Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Classic/Traditional Cars - SteeringRackAdjustment

Well, a successful MOT this morning, but some play in the nearside stub axle, so maybe I was a bit harsh with my criticism last year. I actually witnessed it today.
You may recall a while ago somebody posted a concern about his steering rack twisting under load. I've checked my rack and under load the centre bracket onto which the trackrods are located does move upwards..................slightly.
Anyway, my rack had the tiniest amount of free play so I set to work to understand the adjuster. These things are quite simple. Where the rack passes over the pinion, it is held in place with a spring tensioned plunger. The tension is adjustable and often this is with a shim or two under the bolt head. Taking a shim out increases the tension. But the Morgan turned out to be different. Access is tight without disassembly...........


The only spanner which will fit that nut while in place is an open ender, and I had to buy one specially........
Because it's BIG. An inch and a half actually.


The nut is retained by a star lockwasher with tabs which are bent over - more on this later.


After using a screwdriver to lift the tabs, it unscrews easily, but is quite stiff........
Visible is the rack. It looked a bit dry so I added a small amount of 90 grade diff oil, and some grease. The centre gold strip is a square section which mates with the plunger.


Here's the nut........

It comprises five parts - the outer nut acts as an adjuster/locknut. The inner part is the main plunger which is threaded to the locknut, and uses the same thread to locate in the rack housing. This thread is very fine.

And here are the other two components..........
A spring which is roughly finished and bears file witness marks on each end. Rust was evident on the surface, so I cleaned it up and coated it in grease. The actual working part of the plunger is the black part which is a sort of nylon, and sits over the rack...........the slot which mates with the square section on the rack is just visible. You can also see the rusty scale on the star washer, which is almost impossible to remove, because the washer is peened into the adjuster.


So, this is what you do......
The adjuster needs a 7/8 open ender.....


First you must straighten the star washer tabs to allow the centre bolt to turn. Next slacken off the locknut. Then the centre bolt/plunger can be tightened using the 7/8 open ender but only a small amount at a time. Retighten and the job is done. The alternative is to do as I did and remove the whole thing. But be warned............. To refit the plunger you must compress that spring a small amount in order to engage the threads, which needs two hands. In the end I removed the wheel but even then it was a real struggle.
Here it is back in place.

If you compare this photo to the third photo above, you can see that the locknut is 1/16th of a turn further round. I marked the relative position of the plunger and locknut and added maybe 1/32 of a turn, so the relative position now is a shade tighter, and that has removed the tiny amount of free play at the steering wheel.


If you chose to meddle with this, make sure you mark the original position, or take photos, so you may restore the original setting if it doesn't work.

A superb piece of investigation Dave, my car has it's 1st MOT in September. Your information could be invaluable then. Is there a user test that can be done to see if there is problem.

Just wobble the steering wheel side to side Dave. Small movements each way and watch the front wheel for movement. If you want to check the vertical movement on the centre of the rack. you can twist the steering column with the offside bonnet up, and see what happens. It shouldn't be a problem with cars as new as ours, and the tester didn't bother about it. Apparently new/young testers are being told to make allowances for 'the life/age of components', and accept that things wear over time - eg kingpin bushes. The wear on my nearside is clear, and disappointing given the mileage is still under 10k. But looking on the bright side, it means that I can justify some hard chrome kingpins, and a Mulfab roller bearing conversion over winter, which will make a really good thread.

I only resolved to look at the rack adjustment because I don't like things that are not 'right'..... but I had to wait for the spanner to arrive. It seemed worse when the engine was hot, so thermal expansion of the rack housing may have played a part.

As a postscript, I'm just back from a 168mile tour round Derbyshire - Glossop - Buxton - Ashbourne - Denby - then home via Ollerton using B roads where possible. MrsW navigating.
As a result of the adjustment and lubrication, the steering is noticeably sweeter, and lighter. The difference is obvious. We left at 0700 so had the roads to ourselves for a couple of hours. Saw a gaggle of Caterhams, an odd MX5, and MGB, the obligatory Blonde in a white Merc SLK - but little else. Lots of Motorbikes.
An excellent run out and just over half a tank still showing on the fuel gauge.

Good run that Dave (the bits I know!).
SWMBO & I can recommend Chimes Cafe in Ashbourne for a good cuppa (plus the cheese omelette and cheese/ham panini were excellent). You might also find a timepiece to interest you - didn't have space for a grandfather clock though!!
Cheers,

A Great Thread again Dave.
Bikers - used to be a very large Sunday casual meet at the Bike shop in Matlock Bath, drawing them in from miles around. That was some years ago now.

That meet still goes on - hundreds congregate and on a warm Sunday it's quite a spectacle.

Dave,
things might have changed since I biked there last a few years ago, but do I recall that the Cat 'n Fiddle was the big attraction roadwise in that area?
regards,
G

The C&F is still a bike magnet, and the Police use helicopter speed checks, also on the A6, and probably elsewhere.
I was last on the C&F two years ago on a misty & wet busy Saturday en route to a wedding. Not a pleasant run. Too many HGV's on the road.
Matlock Bath is the place to meet it seems. They line up each side of the road, and fill the bars etc etc. Especially on sunny days.

Post Photobucket reboot from May 2010:

Well, a successful MOT this morning, but some play in the nearside stub axle, so maybe I was a bit harsh with my criticism last year. I actually witnessed it today.
You may recall a while ago somebody posted a concern about his steering rack twisting under load. I've checked my rack and under load the centre bracket onto which the trackrods are located does move upwards..................slightly.
Anyway, my rack had the tiniest amount of free play so I set to work to understand the adjuster. These things are quite simple. Where the rack passes over the pinion, it is held in place with a spring tensioned plunger. The tension is adjustable and often this is with a shim or two under the bolt head. Taking a shim out increases the tension. But the Morgan turned out to be different. Access is tight without disassembly...........



The only spanner which will fit that nut while in place is an open ender, and I had to buy one specially........
Because it's BIG. An inch and a half actually.



The nut is retained by a star lockwasher with tabs which are bent over - more on this later.



After using a screwdriver to lift the tabs, it unscrews easily, but is quite stiff........
Visible is the rack. It looked a bit dry so I added a small amount of 90 grade diff oil, and some grease. The centre gold strip is a square section which mates with the plunger.



Here's the nut........

It comprises five parts - the outer nut acts as an adjuster/locknut. The inner part is the main plunger which is threaded to the locknut, and uses the same thread to locate in the rack housing. This thread is very fine.



And here are the other two components..........
A spring which is roughly finished and bears file witness marks on each end. Rust was evident on the surface, so I cleaned it up and coated it in grease. The actual working part of the plunger is the black part which is a sort of nylon, and sits over the rack...........the slot which mates with the square section on the rack is just visible. You can also see the rusty scale on the star washer, which is almost impossible to remove, because the washer is peened into the adjuster.



So, this is what you do......
The adjuster needs a 7/8 open ender.....



First you must straighten the star washer tabs to allow the centre bolt to turn. Next slacken off the locknut. Then the centre bolt/plunger can be tightened using the 7/8 open ender but only a small amount at a time. Retighten and the job is done. The alternative is to do as I did and remove the whole thing. But be warned............. To refit the plunger you must compress that spring a small amount in order to engage the threads, which needs two hands. In the end I removed the wheel but even then it was a real struggle.
Here it is back in place.



If you compare this photo to the third photo above, you can see that the locknut is 1/16th of a turn further round. I marked the relative position of the plunger and locknut and added maybe 1/32 of a turn, so the relative position now is a shade tighter, and that has removed the tiny amount of free play at the steering wheel.



If you chose to meddle with this, make sure you mark the original position, or take photos, so you may restore the original setting if it doesn't work.