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Much more frequent plug fouling

925 views 10 replies 3 participants last post by  mhuggler 
#1 ·
Since we've been back on the road, i've noticed a change with another of my cars various "quirks". previously, shes burned a little oil on the dr side 1 and 4 cyls, which would gunk up the plugs every few months, maybe every month and a half. Not a tremendous deal.
Since shes been back on the road, (couple of months) that rate has vastly increased, to maybe every 2 weeks. the plugs coming out dont look nearly as bad, presumably because they havent been in there as long, except one that showed some slight flaking damage on the resistor (knock).
Not sure what to make of it. Nothing has changed as far as the set up, and its always those 2 cyls, change plugs and poof. Could a weak spark maybe be adding to the situation? but if so why arent the plugs as nasty as previously?

I just need to hit the lotto so I can stop "band-aiding" stuff and rebuild it all to spec...or better:grin:

Any thoughts are appreciated,
J

*edit* and FWIW, you can feel it coming on, the engine sounds gradually rougher, and the vibrations, particularly though the shifter change before she actually fouls. this last time, I spotted it a full day before the motor started its shennanigans, and had a socket and spares waiting, but I dont want to make it a habit
 
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#4 ·
been running autolite 25s for a good long while, figured the hotter plugs might help...

If your plugs are being oil fouled then you could try a higher heat range but that might not work. Your plugs are being
splashed with oil which basically insulates them causing them not to fire. They sell plugs that fire in oil if you want to
go that route but It will only get worse. Mostl likely it is a leaky valve seal. It could also be rings but that depends on the mileage
and how the car was driven.
thats the thing, previously they'd have a cake of oil/carbon built up on them, but since its been back on the road, they actually dont look bad, theres a little residue, but nothing really worthy of note on the electrode, maybe a few tiny flecks around the outer ring, and a bit of oil on the threads... thus my confusion. attached are pics of the last 2 i pulled out, sorry for the quality, my camera sucks, lol
as to mileage, were over 200k, and unfortunately she has occasionally been run hard by me, but not in the last few years.

thats the thing I'm sweating, I cant afford major internal repairs right now, and shes currently our only ride.

anyway, thanks for the info folks,
J
 

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#3 ·
If your plugs are being oil fouled then you could try a higher heat range but that might not work. Your plugs are being
splashed with oil which basically insulates them causing them not to fire. They sell plugs that fire in oil if you want to
go that route but It will only get worse. Mostl likely it is a leaky valve seal. It could also be rings but that depends on the mileage
and how the car was driven.
 
#5 ·
Isn't the 25 Autolite what it calls for? Anyway, that's not very hot; you can easily step it up to a 26. If you want to keep running an old Ford to the point where you can't drive it a full day without having to refill the sump(which I've done), what you need are anti-foul caps for the spark plugs. I don't even know if they still make them anymore! :heha:
 
#6 ·
hmmmm. the plugs I got w her iirs shorter/colder but I've had the 25s forever. guess I'll try trading up. and what the hell is a anti foul cap ?cant say I've ever seen one.
Thanks all
J
 
#10 ·
yeah, if I'm getting the correct vibe, I can't imaging that something like that could be good for the motor...lots of added angles and points

J
 
#11 ·
yeah, if I'm getting the correct vibe, I can't imaging that something like that could be good for the motor...lots of added angles and points

J
It's originally just meant to isolate the spark plug from the oil in the cylinder, but in operation it becomes it's own combustion chamber and gets HOT.
 
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