Changing Front Shock
Absorbers and Springs
I bought my shock absorbers from Ashley Banks Ltd, LANGTOFT, near Peterborough but this
firm seems to have gone out of business.
I understand (5/8/2009) that the Routemaster
Association knows where front and rear shock absorbers may be obtained.
This guide has been produced
using the very considerable skill and experience of Colin Springall and is
based on work carried out on RM471 on 10th April 2005. It took about† two hours to replace each shock absorber
Routemasters are big heavy
vehicles and great care needs to be taken with the health and safety
precautions necessary when carrying out maintenance of the suspension.
- Choose a safe
location with an inspection pit and adequate lighting. Apply the
handbrake, chock the wheels and jack up the front of the bus.
- Position an
adequate body support stand in the pin located under the body behind the
front wheel arch
- Continue to
jack up the front wheel until it can be removed
- Remove the
- Find the two
bolts that secure the shock absorber to the top of the suspension unit and
remove them. You may have to gently
ease the brake pipe away from above the bolt to get a good purchase on the
head of the bolt.
- Locate the
eight nuts on the lower base plate of the suspension unit. Spray them with
- Loosen the
nuts and remove six of them completely.
- Use the jack
to keep the base plate in place and remove the last two nuts
lower the jack and the base plate, spring and shock absorber can be
- Undo the nut
securing the shock absorber to plate at the top of the spring
- Remove rubber
bushes and top plate
- Remove the
- Place the
base plate and shock absorber in a vice and undo the four bolts securing
the shock absorber to the base plate
clean the top and base plates. Check
for cracks around the central area.
- Secure the
new shock absorber to the base plate. Donít
over tighten as you may break the securing caps.
wire the nuts.
- Place one of
the rubber bushes on the top of the shock absorber and carefully locate
- Place the top
plate in position, then the other rubber bush and secure with the large
washer and nut at the top.
- Using the
jack, carefully position the shock absorber and spring in place. Rotate
until the holes in the top plate line up with the holes in the top of the
upper part of the suspension. Insert two of the LONG bolts from the base
plate temporarily to hold the shock absorber and spring in place. Do not
step 7 above secure the base plate with the remaining six long bolts, then
remove the jack and retrieve the two long bolts temporarily securing the
top plate and transfer them to the base plate. Place the two short bolts in
the top of the unit and check that all the bolts are tight.
- Replace the
wheel, jack the bus up and remove the body support stand.
- Repeat steps
1 to 22 on the other side of the bus.
The old shock absorbers on RM
471 were completely worn out and the offside spring turned out to be broken.
Following the replacement of the shock absorbers and spring the vehicle felt
completely different. The ride was very much smoother and the nine big bounces
after going over a raised zebra crossing were reduced to one. The steering was
lighter but more positive with less play. At speeds of over 35 mph there was a
lot of vibration and now there is none. Anybody experiencing these sorts of
problems with their bus should seriously consider replacing the front shock
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