Platinum or Iridium Plugs for OPE?

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Somewhere within the next 4-5 weeks all of the lawn toys are going to come out of hibernation. Four machines haven't seen a new spark plug in three or more years, including two Honda GCV-160, one Chonda in the generator, and a 22 HP Briggs V-Twin in the lawn tractor. Given that the difference in spark plug prices is not that much and the time to replace them is the same, are there any strong reasons for or against upgrading the plugs? Is there any reason not to throw a couple of extra bucks at these plugs?
 
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My zero turn kawasaki engine hit 100 hours, so i bought replacement spark plugs. When i took the old ones out , the looked unworn. I put them back in. I'm not sure about 2 cycle, but i'm not sure you need anything more than standard non platinum plugs.
 
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Originally Posted By: spasm3
My zero turn kawasaki engine hit 100 hours, so i bought replacement spark plugs. When i took the old ones out , the looked unworn. I put them back in. I'm not sure about 2 cycle, but i'm not sure you need anything more than standard non platinum plugs.
Thanks spasm3! That was my suspicion as well, but I am tempted to try this in at least one machine, possibly the one with the V-Twin. OTOH, the generator with the Chonda motor is the one that I really care about starting when needed.
 
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I switched everything to iridium except the lawnmower and that small plug is a B&S platinum. I have some observations that may help you decide, nothing scientific. My wife could not start the lawnmower ever, I had to start it. With the platinum plug she can start it first pull, same mower, same oil only the plug being different. The precious metal plugs require much lower voltage to fire, that the explanation. The snowblower does exactly the same route every storm, again same oil (changed yearly) nothing else different. For the first 8 yrs in a storm 4 inches or more I had to refill the tank about 3/4 through, it could never finish the job without. With the iridium it completes the job easily even in a 20+ inch storm and is still not empty. If I had to guess its doing at least 30% better on fuel (I am not saying the results in a car engine will be the same). This thing with its algore carb runs pig rich, if you idle it for a minute and throttle back up it blew lack smoke out, now it doesn't, it idles fine. I can only attribute this again to the lower firing voltage requirement of the plug with a magneto ignition. It always started first pull and never needed the 12V electric starter. Before I got a gas fueled generator I noticed significant improvements in fuel economy with the gasoline powered one.
 
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I wonder how/where do you find (proper) Iridium sparkplugs for OPE? You can match/crossreference them from automotive use.....but then heat range is not right... champion RJ19LM....no way that you get that as iridium smile
 
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The only reason platinum and iridium spark plugs are made is for vehicle engines that run hotter, leaner fuel mixtures to meet emissions control requirements AND have a long service life while doing it! Garden equipment applications simply can't push conventional plugs hard enough to make a difference!
 
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Waco, TX
Originally Posted By: spasm3
......... I bought replacement spark plugs. When I took the old ones out, they looked unworn. I put them back in.
I never seem to wear out spark plugs in any OPE, either. I have fouled a few in chainsaws over many years (27?) but never worn one out.
 
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4,215
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Central Wisconsin
Quote:
"I wonder how/where do you find (proper) Iridium sparkplugs for OPE?"
I tried to find a Iridium plug a couple of years ago and couldn't. Found a similar number for an auto but the standard gap was .060 or some such. I ended up adjusting it down to what Briggs called for and it worked and continues to work fine for several years now. Starts good runs good. My 2¢
 
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Sweden
I have not tried iridium plugs on ope but you are stating that the plug change somehow improves fuel consumption in a snow blower. Since you are running it att full throttle and there is no feedback or connection between the ignition and carb that is simply impossible unless the plugs allows you to run it at lower RPM (which I doubt, did you reduce throttle?) The carb will feed exactly the same amount of fuel to the engine at a certain rpm regardless of plug. Unless you snowblower is equipped with a full ECM this is unreasonable and more likely a seat of the pants situation. Sorry, but that is likely it. About the tarting though, that's interesting! MAybe I will try those plugs to ease starting!
Originally Posted By: Trav
I switched everything to iridium except the lawnmower and that small plug is a B&S platinum. I have some observations that may help you decide, nothing scientific. My wife could not start the lawnmower ever, I had to start it. With the platinum plug she can start it first pull, same mower, same oil only the plug being different. The precious metal plugs require much lower voltage to fire, that the explanation. The snowblower does exactly the same route every storm, again same oil (changed yearly) nothing else different. For the first 8 yrs in a storm 4 inches or more I had to refill the tank about 3/4 through, it could never finish the job without. With the iridium it completes the job easily even in a 20+ inch storm and is still not empty. If I had to guess its doing at least 30% better on fuel (I am not saying the results in a car engine will be the same). This thing with its algore carb runs pig rich, if you idle it for a minute and throttle back up it blew lack smoke out, now it doesn't, it idles fine. I can only attribute this again to the lower firing voltage requirement of the plug with a magneto ignition. It always started first pull and never needed the 12V electric starter. Before I got a gas fueled generator I noticed significant improvements in fuel economy with the gasoline powered one.
 
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USA
Originally Posted By: Kamele0N
I wonder how/where do you find (proper) Iridium sparkplugs for OPE? You can match/crossreference them from automotive use.....but then heat range is not right... champion RJ19LM....no way that you get that as iridium smile
Actually the Autolite XST458DP Xtreme Start Iridium Spark Plug is a cross to the champion RJ19LM
 
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MIchigan
Originally Posted By: Trav
My wife could not start the lawnmower ever, I had to start it. With the platinum plug she can start it first pull, same mower, same oil only the plug being different.
Thank you for that bit of info...now I'm thinking about getting one for my hard to start lawnmower that has no choke and seems to burn alot of gas. What brand of plug is it?
 
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Slovenia EU
Originally Posted By: smithph
Actually the Autolite XST458DP Xtreme Start Iridium Spark Plug is a cross to the champion RJ19LM
No way that I can buy that in any OPE shop/service smile But tnx anyway...will look at ebay...internet etc...
 
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1,896
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missouri
I ran an 8 HP briggs aluminum bore on 3 acres for close to 25 years and never changed the plug. The blade deck was rotted, and tyranny failing, engine needing about 6 OZ oil every hour when I scrapped the mower. Don't get carried away.
 
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Canada
"Don't get carried away." Lots of that goes on around here it seems. I've got decades of use with dozens of engines. Most have NGK, ND or Champion spark plugs. In 50 years of small engine experience, I've had maybe four spark plugs fail. There is absolutely no necessity for iridium plugs other than to placate some OCD issues.
 
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Midwest
Originally Posted By: boraticus
"Don't get carried away." Lots of that goes on around here it seems. I've got decades of use with dozens of engines. Most have NGK, ND or Champion spark plugs. In 50 years of small engine experience, I've had maybe four spark plugs fail. There is absolutely no necessity for iridium plugs other than to placate some OCD issues.
I agree with the Canadian. I just use OE plugs, which typically they recommend NGK. I've used Champion as well, never a problem with either basic plug and agree that plug failure is rare. If compression is within spec and your carb is properly spec'ed, your plug will last a long time. I do change the 2 smokes more often, but even those look pretty good after running 50:1 synthetic 2 cycle.
 
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Originally Posted By: Snagglefoot
How old are you? If you put in platinums that might be the last change you ever have to do. Iridium would be way over the top. Hey, but we’re all OCD on this forum.
Originally Posted By: Pajero
Iridium and forget about it!
I think that both of you understand my modus operendi.
Originally Posted By: Trav
My wife could not start the lawnmower ever, I had to start it. With the platinum plug she can start it first pull, same mower, same oil only the plug being different. The precious metal plugs require much lower voltage to fire, that the explanation.
Good to know. Not that my wife would ever start one of these machines, but easier starting is a definite plus. The "always starts on first pull" reports often seen here on BITOG don't match up well with my experience.
Originally Posted By: smithph
Actually the Autolite XST458DP Xtreme Start Iridium Spark Plug is a cross to the champion RJ19LM
Good to know - I have a few applications for that plug.
Originally Posted By: ragtoplvr
I ran an 8 HP briggs aluminum bore on 3 acres for close to 25 years and never changed the plug. The blade deck was rotted, and tyranny failing, engine needing about 6 OZ oil every hour when I scrapped the mower. Don't get carried away.
This is BITOG, where we live to get carried away with these things. As a matter of fact, I am absolutely convinced that my push mower that gets Mobil 1 synthetic every 30 hours will outlast the one from the guy who never changes or checks the oil or spark plug. Having said that, my oldest piece of OPE, a 33 year old Troy-Bilt tiller, is the only one that does consistently start on the first pull. I think it ran 30 years on simple Quaker State SAE 30 and Champin RJ19LM plugs changed every couple of years at best. Go figure.
 
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