Spark plugs

[nomochevys]

I have some equipment that is going on 12 years old and I have never changed the plugs in any of them.

First is a 14 hp vanguard engine with 500 hours, and a stihl blower and shindiawa weed wacker. All are the same age and still run like new the best I can tell.

Should I change the plugs out? Gotta a briggs 3.5 push mower and god only knows that last time it had a new spark plug.

I try to keep things up as far as oil and filters go but I have really let the spark plugs go. Should I change them for new one as a precautionary measure?

 

[SuperDave456]

How much are plugs? $2.50 maybe $3.00?
That's cheaper than a quart of synthetic.

Go ahead and change them. Although you might need some penetrating oil to get them out.

My bet is that you will see an increase in power. But who knows?
Of course there is the "if it ain't broke" line of reasoning. But then again this IS BITOG, and we don't believe in not tinkering with anything.

 

[beech277]

I'd do a general inspection on the plugs. Check the gap, are the electrodes rounded, and does it still have a tan color. Also, does your equipment run to your satisfaction? If it passes those checks let it ride. But, if your still not satisfied plugs are cheap enough.

 

[tinmanSC]

ouch. getting those out might be a problem. take pics!

 

[nomochevys]

Originally Posted By: SuperDave456
How much are plugs? $2.50 maybe $3.00?
That's cheaper than a quart of synthetic.

Go ahead and change them. Although you might need some penetrating oil to get them out.

My bet is that you will see an increase in power. But who knows?
Of course there is the "if it ain't broke" line of reasoning. But then again this IS BITOG, and we don't believe in not tinkering with anything.


I have a tack on the 14 vanguard and it still turns almost to the tee the same rpm as it did new. So I doubt I would see any gain in performance. But, plugs are cheap. I think they are all champion but I could be wrong. I have never had them out to even look at them. Never had a reason to check them to be honest. Im a bit ashamed of myself to be honest and I dont even know what the manuals say about changing them.

 

[exranger06]

Originally Posted By: beech277
I'd do a general inspection on the plugs. Check the gap, are the electrodes rounded, and does it still have a tan color. Also, does your equipment run to your satisfaction? If it passes those checks let it ride. But, if your still not satisfied plugs are cheap enough.



+1. My OPE gets plug changes on an as-needed basis only.

 

[ARCOgraphite]

I replaced the plug in my b&s 3.5hp mower with the equivalent newer design B&S plug (they didnt have a non-extended reach plug!) It runs much worse and starts poorly. I might put the 17 YO plug back in.

 

[ARCOgraphite]

I wouldnt touch them if you dont see any problems. It's not like its an aircraft that would fall out of the sky if all 3 electrodes and both plugs failed. Plus 500 hours is not much for a plug. My car get >>500 hours in a year! After 49 years of working on engines - DONT MESS WITH HIGH TENSION IGNITION UNLESS YOU VERIFY YOU HAVE AN IGNITION SPECIC PROBLEM! It a miracle the spark get to the plug(s) 99% of the time with the system perfect.

 

[nomochevys]

Originally Posted By: ARCOgraphite
I wouldnt touch them if you dont see any problems. It's not like its an aircraft that would fall out of the sky if all 3 electrodes and both plugs failed. Plus 500 hours is not much for a plug. My car get >>500 hours in a year! After 49 years of working on engines - DONT MESS WITH HIGH TENSION IGNITION UNLESS YOU VERIFY YOU HAVE AN IGNITION SPECIC PROBLEM! It a miracle the spark get to the plug(s) 99% of the time with the system perfect.


LOL, Im glad its not an airplane. I think I will just run them until I have a problem. I may go ahead and buy some new plugs and store them away for a rainy day when the time comes though. My dad has a 16 hp inteck briggs and the plugs failed at about 200 hours. The engine just quit. New plugs solved the problem. I suspect the carb tuning is on the rich side in his case. The inteck does not have the best reputation anyway but his has been solid at 300 hours though it does use a bit of oil and always has since new.

 

[greenaccord02]

They probably need to be re-gapped. I'd remove, clean, inspect regap and replace them.

 

[boraticus]

Originally Posted By: greenaccord02
They probably need to be re-gapped. I'd remove, clean, inspect regap and replace them.


I agree.

If the plug is still working at all rpms, there's no need to replace it. I ran the original plug in my 1984 Jonsereds for over 25 years. It finally gave up the ghost last year so I put a new plug in. No difference in performance than with the old plug.

Keep a spare plug handy but don't change it until the old one fails.

 

[nomochevys]

Originally Posted By: boraticus
Originally Posted By: greenaccord02
They probably need to be re-gapped. I'd remove, clean, inspect regap and replace them.


I agree.

If the plug is still working at all rpms, there's no need to replace it. I ran the original plug in my 1984 Jonsereds for over 25 years. It finally gave up the ghost last year so I put a new plug in. No difference in performance than with the old plug.

Keep a spare plug handy but don't change it until the old one fails.


Probably sound advice. I am going to buy some new spark plugs and just tuck them away for a rainy day. Im am surprised the 2 cycle engines have held up as well as they have. 12 years on plugs is pretty good and I run both of them quite a bit.