How often do you change your spark plugs?
- Thread starter LaGrasta
- Start date
Mercury Mike
Famous Member
There's those new 4 point plugs from Bosch. They're supposed to be GREAT! I change mine every time I change my oil, because I love my Mustang. But... the old starter broke my torque converter. =(
Bosch dizzy in 4A Tojo motor, NGK plugs, about 100K kilometres (60K miles). Last couple of times the gap had eroded to nearly 60 thou so I tapped it down to 50 again.
Waste not, want not. The money people expend on unnecessary oil changes, plugs and leads (for example) could be well-spent employing local businesses in worthwhile tasks like rodding out a radiator (as opposed to buying an overseas-made replacement).
Waste not, want not. The money people expend on unnecessary oil changes, plugs and leads (for example) could be well-spent employing local businesses in worthwhile tasks like rodding out a radiator (as opposed to buying an overseas-made replacement).
Mercury Mike
Famous Member
My grandpa has tons and tons of plugs laying around in boxes for some reason or another. Maybe not every oil change... probably every 20k. I change them less frequent in my mom's jelly beans. This is my first and beloved car, so I just....... get paranoid? =) I agree though, Addo.
We're used to 100,000 mile plug intervals these days, but these engines are mostly 50 year old technology and probalby should have more frequent attention. IIRC, the service interval for plugs was a cleaning every 1500 miles and a change every 15,000. I recall points and plugs as a pretty frequent ritual in the old days (pre-1975), as well as the obligatory chassis lube ritual.
With electronic ignition you can probably extend that to 30,000 miles or more because you would have the ability to fire an eroded or fouled gap more easily. Still, the life of a plug in one of our engines will probalby not be able to approach that of a newer design because of oil control, valve seals, combustion chamber design, carb vs. EFI fuel control, and a host of other things.
With electronic ignition you can probably extend that to 30,000 miles or more because you would have the ability to fire an eroded or fouled gap more easily. Still, the life of a plug in one of our engines will probalby not be able to approach that of a newer design because of oil control, valve seals, combustion chamber design, carb vs. EFI fuel control, and a host of other things.
I might be a bad owner. I wait until something starts 'missing' then I check for loose wires, vacuum leaks, dist cap and rotor condition, wire conditions, and finally if I have to pull a plug I just replace them all. I put in Motocraft plugs and at $1.50-$2.00 each it just isnt worth my time to put them back in even if they look good. And if I end up doing any repairs like head work (gaskets, valves, valve stem seals, etc..) I normally figure them in as a 'standard' to be replaced at the same time.
-ron
-ron
66200i6
Famous Member
You get one spark during each collapse of the coil. The spark jumps from sharp edge to sharp edge. With a healthy system you can increase the gape (a discussion we have had here many times) do a search for plug gap.
Each oil change check them until you get an idea of how they are wearing over that 3 to 5K interval. Each time, check the resistance through the plug and make sure the end of the center and side electrode are flat and sharp.
Another thing to check for is that the end of the side electrode is centered over the end of the center electrode. Not just clocked correctly but centered. This configuration provides the same gap from any point on the edge created by the flat of the center electrode to the edge of the flat on the side electrode.
Did I make that confusing? You get one spark during each collapse of the coil. The spark jumps from sharp edge to sharp edge. With a healthy system you can increase the gap (a discussion we have had here many times) do a search for plug gap.
Each oil change check them until you get an idea of how they are wearing over that 3 to 5K interval. Each time, check the resistance through the plug and make sure the end of the center and side electrode are flat and sharp.
Another thing to check for is that the end of the side electrode is centered over the end of the center electrode. This is not just clocked correctly but centered. It is kind of tuff to get this to line up unless you have increased the gap to .05 or greater. This configuration provides the same gap from any point on the edge created by the flat of the center electrode to the edge of the flat on the side electrode.
Did I make that confusing? I need a picture.
Good Luck and keep those edges sharp, Ric.
Each oil change check them until you get an idea of how they are wearing over that 3 to 5K interval. Each time, check the resistance through the plug and make sure the end of the center and side electrode are flat and sharp.
Another thing to check for is that the end of the side electrode is centered over the end of the center electrode. Not just clocked correctly but centered. This configuration provides the same gap from any point on the edge created by the flat of the center electrode to the edge of the flat on the side electrode.
Did I make that confusing? You get one spark during each collapse of the coil. The spark jumps from sharp edge to sharp edge. With a healthy system you can increase the gap (a discussion we have had here many times) do a search for plug gap.
Each oil change check them until you get an idea of how they are wearing over that 3 to 5K interval. Each time, check the resistance through the plug and make sure the end of the center and side electrode are flat and sharp.
Another thing to check for is that the end of the side electrode is centered over the end of the center electrode. This is not just clocked correctly but centered. It is kind of tuff to get this to line up unless you have increased the gap to .05 or greater. This configuration provides the same gap from any point on the edge created by the flat of the center electrode to the edge of the flat on the side electrode.
Did I make that confusing? I need a picture.
Good Luck and keep those edges sharp, Ric.
I have routinely run plugs in air-cooled Volkwagens for 24,000 miles with inspections/re-gapping every 6000 when I filed and re-set the points (which lasted 50K+). Probably could have gone more but even I can be only so cheap. Still have the original plugs in Mama's 98 Trooper at over 100K. Still starts good, runs good, and no loss in performance or mileage.
Joe
Joe
HotRodLarry
Well-known member
I changed the ones in my 200 about three months after I bought it. The only reason I changed them was because the car sat for a year or so, and I threw new plugs in just to get the car running. I bought standard Autolites, they work fine in the car.
I just changed the plugs (all 16 of them) in my 05 Hemi. Im not sure why but they want them changed every 30K. The factory plugs didnt even look like platinums. Its not like its a cheap or base model engine/car. I wonder if its because the Multi Displacemt System? The threads are about 1 1/2" long. Heads are aluminum. The 200 was easier but the hemi design has them through the center of the valve covers so getting to them is not bad. I have not had the 200 long enough to change the plugs more than the first time after getting it running. My 73 cadillac has gone around 30K in 8 years and I have not even looked at them for 3 or 4 years.
Jamie Miles
Well-known member
I clean and check the gap on my plugs every 5,000 and change them every 15,000. I don't run platinums or anything, just standard Motorcrafts or Autolites. My 250 has 217,000 miles on it.
A
Anonymous
Guest
My wife's Sebring recomends changing every 100,000 miles. On my High performance HD i change them every--- well now that i think of it i changed the factory's at 5,000 and have 35,000 on the replacements.
I have an old Hyster fork truck with an air cooled flat head V-4-6volt and i have to change them 2-3 times a year due to not keeping the battery charged well enough which causes them to foul.
Can't find them on my Ford super duty. Darn diesels are so hard to work on!
I'd pop a different one out every oil change and see what it looks like and play it by ear.
I have an old Hyster fork truck with an air cooled flat head V-4-6volt and i have to change them 2-3 times a year due to not keeping the battery charged well enough which causes them to foul.
Can't find them on my Ford super duty. Darn diesels are so hard to work on!
I'd pop a different one out every oil change and see what it looks like and play it by ear.
A
Anonymous
Guest
dont forget that a lot of these 200's and what not arent in the best condition...leaky oil valve stem seals etc...so check them when you change your oil
I am not saying YOURS leaks....just a general note to everyone
I am not saying YOURS leaks....just a general note to everyone
james singleton
Well-known member
Something that MUSTANGSIX mentioned in his post about extending spark plug(s) replacement from 15,000miles to 30,000miles because of the ability of plugs to fire when they are eroded or fouled with electronic ignition. I do not have electronic ignition on my 200 yet! Those of you out there that do have elect. ign., have you found the plugs last any longer because of elect. ign.? With elect. ign. and a stronger spark, and with plugs gapped larger than standard, do plugs seem to last as long, longer, or shorter, than with points and standard gapping of plugs? Just curious. I am planning on installing elect. ign. on my 200. I installed a Petronix ignition on my 73' VW probably 5 or 6 years ago and it was well worth the investment. It seems the plugs have lasted a lot longer; but the big thing was not having to change the points every year, or year and a half!
