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MG MGB Technical - Steering rack problem

MGB 77 roadster - oilservice and new tie rods - oh dear! I cannot get the locknuts off and would therefore like to take the rods off the rack, however, have discovered that rack does not look like the one in the manual - no lock tabs so how should I proceed?
Here are a couple of pics...any suggestions much appreciated
/Moss


Moss

Another pic...

Moss

Moss,

Does the track rod have an indent punched into the rack at the inboard end of the rod? If so, I have just unscrewed those and the force will overcome the locking indent. I don't remember if MG is built like that, I just remember that some racks are.

Instead of taking it off, have you put a torch (and I don't mean a flashlight) on the lock nut while it is still on the rack?

Charley
C R Huff

Hi CR,no,there is no lock tab with dents - this is the problem. It looks like a sealed unit. It must be possible to loosen but how does one make sure it stays tight again without dents in the locktab.
I have tried penetrating oil and a blue flame on the locknut. Still no movement. Seems rusted solid.
/Moss
Moss

Moss
Hi
I don't know how good a shot you are with a hammer but, to get the locknuts to free up I would get a nice heavy piece of steel or a sledge hammer or similar and hold it nice and squarely under a flat on the locknut and give the opposite flat a good firm tap, turn it a 1/6 of a turn to the next flat and repeat. Work your way around the nut repeating this and it is guaranteed to loosen up.
Good luck Willy
William Revit

Even though I could (eventually) get the nuts to move I couldn't get the track-rod ends off the rods. I used an angle-grinder very carefully to cut along the TRE until I could just see the tips of the threads, but still needed Stilsons on the end of the TRE to peel it open a bit before they would come off. The other one, which had been off before to replace a gaiter and was replaced using copper grease, came undone straight away ...
PaulH Solihull

I never saw a rack with that design of inner ball joint, must be a change or replacement part later than anything I've met. But, unless you are replacing the inner tie rods, I wouldn't touch it. Willy is exactly correct, a solid support and a solid hammer blow on each flat in turn should do it. If not, then slot opposite sides of the nut with a cutoff wheel, even on a Dremel or similar. Cut not quite all the way to the threads, then split the nut with a chisel in the cuts.
And use AntiSeize when putting them back!

FRM
FR Millmore

Thanks all for comments and suggestions. Have since discovered via Moss.com (USA)that the rack is one of the new(but now is very old) sealed types. Very silly idea if you ask me - makes it difficult to renew individual parts. Just changing the rubber gaiters is turning into a real chore. In fact I am renewing the whole front suspension - the PO has not used any form of anti-sieze stuff...anywhere and I exagerate not. Have had to cut almost everything off, wishbones etc. On one side the bolt to the wishbones at the bottom of the stub axle was worn halfway through and the whole was rectangle - Advice: Paint copper grease on the whole unit then do it again at least 8 times!! I never want to do it again (at the moment)...The trial and tribulations of mgb ownership...
/Moss
Moss

I've been lucky in that most things have come off my two cars as they should (even the front eye bolts on the rear springs) but even so I always reassemble with either Waxoyl or Copper grease.
PaulH Solihull

Still having trouble getting the tie-rod locknuts off. Even bought heavy duty pipe 'grips' to help stop the rod rotating whilst I try to turn the locknut off. No help! So going to have to cut them off with a metal cutter. New locknuts now a must have.
Since getting the car last summer, everything I've done has included the use of alot of copper grease...

By way PaulH,have been onto your webiste - excellent stuff, I like the pdf files one can now download
/Moss
Moss

I think I have done something very silly! Advice wanted.
Have put oil in the steering rack then discovered that there is lithium grease already....now I have a suction noise from air and oil mixture when turning the wheel etc. Is this a serious problem or can I stop worrying about?
/Moss
Moss

Was your rack made in Argentina?

I bought my Argentine rack from Moss years ago when they first came out. The price was great.

I found it was packed with grease. At that time there was no technical advice on lubrication of these racks. So I cleaned the grease out as much as I could and added gear oil. I moved the rack back and forth to distribute the oil. Then I flused it out and refilled with SAE 90. I figured I should use what was recommended for the orginal equipment. Oil is a better lubricant than grease if it doesn't leak out. Which so far it hasn't.

I did this by removing the cover.

This rack has held up well and is close to 10 years old. There is no shaft oil/grease seal on my unit. But, I really haven't had any leak issues. Another difference I noticed was the damper that is under the cover is not metal as on the original but nylon. I doubt this rack will give the 30 years plus service of the original. I doubt one can get any replacement parts except the gaiters. So these are likely to have to be replaced as a unit.

So far I haven't had to replace the gaiters. They don't use metal clamps rather nylon "zip ties".

Robert McCoy

If there is too much oil and grease in there it could burst a gaiter I suppose, probably what you are hearing is the air and excess being pumped from one side to the other. Just drain the oil out both sides and it should be fine.
PaulH Solihull

I eventually got the locknuts off, by the way. It took cutting in two halves to just before the thread of the tie-rod and THEN a nut-splitter to losen the nut. Copper grease copper grease copper grease.....

The rack is one of those 'sealed units'. I had the damper and cover off when filling with oil - could not see any lithium grease at that stage. Only when I had put all the bits back on and the new rubber gaters that the squelching began. The new gaters have not split - and yes one has to use the plastic 'zip ties' on the inner tie-rod. As it turns out the unit is not sealed! As the grease/oil (which is now a mushy mixture) is sitting around the innersides of the rubber gaters...I think the idea with this unit is that lithium grease is a heavy non-fluid substance, ie. does not drip. Therefore the rack will not lack lubrication if gaters tear or split. Have also noticed the steering is only 2 and 2/3 lock to lock.

Is this a 'quick rack'? And I do not think it is that old as there is still the label on (on the underside) but worn away

Thanks for the advice/comments...
/Moss
Moss

I think the Mk I MGB's had a quick rack for use with the very large banjo steering wheel. Later racks on rubber bumpers I believe were more turns lock to lock as they had smaller steering wheels.

If I had known that my unit was designed for grease I would not have used oil. Grease is how most modern racks are lubricated. But, so far I have no complaints with the oil I installed.

The old oil filled units had oil in the bottom of the gaiters. It would move around from one side to the other as the car was steered. In fact an alternate way to add lube after the lube fitting was removed was to loosen a small end of a gaiter and use an oil can to top off..

Paul's comment about oil/grease/air making noise is very logical. You may have too much total lube in the unit and combined with higher viscosity you get noise. Mine is quiet.

One more flush maybe or you could regrease it after a good cleaning. The area I worry about getting grease back into the inner tie rod assembly as you couldn't disassemble that.

Let us know how it is when complete.
Robert McCoy

All of the new racks, sold today, are packed with grease and have the quicker turning radius. RAY
rjm RAY

Have now cleaned the rack ( ie. let the oil drain out). Squelching now gone. Probably needs more grease at some stage...so now going to assemble the new front suspension today (day off - hurra, at last I have time to do some work on the mg)
/Moss
Moss

Now everything in place - and all new suspension. It's a lowering kit (about 1,5 inches). But now a new problem - tracking! The steering wheel is now at about 2 'o' clock. Before it was dead centre. No wobble or vibration, or deviation from driving straight.

So could this be the tracking rods or is the symmetry from the setup now out due to everyhting being new? (the old was a real mess - but still drove straight)

Ant suggestions?
/Moss
Moss

The steering wheel can be moved on it's splines once you are happy with the tracking. If you have equal humbers of threads showing on the track rods both sides and the car steers OK with equal lock both sides then I would adjust it to suit.
Stan Best

Really you should position the rack mid-way between its two extremities (it should be the rack stopping the wheels turning in and out any more, not the wheel or tyre hitting something that stops the rack), then fit the steering wheel to the column so that it is in the straight-ahead position. If you then find on the road that the wheel is off-centre when the car is going straight ahead, adjust both track-rods in the TREs - one in and one out - until the wheel is central. Tracking should be corrected before this.
PaulH Solihull

Thanks for comments - Paul what is the difference between tracking and rods? Are the two not connected, ie., adjustment of the rods adjusts the tracking?

Just been out again. Having steering wheel dead centre the car veers to the left. On the original set up the measurement from the locknut to tie-rod end was 32 mm on left-hand side and 28 mm right-hand side (sitting in the car). I did the same. The PO could have adjusted to these measurements to take into account the state of the suspension. Who knows.

So if I adjust left hand side from 32 mm to 28 mm, as on right-hand side, could this correct the problem?
/Moss
Moss

Paul is suggesting you adjust the track rod ends both in the same direction. This keeps the tracking the same and will centre the wheel. You can fine tune this better than moving the wheel on its splines. I always aim to have aprox the same amount of thread showing on both tie rods after the car is tracked. This should put the steering wheel straight, on a car that has been set up properly, as yours soon will be :-)
Stan Best

Hi Stan, I think I understand - if one rod goes in the other has to go out so they follow each other. As the car veers to the left this would mean the left hand tracking rod (as sitting in the car)has to go back towards the rack, and subsequently the right hand tracking rod has to go out pulling the steering mechanism, and thereby the steering wheel, back towards the centre.
That seems pretty straight forward although my next problem is going to be adjusting the rods - The threads beyond the locknuts towards the rack are very worn. It was very difficult getting the locknuts as far they went. I have used new locknuts and copper ease.
/Moss
Moss

It sounds like without buying a new rack you will have to do the best you can with what you have. You may finish up with a car that steers fine, but has unequal turning circles. I think I'm right (if not I will be correctd soon ;-)) that the rack is cut differently along its length so you should minimies any out of centre. Then once you have done this, just put the steering wheel on the best fit spline. When you are driving you are only sensitive to the force on controls anyway, the actual position within limits is ignored.
Stan Best

If the car is veering to one side without you turning the wheel to make it do so, that is something else. It's not the tracking being out that causes this, that will only cause excessive wear to the tyres. It's largely governed by the castor angle of the king-pins, which is the amount the top is tilted towards the back of the car with respect to the bottom. Like the castors on a shopping trolley, this causes the wheels to self-centre when travelling forwards, so you don't have to pull the wheel back after making a turn, or continually make corrections when travelling in a straight line (well, most shopping trolleys anyway). If the car pulls to one side (on a flat and level surface, any road camber will tend to pull the car to the lower side) then the geometry is different between the sides. It's not adjustable on the MGB unless you start fitting shims to the top or bottom links of the king-pin.
PaulH Solihull

Hi Paul and Stan, I used the wrong word - the car is not veering. What I meant is that if I let the car decide - that is just drive in a straight line without correcting the position of the steering wheel to dead centre then the car moves forward in a straight line but the steering wheel is positioned at two 'o' clock. If I correct the wheel back to dead centre from 2 'o' clock whilst driving along then the car turns to the left - as is quite normal when you turn the wheel!
/Moss
Moss

OK, just a matter of centralising the wheel to the rack (if that has not already been done), then adjusting the track-rods to centralise the wheel for straight-ahead.
PaulH Solihull

Have done this - all is good - but now think that it could be fine tuned even more. According to the specifications the front tracking in 4ft and 1 inch. Where is this measured to and from - the inside rims of the wheels or from the centre of the steering rack - thus 2 ft and 0.5 inch either side?
/Moss
Moss

My manual says 4' 1" disc wheels and 4' 1 1/4" wire wheels. Track is the distance from the centre of one wheel to the centre of the other on that axle. Its a chassis design number. Tracking as in this thread is concerned with getting the wheels at the right angle to each other, Usually toe is the only adjustment and it would have been more proper to call this thread adjusting the toe angle.
Delighted to hear your car is steering nicely with the wheel where it should be.
Stan Best

Stan, when you say centre of one wheel to the other where on the wheel do you mean. All basic knowledge I suppose but I have not got a clue - the learning curve for me pt. (present time) is very upwardly steep :)
/Moss
Moss

The middle of the tyre tread , thats why the figure is bigger for the wider wire wheels, hope thats clear.
I suppose its done that way to be similar to wheelbase
The MGB is a nice straightforward well designed car to learn on.
Stan Best

Now I understand! But I suppose this measurement cannot be used to find out if front end runs true?
Moss

Moss -
very confusing, and mostly a matter of terminology, especially the terms "track", "tracking", "track rod".

1) "Track" is the spacing of the wheels side to side. It can be measured from various datum points, but that does not matter since it is fixed in the car construction.

2) "Track" is the path or direction in which something like a wheel or a car travels.

3) "track rod", also "tie rod" acts to control the direction, hence path - (Track sense 2) of a wheel. Since you have one each side, the two wheels are controlled independently, and their [2)"tracks"] might be parallel or not.

4)"toe" is the correct term for the near parallel relationship set by the [3)"track rods"], and can be specified as the angle between the two wheels (good if you have a fancy alignment machine), or as the difference between the [1)"track'] at the front (tire tread surface) of the wheels compared to that at the rear of the same wheels (if you have string or a tape measure). It is commonly called "toe in" because most cars have the front of the wheels slightly closer than the rear; if the specification is positive it is toe in, negative is toe out, or it might be zero or parallel. For MGB it is specified at 1/16-3/32" toe in. That figure was from the beginning of MGB and slightly less is better with radial tires. I use 1/32" toe in as a target.

You can measure toe by setting up some arrangement of blocks and sticks to measure to marks made on the tread surface at the height of the wheel center, Measure at the front, then push the car forward exactly a half turn of the wheels and measure at the rear on the same marks. The difference is the "toe in".

Or, you can use a long straight edge against the wheel, and check that both sides are near parallel to the car body. You want a slight toe in; your straight edge will be about 1/8 per side out at the rear end of the rocker panel. This is generally close enough, and often closer than the alignment shop gets - which is the final option.

Note that any change in the tie rod adjustment will represent about 4x that in toe change. Since the rods are 18TPI, that means one turn is .222" - a bit less than 1/4" change in toe. If your steering wheel is off center, adjust the rods on opposite sides in opposite directions. Always recheck toe after doing any adjustments.

Be accurate - a 1/4" toe error eats tires quickly and makes handling strange.

5)"tracking" is used in UK to denote the adjustment of this near parallelism by screwing the rods in or out. Better called "adjusting toe", or toe in.

6) "tracking" can also refer to the path of the rear wheels with respect to the fronts. If the rear [1)"track"] is the same as the front, then the wheels will run in the same track or path, otherwise the front and rear tracks will be parallel and equal from the car centerline. If the rear axle is bent or not located properly on the springs, the axle will not be square to the car, and the car will go sideways down the road - called "crabbing", and your steering wheel will be off center, assuming it was set when the axle was straight. The front and rear wheel paths will be offset. If you get somebody with a good eye to follow you down the road, this is pretty obvious. Driving straight through a puddle on an otherwise dry pavement will give a visual "printout". You can make a better check by putting a long straightedge against the tire and checking if it is parallel to the side of the car.

FRM
FR Millmore

Ok, understood. Have measured distance between the centre of the front tyres (which measure 185/65-14) - 127.3 cm. So this does not comply to the required 125.1 cm (on wire wheels).However this measurement does not say anything about which side is 'off'. If 125.1 cm is the distance between the front tyres then surely one has to find the centre (lets say on the rack) to be able to measure half of 125.1 - so then 66.55 cm to either side of the centre point. Then the tyres will be parallel to each other - 'true' with correct toe-in and tracking - or have I actually misunderstood?
/Moss
Moss

The track is nothing to do with tracking. As noted above it's unfortunate that here in the UK we describe 2 different things both connected with the wheels with very similar words.
The MGB track is the same front and rear, its a fixed by design number and is only of interest to us as an indicator of the cars character. Wider track more stable higher lateral G more room in the car, but more profilr drag and a wider less wieldy car in tight situations. Its the same for wheelbase.
The front wheels are not parallel, not far off but the small differences are very inportant. They have castor, the king pins slope forwards this give self centreing again fixed by design. Camber, the wheels are angled in or out viewed from the front. This has a big effect on cornering abilty and steering feel and finally toe, how far out of parallel the wheels are viewed from above. On a RWD car they arer set slighty toe in. This means the front of the wheels are slightly closer together than the back when static. This is done so when the car is rolling the loads pull the wheels back slightly and they become almost parallel. Toe out is horrid, as one wheel gets sideways it gets pushed more sideways. FWD cars are set parallel as they pull in power on. All you need to do is set your front wheels toe in to the factory spec, then centre the steering wheel if you like for cosmetic reasons, then enjoy driving it.
Its intersting that your ttack is wider than the data. OE tyres were smaller, but you would expect the bigger circumferance ones to have the same centre,
Stan Best

http://www.ozebiz.com.au/racetech/theory/align.html
If you have a few minutes spare this may be helpful
Stan Best

Thanks for all your comments Stan. I do undertsand now - studied the website, a picture says a thousand words or perhaps a few hundred anyway,... I'll try once again and then I think I'll get it checked by a garage - just to be sure. Shame not to do it right when I have spent alot of time and effort changing all the suspension components.
Thanks again...to all who commented.
/Moss
Moss

I am persistent, I have to find out! If I measure 66.05 cm from the centre of the car to each side then this will be the correct distance of 49.1/4 inches (125.1 cm for wire wheels) between the tyres (centre of the tread)at the front, yes?
/Moss
Moss

Why do do want to know, and how are you going to find the middle of the car to a mm or so? In general terms yes, the middle of the car should be the middle of the track, but there are a whole lot of components with their own tolerances between the two. As long as the front wheels are aligned with the rear so they aren't crabbing, the body could be half an inch or more to one side or other of the notional centre-line, witness the generally smaller gap between the left rear tyre and the arch compared to the right (hornet's-nest duly stirred ...)
PaulH Solihull

1) The specifications state this measurement (if not important then why state measurments - for engineering fun perhaps!?)
2) I am trying to find out the correct set up so the car drives as well as possible.
3) Its interesting.
4) It's an old car, lots of things have not been done for many years.
5) I like getting answers to threads from a huge wealth of knowlwedge on MGB's
6) Thanks for the answer re. measurment from the middle of the car PaulH...

/Moss

Moss

Realised MY problem - I have been concentrating on getting the steering wheel centered instead of the tracking/toe-in and adjusting the steering wheel afterwards...made the very stupid mistake of not thinking about the fact that the steering wheel was more than likely off centre in the first place and most likely more so now as I have replaced all the suspension parts...back to square one....
/Moss
Moss

The track i.e. width between the tyres is a specification, but only in as much as may other things are like 1800cc, 2 doors, wheelbase etc. Toe-in stroke tracking i.e. front wheel alignment is much more important as it affects handling to some extent and especially tyre wear. Toe/tracking is actually set to give zero scrub on the tyres when travelling in a straight line on a flat and level surface, and is what reduces the wear. The toe that this gives is then measured, and given as a specification figure for use with that equipment that needs it. It's affected by many factors including whether the car is front or rear wheel drive, and the rest of the steering and suspension geometry, and is why there will be a huge list of figures for toe depending on the vehicle at an alignment place, but they all give zero scrub.

Yes, get the tracking/toe adjusted correctly first. Then if the steering wheel isn't correct then you will have to adjust the track rods in the track-rod ends to straighten it up, screwing one in and one out according to which way the wheel needs to go, by the same number of turns. However tyre places around here clamp the steering wheel in the straight-ahead position, then use laser gear to adjust the tracking both sides to suit that, i.e. do both jobs in one go.
PaulH Solihull

This thread was discussed between 02/06/2011 and 27/06/2011

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