Inspect and service your distributor

An easy job that can have a huge effect on engine performance

The distributor triggers up to several hundred sparks per second. The importance of doing this with pinpoint accuracy can’t be overstated. A distributor that’s slightly awry will throw the whole engine out-of-kilter, leading to rough running, a lack of performance and unseemly lurching when stepping on or releasing the throttle.

Specialist equipment is needed to fully analyse a distributor’s performance, but you can make a pretty decent job at home by checking a few basic items for wear, play or breakage. Quite often, a simple freeing-off and oiling session will restore perfect function.

It’s not necessary to strip your distributor on a regular basis, but it’s worth a one-off inspection if you’ve hitherto left it to fend for itself. It’s also a wise preliminary step to fitting electronic ignition. Not only should you make sure everything’s right before you install it – but you’ll be poking about inside the distributor a lot less often afterwards, so a good check-up and oiling session will see it right for a long time.

If you find the main shaft has a lot of side-to-side play, the distributor will need replacement or rebushing. Anything else should be replaceable. It may be possible to cannibalise another unit. Be careful if swapping centrifugal advance springs and vacuum capsules between units, though, as they’re often tailored to specific engines.

Make sure the cap and rotor arm are clean and not cracked or burned. Also check the ends of the HT leads and the sockets on the cap are making a good connection. Rough running can sometimes be down to the coil. This is rare, though, so beg or borrow a substitute before buying another.