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Practical Classics (UK) - - CONTENTS - Prac­ti­cal Clas­sics.

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QMy Volvo 144 has quite heavy steer­ing. I thought this was a char­ac­ter­is­tic of the car, but then I drove a friend’s 144 and found its steer­ing won­der­fully light. It’s fit­ted with cor­rect 165 R15 tyres. I’m go­ing to take it off the road over the win­ter for an over­haul. What might be wrong with it?

Robin Stokes, Am­s­ter­dam

AThere are a large num­ber of pos­si­ble causes. We’ll take a gen­eral look at all of them. Old, bald­ing or in­cor­rect tyres can make for heavy steer­ing – and cor­rect pres­sures are im­por­tant, too. Note that ra­di­als are usu­ally in­flated by about 3-5psi more than cross­plies. Be­ware of over-in­flat­ing tyres for lighter steer­ing, as this will lead to a loss of grip. Don’t ever ex­ceed the fig­ure given for high­speed cruis­ing in your man­ual.

Next, ex­am­ine the steer­ing. Start by re­mov­ing the steer­ing rods com­pletely. Ex­am­ine them for split rub­ber boots, water ingress and rusty sludge where grease should be. All balljoints should be stiff and tight, but should move smoothly. See how easy it is to swivel the hubs while in the air. If th­ese are stiff, look at the sus­pen­sion swivel joints, balljoints or king­pins.

Check the steer­ing box oil and make sure you can move its Pit­man arm smoothly from lockto-lock. You should feel very slight tight­ness when the arm passes its dead-cen­tre po­si­tion. There should be no play in this po­si­tion, but play will in­crease ei­ther side of the cen­tre.

On the other side, give the idler a rare bit of at­ten­tion. Re­lease the top nut and push the shaft out. In­spect for cor­ro­sion and worn bushes. Clean, lu­bri­cate and re­assem­ble. Set the top nut with just enough ten­sion that the idler’s Pit­man arm can just be moved with light pres­sure from one fin­ger. Make sure the steer­ing wheel moves freely. On older cars with rigid steer­ing columns, the col­umn must be in per­fect align­ment with the steer­ing box. You can shift the bracket that holds the col­umn un­der the dash. If there’s no ad­just­ment left, then fit a shim un­der the steer­ing box to an­gle it slightly. A mil­lime­tre at the box will trans­late to 5mm or more at the top of the col­umn.

Re­assem­ble and set the toein (or ‘track­ing’). We rec­om­mend in­vest­ing in a DIY track­ing gauge and do­ing this your­self. If ev­ery­thing’s mov­ing freely and the track­ing is

cor­rect, you should find that the steer­ing self-cen­tres well at higher speeds and doesn’t need con­stant cor­rec­tion. It should hold a straight line over rough sur­faces, too.

If the steer­ing be­comes heavy when en­ter­ing a sharp bend at speed and seems to weight up the more you turn in, this re­lates to the cam­ber and cas­tor of the front sus­pen­sion. Start by look­ing for bent arms and poor ac­ci­dent re­pairs. Re­place worn-out bushes, which will al­low the ge­om­e­try to al­ter as they sag. Cas­tor and cam­ber are not ad­justable on some cars, so it’s likely to be broadly cor­rect. If they are ad­justable, they may have been badly set-up in the first place or fid­dled around with since. In the case of your Volvo, they are ad­justable by adding or re­mov­ing shims at the up­per wish­bone mounts. We showed you how to mea­sure cas­tor and cam­ber in the Au­gust 2018 is­sue of

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