Smoking engine ?

[rob love]

I meant that the other person would be to crank the engine, or to feel the exhaust for the miss. If I ever had the missus pull the plug wires and get zapped, well, I can't say for sure what would happen. I know it would not be a good thing to laugh at.



My own rule was that whomever's vehicle it was had the job at the sparkplug wires when trying to find a bad plug. When I was in the service, the old 5/4 ton chevs got a new system of shielded plugs and wires. There were a lot of failures early on, and rather than rip out everything and install 8 new wires and insulators, I would have the operator pull each wire one at a time while I felt the exhaust. I was attached to an infantry unit at the time, and some of those guys were pretty tough. But they all said ooookkkkkay the same when a spark plug wire was pulled. I would say OK if I felt a new miss and they would put the wire back in. If I could not quite discern the miss, I woudl say "do it again" and they would pull that wire out again, and say ooookkkkay? I would find the bad wire and unsulator, and have them back on the road (a little worse for wear) within a half hour vs the several hours to tailor the wire set and replace all the insulators in the shields for the plugs.

[Ron Pier]

The screwdriver to earth method is the easiest if there are no plug caps. Otherwise I disconnect all the plug caps and just rest them on the plugs. Then with some insulated pliers, lift each one in turn away from the plug. You can also hear the clicking of the spark which confirms that the lead and ignition is ok, and if the engine note changes when the cap is lifted clear, you can assume that plug is ok. Ron

[Richard Farrant]

Personally, I would approach this in a different way, remove plugs one by one noting if any particular plugs (and cylinders) are oily, this will give a positive indication as to where the problem is.

[Lynn Eades]

In the old days, getting the spark to jump a 1/4" inch gap was your lucky day, and shorting out the plug was no big deal. Any "man" could handle it!
Things have improved a bit and now the spark will jump about 3/4" (for the metric thinking, that may as well be a meter)
The idea of shorting these ignitions out with a screw driver sends a wee shiver (induced current?) up the spine of any life loving mechanic, at the preliminary thought / idea of shorting a plug out, and makes him /her (plus 20 other pronouns) wonder how much truth there is in those warning stickers about the dangers of meddling with these voodoo boxes.
Btw, for the newbies; stick the sharp end of the screwdriver hard to the head (earth point) BEFORE introducing the spark plug lead to the shank. This generates more job satisfaction, for you. If you do it the other way around, it generates job satisfaction for other people.

[RichardT10829]

Hi Barry, you say it’s smoking, is running lumpy too, or does it have a smooth idle but happens to be smoking a whole bunch ?

[carrierbarry]

Yes smooth idle, but lot of smoke.
Took it for a drive yesterday, started on the button. Lot of smoke before and after a mile drive. Seem to run better with a little bit of choke. No obvious loss of power. Fuel is about two years old, but lots and smells ok. Going to give her an oil change and clean filter. What’s the best oil and where to buy in UK.

[Lynn Eades]

Cummins Blue diesel oil because the diesel oil has more zinc that most petrol engine oils. The diesel oil is high detergent and might help to un gum your oil rings (which sounds like the problem to me?)
If not then a mono 30 grade oil high in zinc (important) The zinc has been largely removed from petrol engine oil for "enviromental" reasons.
Do some research to bolster your choice.