1500 normally emit a loud grinding noise when entering reverse? I tried reversing it today (moving for the first time) and when the clutch came up it crunched/ground before moving perfectly.
Increasing the revs only made it worse so could the idle (1300rpm) be too high? the sound seemed to eminate from the centre of the remote control.
Thanks Ben
BH Harvey

yes Ben it could the idle at 1,300

allowing for gauge error 1-200 is that your normal fully warmed tickover or is the first idle onthe choke not fully disengaged for some reason?

you didn't have your foot anywhere near the accelorator, not hovering over or "covering"???
N Atkins

That's a pretty brisk idle, and I'd expect reverse to be noisy with the engine at that speed. Mine idles around 900 or so, and while there's a bit of a grunch it's too little to worry about.

-:G:-
Gryf Ketcherside

a few typos before, try this:

yes Ben it could the idle at 1,300

allowing for gauge error of 1-200 then it could be 1,100-1,500

whatever it is, is it at your normal fully warmed tickover or is the (fast) idle on the choke not fully disengaged for some reason?

you didn't have your foot anywhere near the accelorator, not hovering over or "covering"?
N Atkins

Mine seems to be idling high at around 1300 when cold and about 1500 when warm however even at this high idle still goes into reverse as smooth as can be so I don't think the high idle is to blame for this?
C Carter

true, and a lot can depend on clutch wear, hydrolic fluid, gearbox oil, lever, driver technique, gearbox

your indicted 1,500 could really be 1,300, Ben's indicated 1,300 could really be 1,500

a lot of variables to consider and possibilities to be eliminated - due process to be observed and questions answered

and I'm beginning to think my idle isn't as fast as I thought it was
N Atkins

It's idling at 1300 when fully warmed up, at cold the idle is below/around 1000.
I thought that the fault may lie with the idle as reverse has no syncromesh, but I am not sure.
Is the reverse tested during an MOT?
BH Harvey

MOT isn't really about how good your gearbox and engine is

I can't think of that being a fail, give the Tester a look as if it was his fault :)

MOT - one person's opinion at one point of time that the car meet a minimum standard

having the car in good condition and going well . . .

now that's about full and proper servicing, maintanence and repair :)
N Atkins

just thought - after all these years the August 1st registrations still have effect (?)
N Atkins

Is there a syncromesh on reverse gear ?
If thetre is it sounds like the syncro is worn.
S Langston

I don't think any car has a synchro on reverse, as you are (should) always be stopped when engaging reverse there is no need for a synchro. yes?!

Long time no post, been on hol, hope everyone is well!

Cheers,
Malcolm
M Le Chevalier

it's not even on first gear with A-series cars
N Atkins

A bit obvious, I know, but gears (reverse) only crunch if the cogs are still rotating when you select the gear. This happens if the clutch isn't fully disengaging. However even a perfectly adjusted clutch still has a certain amount of drag so the gearbox input shaft is likely to rotate. And if the tickover is set too high then the gears can be rotating quite fast when you go to select the gear. The viscosity of the oil in the box will also have an effect.
Turn the tickover down. If it won't go lower you probably have an induction air leak - very probably via worn butterfly spindles. When selecting reverse pause for a couple of seconds after depressing the clutch to allow things to stop spinning. On the A-series box when starting off always select 2nd gear before then selecting 1st.
Guy

I did put slightly thicker grade oil, in order to give the lever a bit more feel.
And when I had the axle out it was spinning the propshaft in neutral (although I could stop it with my hand).
I'll try leaving it for a few seconds before going into reverse and see if that helps.
BH Harvey

This thread was discussed between 14/07/2011 and 17/07/2011

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