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1600cc 3 plugs fail all at once
ultrasuede - September 18th, 2016 at 05:04 PM

Hi all,

I was troubleshooting a no start in my engine. I did the timing, valve gaps, different dizzy, different ignition coil. I finally got it to start, but it was only firing on 1 cylinder. I replaced all the plugs, and now she runs like a dream.
What would cause 3 plugs to fail all at once? I was driving the car fine the day before.


AA003 - September 18th, 2016 at 05:26 PM

Crap plugs?


Bizarre - September 18th, 2016 at 05:55 PM

Probably NKG


vw54 - September 18th, 2016 at 07:49 PM

My NKG work great and better heat ranges


Notchbacktastic - September 18th, 2016 at 07:56 PM

Aliens man...


ultrasuede - September 18th, 2016 at 11:14 PM

Bosch plugs fellas, made in Germany. I replaced them with Bosch made in Russia. The gaps are closer on the Russian plugs.


grumble - September 19th, 2016 at 06:26 PM

Quote:
Originally posted by ultrasuede
Bosch plugs fellas, made in Germany. I replaced them with Bosch made in Russia. The gaps are closer on the Russian plugs.


What do you mean the gaps are closer? The gaps are checked and set prior to fitting the new plugs, in almost 50 years I have never seen 3 plugs collapse even in the old days the occasional porcelain used to crack from the heat and fall into the cylinder causing an intermittent miss mostly under load.The thing that would foul 3 plugs is an over rich mixture possibly be caused by a sticking choke ,high float level,leaking needle and seat or the accelerator pump discharge nozzle falling out.


AA003 - September 19th, 2016 at 08:26 PM

I had 3 plugs fail (KLG) back in 1972 after 300kms. One completely and two misfiring. 1303Steve was with me on a trip to Providence Portal. I've also had Champions fail out of the box.


1303Steve - September 19th, 2016 at 08:26 PM

Hi

I do road service for a large motoring organisation, I get called to many late cars with fouled plugs. It usually happens when a modern car is started and turned of too soon or just just incorrect staring technique.

It often happens when a person starts their car, moves it out of the garage, washes it, starts it again and puts the car away, the next start the plugs will be fouled, I've had rotaries that I've had to tow around the block to unfowl plugs as cleaning them has no effect.

Most cars I usually only have to hold my foot flat while cranking to clear the plugs. Some cars I heat the plugs with a butane torch to clean the crap of them.

When the plugs are fowled its usually accompanied by the motor sounding as if it has no compression, this is because the oil has been washed off the bore by flooding.

Steve


vw54 - September 20th, 2016 at 06:37 AM

Quote:

The gaps are closer on the Russian plugs.


the gap should still be 0.025 " or 0.63mm regardless or where the plugs are made