Part 2 - Drive Chain Replacement
By Mike "IRONMAN" North (ubrew@webhart.net)This is the second in the series of articles I jotted down while helping out at one of Her Majesty’s establishments. Thanks are due to the dragon (her indoors) for posting bail.
At first sight this seems like an impossible job - the chain is attached to the engine and goes round the axle- but I’ll take you through it step by step.
You’ll need the basic tools of course and as usual we’ll start with the ¾ combination wrench to open the Guinness. Just a note here, ‘girlie’ NASCAR mechanics may want to substitute a Bud - Guinness may be a little strong for you.
First you have to remove the engine flywheel. Start by taking off the cover and the large flywheel bolt. This is usually very tight but gentle application of the oxy acetylene cutter normally does the trick.. All the books and manuals recommend using a puller to remove the flywheel, but I’ve found a much easier way. Just take a 3 pound lump hammer and strike the flywheel several times sharply on the edge. This will generate a crack large enough to allow it to be removed. Be ready to catch the pieces. Now, using the lump hammer, strike the crankshaft as hard as you can. This will move the whole crankshaft over enough to allow the chain to slide off. Phew, really ready for that Guinness now.
OK, now you’ve removed the chain from the engine you just have to get it off the axle. This is not difficult - just remove the axle. Start by loosening the bolts holding the bearings, I find a digital vernier caliper is useful here to position under the bolt head and lever it out. Now use the lump hammer and your trusty scrim bar to drive out the axle, slip off the old chain and replace with a new one. Don’t worry if the axle is slightly bent during this process - this is another old chassis tuners trick to increase grip on banked curves. Short anecdote here - a fellow racer bent his axle in last year’s enduro, but he continued on round the track kangaroo fashion. I think he may have won the event but he said he had to leave early as his library books were overdue.
Anyway, reassembly is the reverse of the above, except don’t forget you can use some of the left over bolts etc. to repair that old watch in your kitchen drawer.
Next time I’ll teach you how to drastically reduce your motoring costs using just an empty gas can, siphon tube and your neighbour’s K car.