MICK’S TIPS
TEMPERATURES RISING IS A GOOD THING
ARE YOU still managing to get your old toy out for t he occasiona l drive? I hope so and, t his time of year – particula rly if you live down south – you need to be a bit patient. While your modern car can live with being started and driven of f (gent ly) more or less instant ly, t he old girl won’t cope so well. So get up a few minutes earlier.
That’s because t he technolog y is ver y dif ferent. Old engines run bigger clea ra nces, dif ferent lubricants and just need more patience. Even t he f uel systems are different and need time.
Since we’re at t he top of t he motor, let’s ta lk about t hat. In a cold engine, what tends to happen is t he f uel gets vaporised through t he carburettor but can condense again as it hits t he cold metal in t he inlet tract. So t he engine, which is a lready running rich at t his stage isn’t going to be happy and there will be a tendency to foul plugs unless you give it a chance to get up to temp, before you make demands.
The same thing applies to ver y early f uel injected cars out of t he si xties and seventies – t hey need time to get up to speed.
And, wit h a ll of t he above, once you start you need to let t he engine get some temperature before you shut it down again. So no f iring it up just to move it out of your way and switch it of f. Again, it fouls t he plugs and, in extreme cases, you’ll end up wit h a non-sta rter.
Letting it warm up is a lso critica l for t he depths of t he engine – crankshaft, pistons, cams and so on. Older designs run t he prev iously mentioned big clearances, so t he oil and t he components need both heat and time. Remember oil isn’t just t here to lubricate : it’s t here to ef fect ively ta ke t he ‘k nock’ out of an engine by ta k ing up clea ra nces, assist in temperature control and lubricate. Which is why a modern car oil in an old engine (and v ice-versa) is often a bad idea.
That extends a ll t he way back to the gearbox in some cars. We’ve come across models where the sy nchro won’t willingly co-operate until you’ve got some heat back t here too.
How long should you warm it up for? You don’t have to sit around till lunch time but a few minutes is a good sta rt. As a r ule of t humb, if you can get it off the choke and have a reliable id le, you’re about right to go. Even t hen, you need to be gent le for t he f irst few miles until you see t he temp gauge swing into its normal range.
It might seem like a nuisance, but you can walk back into the house and f inish your cup of tea while t he old girl gets up to speed. Think of a ll t he money you’ll be sav ing by not rushing into t hings, fouling t he plugs, and prematurely wearing out your engine ! Note: MickrunsGlenlyon MotorsinBrunswick,Vic. Tel(03)93805082.