The Classic MotorCycle – September 2019

Anyformofreforming damaged parts, whether

panel beating or as here, involvesa‘gently,

gently’ approach with manylight pressing

or beating actions and no heavy-handed big

thumps. With the taper applied, gentle, true

vertical taps withahammer will press the

tapered former into the opening to reform

its shape. It is possible to achieve the same

result usingavice, but, again, verygently; or

as we have the mandrel press, the brass taper

bosswasreformed with manylight, sharp

pressing actions.

It is possible to split damaged bosses, which

will wreck the item or makerepair harder.If

this isaworry,screwanut of appropriate

thread onto the boss, but in this case the

bosswasexternally misshapen too, so this

wasn’tpossible.

After cleaning paste

debris, the external

thread is cleaned

with an appropriate

die. With petrol pipe

fitted and tightened

in place, thefloat

bowl is refitted to

the carburettor.Then

check for leaks,

which can often be

resolvedby further

lapping in.

Turn asmall former with taper to match thefloat bowl petrol pipe
mounting from ½in mild steel rod.Yes, Iknow some won’thavealathe,
and in 1978 neither did I, so the taper formerwasmade by mounting a
shortlength of rod (cut down fromabolt) in an electric drill set atalow
speed and afile. Took some time (all morning in fact) and although it is
not an approach to recommend on safety grounds, it works.

With shape almost restored, the jobwasfinishedby grinding the taper

face with the former using valve seat gaining paste. This can be done

manually or withadrill at slow speed. If you have one,abench drill is

best option but, if not,acheap, variable speed hand-drill will work.

bench drill free.Autojumblebuys included

aweightymandrel (rack) pressfor £35,valve

seat grindingequipment, includingmany

new wheels (£200) andvalvegrindingtool

for £120. Andahugebox of puller sand

associate dtools –some of whichwe haven’t

aclue what role theyserve –werebought

for ameasl y£20 from an elderly friend

whowanted to declutter hisworkshop and

they’ve been brilliant.

Luckily, I’ve hadlotsofspannersand other

hand tools since childhood whenI‘nicked’

them from dad who often left themoutfor

me to take, and thenext generation has

THE CLASSICMOTORCYCLE|SEPTEMBER 2019 93

Classics

ife