|
Sponsored Links (Register now to hide all advertisements) |
|
|
Thread Tools | Display Modes |
05-12-2024, 05:38 PM | #1 |
Senior Member
Join Date: Sep 2016
Location: Roanoke, VA USA
Posts: 1,955
|
How many miles should spark plugs last?
I’ve cleaned the plugs in our car every 3-4 thousand miles or so. However, we’re still running the same plugs that came with car. So, that’s about 16,000 miles in a little less than 5 years. (I have no idea how many miles were on the plugs before we bought the car.) The car recently developed a miss under load, and cleaning the spark plugs this time did not help much.
How many miles should a set of spark plugs last? Sent from my iPhone using Tapatalk |
05-12-2024, 08:13 PM | #2 |
Member
Join Date: Feb 2023
Posts: 90
|
Re: How many miles should spark plugs last?
Ihave been driving a's 65 years I have never bought a new 'plug. Decide which one is missing through it away. get another used one.
|
Sponsored Links (Register now to hide all advertisements) |
|
05-12-2024, 08:19 PM | #3 |
Senior Member
Join Date: Jun 2014
Location: Melbourne, Australia
Posts: 7,564
|
Re: How many miles should spark plugs last?
How certain are you that a plug is causing the miss? There are a number of other possibilities worth investigating.
__________________
I'm part of the only ever generation with an analogue childhood and a digital adulthood. |
05-12-2024, 08:37 PM | #4 |
Senior Member
Join Date: May 2010
Location: Oregon
Posts: 6,011
|
Re: How many miles should spark plugs last?
When the electrode is burnt away so it can't be gapped, it is time for a new plug.
|
05-12-2024, 08:49 PM | #5 | |
Senior Member
Join Date: Sep 2016
Location: Roanoke, VA USA
Posts: 1,955
|
Re: How many miles should spark plugs last?
Quote:
Good question… This is what I’ve tried. - Swapped out coil with known good coil; still no power under load - Swapped out condenser with known good condenser; still no power under load - There is no carbon tracking on the distributor body - The rotor button looks okay - The distributor cap looks okay - The high tension coil wire looks okay - Sparklite indicates strong spark - Timing has not been changed; car ran fine before the miss developed - 04/30/2024: Tried a jumper across the junction box to bypass the ammeter; still no power under load; ammeter is probably okay - 05/01/2024: Reset point gap—it was too closed; improved, but still seems to miss under load - 05/02/2024: Cleaned plugs and checked gap; #4 was very sooty; improved, but still has a slight miss under load Should I be looking at something other than the plugs? Sent from my iPhone using Tapatalk |
|
05-12-2024, 08:50 PM | #6 | |
Senior Member
Join Date: Sep 2016
Location: Roanoke, VA USA
Posts: 1,955
|
Re: How many miles should spark plugs last?
Sponsored Links (Register now to hide all advertisements)
Quote:
Hmm… That sounds like spark plugs can last forever. The electrodes look fine. The gap was correct. Sent from my iPhone using Tapatalk |
|
05-12-2024, 08:51 PM | #7 |
Senior Member
Join Date: Sep 2016
Location: Roanoke, VA USA
Posts: 1,955
|
Re: How many miles should spark plugs last?
|
05-12-2024, 10:35 PM | #8 | |
Senior Member
Join Date: Jun 2014
Location: Melbourne, Australia
Posts: 7,564
|
Re: How many miles should spark plugs last?
Quote:
Seriously, the usual method of shorting out one plug at a time won't work because you are obviously driving (and under load) when it acts up. All I can suggest from here is try replacing each plug, one at a time and when the issue disappears, you found it. Do one plug at a time.
__________________
I'm part of the only ever generation with an analogue childhood and a digital adulthood. |
|
05-13-2024, 12:38 AM | #9 |
Senior Member
Join Date: May 2010
Location: Portland, Oregon
Posts: 5,925
|
Re: How many miles should spark plugs last?
I worked in a service station in high school in 1961, and one of the services we offered was cleaning plugs. We had a special machine and some kind of electrical device that told us whether the plug was good or not. I wish I had bought that machine when the station closed. I’ve never seen or heard of anything like it since.
(PS: or service vehicle was a 1930 Model A pickup.)
__________________
Ray Horton, Portland, OR As you go through life, keep your eye on the donut, not the hole. |
05-13-2024, 04:21 AM | #10 | |
Senior Member
Join Date: Sep 2016
Location: Roanoke, VA USA
Posts: 1,955
|
Re: How many miles should spark plugs last?
Quote:
Was the spark plug tester somewhat similar to this? Spark Plug Tester Dual Holes, Automotive Engine Ignition Coil Tester 0-6000rpm Working Frequency, Car Spark Tester Tool with Protective Cover for 12V Gasoline Vehicles https://a.co/d/7oXPzzE Sent from my iPhone using Tapatalk |
|
05-13-2024, 05:59 AM | #11 |
Senior Member
Join Date: Jan 2012
Location: Western North Carolina
Posts: 4,064
|
Re: How many miles should spark plugs last?
Buy a new set of plugs and install them. If you still have the miss then it was not the plugs.
__________________
A is for apple, green as the sky. Step on the gas, for tomorrow I die. Forget the brakes, they really don't work. The clutch always sticks, and starts with a jerk. My car grows red hair, and flies through the air. Driving's a blast, a blast from the past. |
05-13-2024, 07:20 AM | #12 |
Senior Member
Join Date: Mar 2017
Location: Connecticut Shoreline
Posts: 1,843
|
Re: How many miles should spark plugs last?
Model A Ford owners are known to be cheap. This is not always a compliment to the way some of our cars are being maintained.
If your to the point that never changing your spark plugs is a thing of pride? Your car most likely has other items that have deferred maintenance issues. It may still be running, but how much better would it run with a set of new plugs? Do you ever change the points or just keep filing them down? Still driving on 20 year old tires? Haven’t changed your radiator hoses ever? Still running steel original engine fan? Rebuilding worn out springs? Why replace a really old radiator, just add a little vinegar and repaint it, it only boils over when it’s hot out? Car only shimmies when I hit a bump or railroad tracks? When you go to sell your car. If it has been well maintained? You will see that return in the price you will be able to get for the car. Preventive maintenance! Even antique cars can benefit from it. |
05-13-2024, 08:16 AM | #13 | |
Senior Member
Join Date: Sep 2016
Location: Roanoke, VA USA
Posts: 1,955
|
How many miles should spark plugs last?
Quote:
Thanks for the response. However, this is not a matter of me being cheap. I already bought a set of plugs, but I haven’t had time to install them yet. (I’m thinking the new plugs will likely “fix” the miss, but I’ve been out of town and have not had a chance to work on the car for several days.) Personally, I’d like to know what the real issue with the miss is; so, in my initial post, I asked how long a set of plugs should last. I don’t think anyone has posted an answer to that yet. I don’t see any point in stretching parts beyond their expected lifespan, but tossing out something that should still have life in it is probably not a good plan either. I was just trying to get a reasonable expectation of how long (in miles, not number of years of minimal driving) for the lifespan of spark plugs. I do make every effort to keep the car well maintained, including frequent oil changes and chassis lubes. Sent from my iPhone using Tapatalk |
|
05-13-2024, 08:20 AM | #14 |
Senior Member
Join Date: Dec 2017
Location: Guthrie, OK
Posts: 1,155
|
Re: How many miles should spark plugs last?
I've been running OEM in my 2008 Ranger 4.0L for 96K miles so far. Runs so well I never have given the plugs a thought. Throw money at it. Plugs are cheap enough.
|
05-13-2024, 08:38 AM | #15 |
Senior Member
Join Date: May 2010
Location: Clinton,WA/Whidbey Island
Posts: 4,162
|
Re: How many miles should spark plugs last?
83,467 miles on a set of plugs!
__________________
www.whidbeymodelaclub.com |
05-13-2024, 10:15 AM | #16 | |
Senior Member
Join Date: Sep 2016
Location: Roanoke, VA USA
Posts: 1,955
|
Re: How many miles should spark plugs last?
Quote:
Yeah, I agree. Newer cars can run extended periods of time on plugs without maintenance. I have 108K on my 2012 Honda Odyssey plugs and 118K on my 2008 Mazda Miata plugs. I have not cleaned or gapped either set since new, and both cars run like new. My first car was a 1971 Buick, and I do recall having to clean the plugs often in the 1970s. A new set of plugs frequently “fixed” performance issues back then. I see a LOT of old spark plugs at swap meets. Does that mean that old Model A plug tend to last forever? (I’m guessing not.) I’m thinking a lot of those old swap meet plugs had issues when they were removed from the cars. Sent from my iPhone using Tapatalk |
|
05-13-2024, 10:23 AM | #17 |
Senior Member
Join Date: May 2012
Location: Chillicothe, Missouri
Posts: 1,212
|
Re: How many miles should spark plugs last?
1 of the few benefits to our modern gas that is lead free is that your spark plugs will last almost indefinitely and you have minimal carbon build up!!!
__________________
"If I asked people what they wanted they would have said faster horses." -Henry Ford "Primitive technology is not a design flaw" 1928 Ford Model A Roadster Pickup 1930 Gordon Smith Air Compressor 1941 Willy's Pickup 1960 Thunderbird-For Sale 1964 Buick Riviera 2x4 425 1965 Pontiac GTO, 455 Super Duty 2004 Dodge Ram SRT-10, V-10 Viper 1977 Charger Jet Boat,460 Ford,Jacuzzi Jet Front Engine Nostalgia Dragster,Supercharged 296 "Fullrace Flathead" Ford Engine Build up on DVD ask |
05-13-2024, 10:34 AM | #18 |
Senior Member
Join Date: Sep 2016
Location: Roanoke, VA USA
Posts: 1,955
|
Re: How many miles should spark plugs last?
|
05-13-2024, 11:22 AM | #19 |
Senior Member
Join Date: Jun 2010
Location: San Antonio, Texas
Posts: 16,511
|
Re: How many miles should spark plugs last?
How long the electrodes last depends on what they are made from. The resistors are another fail point in plugs so equipped. If you purchase iridium electrode plugs then the resistor will likely be the first weak link to go.
In aviation we had to clean the plugs on every 100-hour inspection. The Champion spark plug cleaner/tester was the best back in the day. The plug is held in a rubber bushing while abrasive blasting cleaned the electrodes at the push of a button. Compressed air was connected for testing. After cleaning, the plug is screwed into the test chamber and 120 psi of compressed air was applied to the chamber with a little thumb wheel attached to an internal pressure regulator. The tester has a vibrator coil to operate the ignition coil that is connected to the plug with a high tension lead. The push of a button activates the high tension sparking of the subject plug to be tested. The operator then watches through a view port that has a mirror to reflect the window into the test chamber so the spark can be visually verified for at least one minute. If it holds up under that pressure for one minute then it is good to go. These testers cost over $1,800 bucks at some sources now days so most folks can't justify them. A bad plug will quit sparking before it reaches 1 minute. The test has to be performed on a plug that has been cleaned and properly gapped to specs. We used iridium fine wire plugs on all the helicopter engines since they would last as long as 800 hours with careful operation and proper maintenance. Aircraft use hour meters instead of odometers so everything is in hours. On the small piston type helicopters, I always figured 60 to figure for 60 miles an hour average speed between hovering and 80 miles an hour top end so it is just an approximate of mileage and not real accurate at that but that figured 800 times 60 to equal 48,000 miles. The plugs cost around $105 each so a set of plugs was well over $800 for a set of 8 plugs for a 4-cylinder aircraft engine that has two plugs per cylinder. Some folks thought that too high so they purchase the heavy electrode plugs for around $50 each. They were worn out by 250-hours so a person was ahead of the game to purchase the iridium fine wire types even though they were more than twice the price. Automotive plugs don't take near the beating of an aircraft plug so they can last a lot longer. Platinum and iridium plugs are available for them too but they are expensive. I use the iridium ones on my wife's 4.6 L Ford V8 due to the difficulty factor in replacement. The coils last around 100,000 miles before one or two start getting weak so I replace all 8 coils every 100,000 miles along with the plugs. Here is a good tester. https://pilotjohn.com/new/champion/c...hoCMWkQAvD_BwE Last edited by rotorwrench; 05-13-2024 at 11:28 AM. |
05-13-2024, 12:18 PM | #20 |
Senior Member
Join Date: Sep 2016
Location: Roanoke, VA USA
Posts: 1,955
|
Re: How many miles should spark plugs last?
Wow. Interesting information.
I do recall spark plug cleaners from my teenage days. Even K-Mart sold some sort of cheapie, dumbed down device “for the masses.” I think it looked something like this. Sent from my iPhone using Tapatalk |
05-13-2024, 12:23 PM | #21 |
Senior Member
Join Date: Jun 2015
Location: Red Deer, Alberta
Posts: 5,085
|
Re: How many miles should spark plugs last?
Swap # 4 plug around w/another plug, drive it around for a while then check the plug that is in #4 and also the plug that was previously in #4.
__________________
If you don't hear a rumor by 10 AM, start one!. Got my education out behind the barn! |
05-13-2024, 01:14 PM | #22 |
Senior Member
Join Date: May 2016
Location: Scottsdale, Arizona
Posts: 620
|
Re: How many miles should spark plugs last?
Good Morning all...The other day I realized that my 2016 Jeep Patroit owner's manual suggests changing the plugs at 60,000 miles. I have 74,000 miles...so we changed the plugs...the difference in performance was actually surprising. SO I changed the plugs in my 1931 Model A Tudor which has had the same plugs for the 19 years that I have had the car. The same thing happened...much improved performance. I had not noticed a loss of preformance in either machine...I suggest changing the plugs...Just my personal experience...Ernie in Arizona
|
Sponsored Links (Register now to hide all advertisements) |
|
05-13-2024, 01:45 PM | #23 |
Senior Member
Join Date: Mar 2017
Location: Connecticut Shoreline
Posts: 1,843
|
Re: How many miles should spark plugs last?
Reading some of the comments posted here makes getting a Carfax report even more important.
If your driving a modern car that has not had its plugs changed in over 100,000 miles and you think it runs like new? What else have you not had serviced? What does the manufacture recommend for service? Do you care? I stand by my comment. “Model A Ford owners are known to be cheap”. Shade tree mechanics don’t always fix things correctly. Our cars were always well maintained. When it was time to sell, condition was never a question. Mechanically, they were 100%. 60 years, never broken down on the side of the road. To each his own. |
05-13-2024, 03:02 PM | #24 | |
Senior Member
Join Date: Sep 2016
Location: Roanoke, VA USA
Posts: 1,955
|
Re: How many miles should spark plugs last?
Quote:
Good idea. #4 was the culprit. Now, I’ll change the rest of them. For what it’s worth, I’m moving from Motorcraft TT10 plugs to Champion 518 (W18) plugs. The electrodes on the new plugs are much stiffer (to the point this at the plugs want to bend my gapping tool). I don’t know what other differences are likely, but it appears that I am past the miss. Sent from my iPhone using Tapatalk |
|
05-13-2024, 03:36 PM | #25 |
Senior Member
Join Date: May 2010
Location: Clinton,WA/Whidbey Island
Posts: 4,162
|
Re: How many miles should spark plugs last?
Here's a couple I have!
__________________
www.whidbeymodelaclub.com |
05-13-2024, 04:44 PM | #26 |
Senior Member
Join Date: Jan 2012
Location: Western North Carolina
Posts: 4,064
|
Re: How many miles should spark plugs last?
Sponsored Links (Register now to hide all advertisements)
RotorWrench in Post #19 said that the spark plug tester he used for airplanes put 120 psi on the plugs. Higher pressure air is more resistant to electrical current than lower pressure air. So a plug that is operating OK on top of the head may not work OK when under the pressure of compression.
__________________
A is for apple, green as the sky. Step on the gas, for tomorrow I die. Forget the brakes, they really don't work. The clutch always sticks, and starts with a jerk. My car grows red hair, and flies through the air. Driving's a blast, a blast from the past. |
05-13-2024, 06:07 PM | #27 |
Senior Member
Join Date: Sep 2022
Location: San Antonio Texas
Posts: 253
|
Re: How many miles should spark plugs last?
(Warning: tangent ahead) Gary in WA - Those little compressed air-powered abrasive spark plug cleaners brought me back to 1974. I was working as a mechanic’s helper at a Kawasaki motorcycle dealer in an era when they had a full range of bikes, both street and dirt, but only one had a four stroke engine, the rest having two strokes. These were relatively advanced in that you didn’t mix the oil into the gasoline, every model had “automatic oil injection”, a fancy term for a little plunger pump run off the crank. Motorcycle sales were booming, meaning most of the customers were buying their very first bike, and many were unfamiliar or uncomfortable with the necessary practice of keeping the revs high so the plug (or plugs) wouldn’t foul. So every Monday we got lots of customers bringing in their bikes, baffled about what happened to the pep of their brand new toy. Pull the plug(s) and they were, predictably, black with oil. A few seconds in the plug cleaner made them shiny again, blow out any remaining abrasive grit, check the gap, and they were on their way again. Perhaps the sales guy instructed them to wring it out? I don’t know. I don’t know how other shops operated, but that plug cleaner was used so often we had it mounted to the wall like the pencil sharpener was in elementary school. One pretty big guy brought in his little 125cc scrambler. The plug was fine but the fiber surfaces of the multi-plate clutch were almost completely gone. Turned out he knew all about keeping the revs up, but he was reluctant to downshift. So he just kept the throttle pinned and slipped the clutch. A lot. Fixed under warranty.
__________________
David in San Antonio 1930 ('31?) Deluxe "Wretched Roadster" Restored 1957 Alamo A’s Club Last edited by David in San Antonio; 05-13-2024 at 06:10 PM. Reason: Edited to indicate the little bike under the big guy was a single cylinder. Just one plug. |
05-13-2024, 06:21 PM | #28 |
Senior Member
Join Date: Jul 2011
Location: Redondo Beach, CA
Posts: 5,911
|
Re: How many miles should spark plugs last?
Good choice. I have been running W-18 Champions (518) for years.
Last edited by Y-Blockhead; 05-13-2024 at 08:06 PM. Reason: Misspelling |
05-13-2024, 06:33 PM | #29 |
Senior Member
Join Date: May 2010
Location: Portland, Oregon
Posts: 5,925
|
Re: How many miles should spark plugs last?
That link doesn’t show anything like a tool.
__________________
Ray Horton, Portland, OR As you go through life, keep your eye on the donut, not the hole. |
05-13-2024, 06:44 PM | #30 |
Senior Member
Join Date: Sep 2016
Location: Roanoke, VA USA
Posts: 1,955
|
Re: How many miles should spark plugs last?
|
05-13-2024, 06:46 PM | #31 | |
Senior Member
Join Date: Sep 2016
Location: Roanoke, VA USA
Posts: 1,955
|
How many miles should spark plugs last?
Quote:
The reason I was reluctant to change plugs was that I was looking for the culprit that caused the issue in the first place. I was thinking replacing the plugs could mask some other problem that I had not found yet. Sent from my iPhone using Tapatalk Last edited by shew01; 05-13-2024 at 06:57 PM. |
|
05-14-2024, 07:34 AM | #32 |
Senior Member
Join Date: Sep 2022
Location: San Antonio Texas
Posts: 253
|
Re: How many miles should spark plugs last?
Shew 01 - Yes, they are sand blasters. Maybe not sand but your choice of medium. We followed up the blasting by blowing the plug by unsnapping the airline that ran the cleaner and blew out any remaining media from the plug. Took all of 60 seconds. That will be $5.04 including tax.
__________________
David in San Antonio 1930 ('31?) Deluxe "Wretched Roadster" Restored 1957 Alamo A’s Club |
05-14-2024, 10:54 AM | #33 |
Senior Member
Join Date: May 2010
Location: Clinton,WA/Whidbey Island
Posts: 4,162
|
Re: How many miles should spark plugs last?
Yes blow out good no problem. on all my 3X plugs i take apart, and tape off porcelain etc not to glass bead certain areas of plug and use my glass bead.
__________________
www.whidbeymodelaclub.com |
05-14-2024, 11:11 AM | #34 |
Senior Member
Join Date: Apr 2021
Location: Central Illinois
Posts: 520
|
Re: How many miles should spark plugs last?
post deleted since problem found
__________________
"It ain't what you know for certain that gets ya in trouble. It's what ya know for certain that just ain't so!" Last edited by Rob Doe; 05-14-2024 at 11:37 AM. |
05-14-2024, 12:20 PM | #35 |
Senior Member
Join Date: Oct 2014
Location: Central New Jersey
Posts: 418
|
Re: How many miles should spark plugs last?
Studebaker 1961 Owner's Manual: See attached. If Studebaker said it, it's good enough for me!
|
05-14-2024, 04:19 PM | #36 | |
Senior Member
Join Date: Sep 2016
Location: Roanoke, VA USA
Posts: 1,955
|
How many miles should spark plugs last?
Quote:
Very interesting. Thanks for sharing. If I applied the 10,000 mile rule to Champion 3X plugs, that would get pricy. I think I’ll stay with the Champion 518s (W18s). Sent from my iPhone using Tapatalk |
|
05-14-2024, 04:24 PM | #37 |
Senior Member
Join Date: Jun 2014
Location: Land of Lincoln
Posts: 3,164
|
Re: How many miles should spark plugs last?
There’s other plugs less expensive and run just as good or better than the 3X’s
__________________
Don't force it with a little hammer tap, tap, tap get a bigger hammer tap done |
05-14-2024, 09:25 PM | #38 |
Junior Member
Join Date: Aug 2023
Location: North Reading Ma
Posts: 5
|
Re: How many miles should spark plugs last?
Check the distributor cam or replace with a new one also check the distributor shaft bushings for wear
|
|
|
Sponsored Links (Register now to hide all advertisements) |
|