Killing your engine with Redex

Redex
Originally uploaded by Phil_Parker

Owning old vehicles I've always been a big fan of Redex petrol additive. It really does make an engine run smoother and keep all the important pipeage clean. I don't do that many miles but every so often I like to treat my VW campervan to a slug (sorry, carefully measured dose) of treatment.

So it was I dosed the fuel on Wednesday morning. 20 minutes later I hopped in to head off the the boat club. The engine fired and then died. Further attempts had it turning over but not firing at all. B&**$r I thought and went around the back to have a poke at the engine.

The fuel filter looked dark so I changed it over, something I got really good at when suffering a rusty fuel tank a few years ago. This didn't help but I noticed that the petrol appeared purple and not the traditional clear. I didn't think muck of this at the time putting it down to a trick of the light or dirt in the filter.

Since changing the filter had splashed a small amount of fuel over the engine I decided against checking for a spark with a spare plug. If I found one I'd have no eyebrows left ! A car was borrow for the trip to the club while I pondered the issue.

Driving through the countryside the problem seemed very similar to the time I filled up with water from evil Sainsburys. The purple petrol was the clue. I had filled up a few days earlier, perhaps I had a tank of water or even red diesel.

Back at home plan A was to try and prove the electrics worked. I still couldn't do the test with the spark plug on the engine block - you can't see the spark when sitting 14 feet away working the controls in the front. However I reasoned that if I sprayed some carb cleaner in the top, if there was a spark, this would ignite and prove something. You can actually run a car on carb cleaner spray instead of petrol, it's just not economic or convenient as you have to spray it in the top of the engine every 20 feet or so...

My carb cleaner can was empty but undeterred I decided to use WD40 instead as that's nearly as inflammable and every classic car owner has a can in the glove box. A quick blast in the carb followed by a run to the driver seat and I proved my point. The engine fired, not for long but it fired. A longer squirt and we fired again followed by a little bit of coughing and chugging and then the engine roared to life.

So I think this is the problem - that Redex had sunk to the bottom of the petrol tank. Had I left it longer the treatment would doubtless disperse through the fuel. Better still if I treated it at the petrol station, the vibrations while driving would have mixed the two. I'll try and remember to do this next time.