Shes starting to sound like a Beatle.

[Gareth]

Hello there!

Just to add a little something to this argument, I fitted Grumpy's top steady a few years ago, and it certainly did what it said on the tin! I don't get so much judder in reverse now, unless I really bring the clutch up too fast!! Heheh

Just one thing, though... I seem to be getting a squeak from somewhere. It's not the suspension. I think... Is it possible that the top steady bushes can squeak 'cos it seems to be different depending on engine revs. I can get it to cry like a mouse if I rev the engine while stationary.

[olonas]

Oops! I duplicated Ray's answer.

[les]

The wire cable connecting the rear of the gearbox to crossmember is quite important in stopping juddering in reverse. It should be tightened to give just slight tension. Whenever I have refitted the head steady, being 'telescopic' it can be lengthened or shortened and therefore made to fit the distance between the two anchor points, with the engine taking up its natural position adjustment can be made, making sure that the engine is not pushed or pulled away from this position, the outside nuts can then be tightened but not overdone, the nuts should be the nyloc type.
Hope all goes well.

[rayofleamington]

Nice one Les,
I thought that all the wire did was prevent the fan hitting the radiator when stopping rapidly.
Well you live and learn....

[56 Splitscreen]

Lads Shes in the new exhaust !! Like a new car !! and thats the truth. To be honest it has taken away a bit of the character ,but Im not complaining. I was beginning to ged headaches not sure were they from fuel emmisions or noise but glad its fixed.
Re the Top Steady this is something I will have to check out ...to see if i have it or not..I do notice juddering in reverse.
Ray ..re the figure 8 ..on mature reflection I think I may not have this symthom so bad ..I tested it the other night and the headlights look regular enough for me.
Is there anything more annoying than a nosiy exhaust !!
At the moment every little imperfection has been fixed
just noticed two little spots of rust though on very bottom of drivers door..

[Willie]

LES, You are mistaken about the gear-box to chassis wire cable.
Its purpose is to stop the engine leaping forward under violent
braking or collision. The fan would puncture the radiator, and the wire
also prevents strain on the clutch operating mechanism which
is mounted between the gearbox and the chassis. It has nothing
to do with preventing judder. As an illustration of its importance
I once left the cable off of an early MGB (same system) and the
result was that if I applied the brakes while going downhill in
3rd gear it would be thrown out of gear by the engine moving
forward. I put it back pretty damn quick!!!
Willie

[olonas]

If it's missing a good replacement from "Grumpy's" is available that utilises two redundant holes next to the right hand damper body (I think this has been mentioned elsewhere). Short bolts and a bracket are supplied. Don't know contact details but adverts usually in Minor and other classic car mags.

[les]

I have heard this one before Willie, about the reason for said cable, but have maintained that the engine and gearbox rubbers would have to be well shot to allow the inch or so movement before hitting the rad, and whenever I have experienced judder in reverse, invariably this cable had broken, with the problem being cured upon renewal. However I can see the point that the cable would make it impossible for any forward movement, and stop mounting rubber strain when braking.
I'm sure I've seen something on this cable in a workshop manuaI, to do with retro fitting to cars without.

[Cam]

The cable in my experience has a LOT to do with the prevention of clutch judder.

My '78 MGBGT started juddering in reverse/1st and when I inspected the gearbox mountings, the cable was slack, so I tightened it and the juddering dissapeared.

ALSO, I have converted my moggy to a Sierra gearbox with a custom made gearbox mounting which does not have the facility for a cable.....the result......clutch judder!!!!

Even though I made my own top engine steady using a piece of 12mm plate welded to the top of the crossmember (under the battery) and this does NOT move!!!

My moggy did not judder at all before the conversion when the cable was present.

In fact at the moment I am thinking of modifying the gearbox mounting I made to incorporate a cable to prevent the judder as it is VERY annoying in traffic jams!!!

I can't speak for everyone, obviously but in my case, the results speak for themselves.


Cam.

[olonas]

Quote from BMC publication AKD530E, workshop manual, Minor.
Engine Steady Cable.
"On models later than car no. 264013 an engine steady cable is fitted between a bracket on the left-hand side of the gearbox rear cover and the rear cross-member to provide longitudinal anchorage for the engine, and adjustment of the cable is by means of a 5/16 in. UNF. nut and locknut."
Engine Tie-Rod.
"To deal with cases of clutch judder an engine tie-rod and bracket assembly, to be fitted between the cylinder head and dash panel, is obtained under Part No. AJA 5054"
If anyone cares to e-mail me I can supply, from the manual the adjustment instuctions for both.
It would appear from this that the cable is to minimise forward movement of engine/gearbox only.

[Cam]

"To deal with cases of clutch judder an engine tie-rod and bracket assembly, to be fitted between the cylinder head and dash panel, is obtained under Part No. AJA 5054"

Yes, if you leave the top engine steady off, then the clutch judder is horrendous. The top steady does prevent most of the juddering.

"On models later than car no. 264013 an engine steady cable is fitted between a bracket on the left-hand side of the gearbox rear cover and the rear cross-member to provide longitudinal anchorage for the engine, and adjustment of the cable is by means of a 5/16 in. UNF. nut and locknut."


With the cable undone there is still slight juddering because the engine / gearbox is not correctly longitudinally anchored at the bottom and can still move (slightly) on the rubbers, even with the top mounting in place.

I have absolutely no doubt at all that the cable will prevent the engine / gearbox from moving forwards under braking and this may have been the main reason for the design, BUT it DOES have an effect on judder, I am speaking from personal experience and it's true.....Honest!!!

I hope that this clears the confusion up.

Cam.

[rayofleamington]

CAM - Re fitting the cable:
I once fixed a Moggie where the gearbox threads were damaged and the cable was therefore loose (only found when the fan hit the rad). The really simple way I found to fix that was to extend the cable by adding a length of M8 bar to it. I then attached the gearbox end of it to the engine/gearbox flange! The M8 is be big enough to replace one of the bottom fasteners so no new hole was needed to attach it. This worked really well and also because it uses the existing hole. The only technical part was to fix the M8 to the end of the cable. (I welded it as that was the quickest way, but if you dig around with different threads, you could probably screw them together)


Well regarding the gearbox to chassis cable / clutch judder I've had a think and here's a theory for you... (sorry for getting technical but some of you may be interested)

During take-up you transmit torque through a slipping clutch. The clutch pedal is on the chassis and the clutch arm is on the gearbox.
As you take up the engine/gearbox assembly will move axially on it's mountings due to inertia and loading effects (and also rotate very slightly due to the reaction of the torque).
This axial movement will actually alter the torque transmitted on the clutch because of the relative movement between the box and the chassis is passed on via the clutch linkage.
The change in clutch torque could help create the cyclic 'judder' as the small clutch opening/closing movement will change the transmitted torque at the clutch and judder the whole gearbox/engine in its mounts. If it's bad enough the judder will cause bigger movements in clutch travel and the whole thing could resonate.

[On 'modern' cars with automated clutch/ gearboxes (like the Selespeed) they look hard at removing any possibility for 'accidental' change in clutch travel to prevent judder.]

The gearbox cable will have a good influence to restrain axial movement of the gearbox, and also keeps the gearbox in place against all the load applied by the clutch pedal (not to mention keeping the fan out of the rad during emergency stops - It can happen

I'd say it has 2 functions, as CAM's experience backs up the possibility of clutch judder!

[Cam]

Cheers for the tip Ray,

I will make up a bracket for the front of my gearbox mounting and attach the cable between it and the engine / gearbox flange. Then hopefully........Judder gone??? Let's hope so!

Your description of the causes of judder make a lot of sense for a normal moggy with a mechanical clutch linkage, but I have a question.

I have a hydraulic clutch and so no movement can be passed on through the clutch linkage from the 'box to the chassis in order to set up the cyclic judder......Hmmm....

Here's a thought, could the fact that the prop is at a slight angle to the 'box be to blame? See what you think:

If the torque transmitted to the prop causes the 'box to move slightly on it's mounting (in the absense of the cable) due to the torque reaction and slight straightening of the prop, this movement would then reduce the torque felt at the clutch, and the small clutch opening/closing movement could then set up the juddering.

What do you think??? or am I in the realms of fantasy again!!!


Cam.

[rayofleamington]

Darn - a hydraulic clutch! That blow's my theory in your case, but it is still a good theory for those of us with normal clutch linkages.
As for other possibilities then, it's probably a combination of engine mass and the mounting siffness, combined with a 'juddery' clutch.

Some clutches judder more than others due to design and materials but they can also be 'glazed' during early running. A new clutch will have high spots so will get very localised heating. Glazing is caused by excessive heat on the surfaces before the lining has bedded in, and the surface properties are damaged causing stick/slip behaviour.
So moral of that story is always to treat a new clutch carefully.

[Willie]

CAM Your 78 MG shouldn't have had a cable as far as I know
After the 4 syncro box was introduced the front engine mounts
were modified to allow about 1/8" movement forwards before
metal to metal contact occurred,preventing any more forward
movement...so the cable was now obsolete. Where am I going
wrong??
Willie

[Willie]

CAM ........... The fact that you have a hydraulic clutch proves
that the steady cable has no effect on clutch judder. The judder
is caused by the action of the engine twisting on its longditudinal
axis ( from nearside to off side). this momentary twist has the
effect of stopping the force applied to the clutch until the engine
whips back the other way....and so on. So they decided to fit
the top steady bar to alleviate it....it is not entirely successful in
reverse!!
Willie

[les]

Your the man Willie, I've just unearthed the passage from the manual that I mentioned in my last post and it does indeed talk of longitudinal anchorage. My apologises to Ray for any misinformation I have given.
Cam seems to have observed the same as myself though with regards to judder, perhaps this cable does both jobs. I thought I'd better get this post in quick before T72 gives me what for! Only kidding T.

[olonas]

Les, I think the piece from the manual is possibly in my post at the end of page 2.
Morris must have fitted the two separate ties for a reason, one for each direction. To minimise fan through radiator and reduce judder. The wording in the manual is quite specific.

[rayofleamington]

Dont' worry Les I don't feel misled. It's interesting to hear people's thoughts and atleast CAM now has a simple idea of where to fit the spare end of the cable onto.
I expect to see piccies on his website if he does that.....

anyway I've been on here lots on account of being stuck inside feeling poorly, but EYGHON23 (aka Gayle) has started complaining so it's log off time for now.
(oops too late - dog house for me now )

[Cam]

Willie: My top engine steady is rock solid and I have observed it when the car is reversing and when revving the engine, it does not allow any lateral movement of the engine.

The engine mounts are new and solidly attached, as is the sierra gearbox mount. So, if fitting a cable is not the answer, any ideas what is?

Maybe fabricating a bottom engine steady? (same as the top)

Your suggestions would be gratefully received.

With regard to the MG, it was a while ago, but I definately remember tightening a threaded bar mounted north-south and under the gearbox rear end. It may have been a solid bar or a cable, I can't quite remember, I'll have to check.

Ray: I'll put the piccies up on the website (when I find an eventual solution) if I can pinch my mates digital camera for a few minutes (proving difficult at the mo!!).


Cam.