WD40 as starter won't ignite - is it a myth?

[dick6jane]

Here in the troubleshooting section I've read that WD40 should be used as a starter fluid alternative to ether. When I need to, to hasten an airlocked injector pump, I bleed fuel at the airbleed in the filter block, into a squeeze bottle, fed by a supplementary electric pump. One short shot into each port works for a quick start. However, I have never been able to get the motor to fire on WD40. Granted, this is probably a 500,000-mile motor but what's the real skinny? Doesn't WD lack the volatility to be anything other than a myth?

[garysleeman]

Like you I read about WD-40 as being a safe starting fluid sprayed when cranking. On Saturday I made a special trip to the part store and purchased. It didn't work at all. A couple of light shots of starting fluid as the motor was cranking did work. The motor I was starting hadn't been run in years and I had the injector lines off to replace the valve cover gaskets. I tried for hours to get the air out, with the glow plugs and injector lines loose and giving the starter motor plenty of rest between cranking sessions. The faster it turns over the quicker the air gets out.

[Subzilla]

That used to be true but in the last year or 2, WD40 removed the aerosol stuff that caused the ignition (safety & enviroment reason?). I know somebody else could chime in with the more chemically correct explanation.