Used Spark Plugs.-

[Sea Rider]

Usually use my OB spark plugs max100 metered work hours, at 50 hours use are removed cleaned and re gapped. The old ones are still good to go if wanting using them longer at that moment, if not are thrown inside a box. In 3 cases have used 2 pair to test OB's after general maintenance, but in all 3 cases OB did not perform top as expected.

Was wondering if using old plugs stored for years, will make OB to fail, run poor. What's your experience running old plugs stored for say 1 year ?

Happy Boating

 

[jimmbo]

There should be no reason for old plugs to cause a loss of performance if, they are cleaned properly, have the electrodes filed and gapped properly, and haven't been dropped, cracking the insulator. One other thing to keep in mind is the gasket may need replacing
My 1984 Merc 115 was still using the plugs that came from the factory when I traded it in in 1998. They were surface gaps and never failed to start the engine.

 

[robert graham]

I clean all spark plugs with my Harbor Freight Spark Plug sand blaster....keeps 'em sparking like new. Still running the original plugs in my 1999 C90 2 stroke just to see how long they last......plugs just don't wear out much. Now the plugs in my Buick at 100,000 miles were warn out....center electrode actually warn down, but not so with outboards, blowers, chain saws, weedeater, etc.

 

[racerone]

Spark plugs just provide a gap for electric charge to jump across.----No reason for them to be replaced every 100 hrs !

 

[Sea Rider]

Spark plugs just provide a gap for electric charge to jump across.----No reason for them to be replaced every 100 hrs !

For what standard spark plugs cost at $ 2.00 each, it's just a $ 4.00 investment. On 2 strokes OB's plugs usually lasts way less then on 4 strokes OB's. Asume plugs have some kind of internal along tip wear, do you remenber those Champion spark plug cleaner machines, used to have a dial in which you could check overall plug condition after sanding process. . Good/bad/throw away, don't see them anymore..

This OB has been using way wrong spark plugs for long time, probably the Ignition Coil output is low and old plugs missing. Monday should have a new spark plug set to install, will see what happens. Thanks all.

Happy Boating

 

[Chris1956]

Gee, on the salt pond, the outside of the spark plugs rust and I replace them. The working ends are usually still good.

Cheap enough to do this for conventional spark plugs, not so the iridium type.

 

[Sea Rider]

Forgot to mention that spark plug tip condition will depend entirely on the Ignition Coil output. Used to have 2 / 2 strokes Evis and those used to wear middle post right under ir, formed a u shape under, along upper electrode detereoration. So threw then away at max 100 worked hours, in comparison, Tohatsu Ignition Coils doesn't wear central electrode, stays as factory delivered.

Find when cleaning or replacing spark plugs for new that OB starts faster, has better and even aceleration, better fuel consumption compared to not cleaning or changing them at all. When Power Tuner Decarbonizer is applied after cleaning or replacing spark plugs the OB smoothness achieved throughout the whole throttle range is anazing,. Well that's me, probably a isolated case..

Happy Boating

 

[Sea Rider]

Tested both 100 worked hour spark plugs in other OB and fired right up, tomarrow will test with a new Ignition Coil which seems to be the culprit why OB misses at idle and assume throughout the whole throttle range.

Happy Boating

 

[robert graham]

Spark plugs just provide a gap for electric charge to jump across.----No reason for them to be replaced every 100 hrs !

I agree 100%.....The only plugs I ever replace are those with warn out center electrodes or cracked insulators....Like I say I'm still running the original plugs in my 1999 C90 Yamaha...they look just about like new and the motor runs great. My spark plug Sandblaster runs on 150 PSI and about 5 seconds burst and plug tips/insulators are clean and white....blow off the abrasive grit with air hose, a drop of oil on the threads and back in the motor....no problem. I've read the stories about the plug washers wearing out or something....still using same old washers, so guess those stories are mostly hogwash too!....

 

[Redbarron%%]

The spark plugs may fire and the engine run, but the increased voltage tofire from the coil migh just shorten the ,ife of the them.
The plugs spark when the voltage is high enough to jump the gap and when the spark does jump the voltage quits building up.
If the plug does not fire it goes to pen circuit voltage which is very high.
Protecting the coils from stress cracking from the high voltage is why the manufacturer suggests using a spark tester or grounding the plug wires when testing and not starting the engine.
The plugs in cars are the same.
Plugs $2.00, coils $150, easy choice.
The added stress on the coil might or might not kill the coil especially not right NOW, but later.
Of course you could get lucky as well and never have a problem at all...

 

[Sea Rider]

Is there a machine to check internal spark plug degradation if there's any ? Don't buy for plugs to last forever, plug manufacturers would have gone bankrupt long time go if that were true. On 2 strokes 2 cylinders OB's the upper plug degrades, burns more than the lower one, the look is notorious when removing them. At $ 2.20 each why not change them each 100 meterd worked hours..

Nobody has answered if those Champion Cleaning Machines with a round gauge are still being used at the service stations ? Those machines read overall plug condition.

Happy Boating

 

[racerone]

Those machines are not used anymore !----For the simple reason that labour costs today quickly add up to the cost of new parts.-----Same as brake rotors.---Same for starters / alternators.--It is cheaper / no returns / more profitable to take new parts out of a box than to repair.-----Also the public wants their car / boat repaired today and not " maybe next week "

 

[Faztbullet]

I got a old AC/Delco one that worked great in storage. You could clean and then test plug under air pressure to see if spark would blow out under compression. Also have a growler and flywheel remagnetizer in one of the barns....

 

[racerone]

I see a lot of " old time tools " in museums.----Factories with robots build stuff so cheap that repairing stuff is becoming a thing of the past.

 

[Chris1956]

Yes, but Brake Routers used to be expensive (say $120, 20 years ago). Today they are $25-$40 new, versus cutting them for $15. Of course, cutting them often fails due to thickness limits.

 

[Chris1956]

Err, make that "brake rotors"...

 

[82rude]

F250 (used) rotors make great anchors.

 

[jimmbo]

F250 (used) rotors make great anchors.

Why limit it to the Rotors? The entire truck would make an outstanding anchor

 

[82rude]

Hardy har har har.