Using A Not-Correct Sparkplug in Snowblower ?

Been a LOT of years, but IIRC it's the length of the ceramic insulator in the center. Of course, tomorrow I'll try and remember to web search the question.

Longer insulator is hotter plug.

- . Christopher A. Young learn more about Jesus .

Wrong - sorry Ralph. The heat range is determined by the length of the heat path from the center electrode in the cyl to the plug shell - so the length of the insulator INSIDE the cyl.

The operating temperature of the electrode is determined by the length of the heat transfer path from the tip to the shell. That is the CENTER tip. The ground terminal is "cold" as it is virtually connected to the head.

Nope You almost got it right. See my other posts.\\

Not quite. A ptojected nose plug sticks the tip of the electrode out into the cyl where the air/fuel charge helps cool it, giving a wider heat range. The thermal path between the tip and the shell still determines the heat range. - but Ralpf has his plug science Bass Ackwards.

A very clear, well-illustrated page. I knew most of this stuff, but it helps to see it written so clearly.

This is what it says if you use a plug that's too hot: "When the center electrode reaches 950°C or higher, pre-ignition (early ignition) occurs, meaning that the electrode serves as a heat source and ignition occurs without a spark. Therefore, output falls and this can reach the level of electrode wear and insulator damage."

Only mentions damage to the sparkplug, not the engine. The page is from a spark plug company and they should know. I've never heard of Denso Spark Plugs, so does that mean it's a faux page meant to trick us into damaging our enignes?

I've been trying to get a radio for my snow blower, but I can't find one with Sirius also.

A friend who lives in NYC was forced to sell his Cadillac, for lack of a place to park I think, and he gave me a spark plug cleaner.

You may have seen an add for these.

AC-powered, and filled with little glass pellets, it blows the glass against the end of the plug and cleans them up nicely. Takes a minute or two per plug. Some of the glass bits tend to stay between the insulator and the shell but come out when tapped.

But with the hot sparks on cars these day, I never clean my plugs and even if I had a gas garden tools, I'd need a bigger shop to keep this thing availalbe. So I've only used it twice. (He included extra pellets but haven't used them yet.)

Denso is a major Japanese parts supplier, both to OEMS and aftermarket.

While they don't talk about engine damage, pre-ignition could damage an engine itself, eg the pistons. There is also the issue of the operating environment, ie is this a high performance, high compression auto engine accelerating in a 110F desert or a lower compression snowblower engine running at constant RPM when it's 20F ambient? IMO, the risk of using a similar looking sparkplug that fits, for an hour to clear snow is minimal. To further reduce any risk, the OP could use the substitute plug to see if he can get it running. Once running, put the original back in and see if it too works. Probably not the plug anyway.

I remember them. Long ago in another life, I used to take the plugs out at 5000 miles, clean them and replace them at 10,000. Now they easily last 100k. Heck, the last 5 cars I traded with original plugs, battery, exhaust system.

I used to clean a lot of plugs with the Champion plug cleaner decades ago - back when all engines were made of Cast Iron - and so were Chevy pistons. The engines back then could survive the odd grain of sand or glass bead going through - and seldom made 100,000 miles regardless. Todays aluminum engines? I wouldn't THINK of using a sandblasted plug. Particularly on today's plugs. Too much chance of stray beads staying in the plug, coming out in the engine, and doing damage.

Wax the plug cleaner up and set it beside your restored tire inflator in your "Man Cave" as a conversation piece.

My 19 year old p[ickup with almost 3330,000km on it has had the plugs changed - not sure about the battery - it's still an OEM battery but may have been replaced before I got it. Valve covers have never been off, original exhaust and rear brakes even.

When I started in the trade brakes seldom lasted more than 3 years of easy driving, exhausts lasted a year or two at best and plugs were an annual tune up item at best. If you made 100,000 miles without at least one major overhaul you were doing VERY well.

The big problem is pre-ignition can easily progress to detonation and burn a piston. Not as likely on a snowblower in the winter as on a dust-stuffed lawn mower in the summer - but not impossible,

Denso - that's short for NipponDenso - which is a very large Japanese auto-electric company and one of 2 OEM manufacturers for Toyota spark plugs. Not sure about present, but at least at one time in the past NipponDenso was majority owned by Toyota. Toyota's second source for plugs was NGK. I do tend to see more NGK than NipponDenso in the North American built Toyotas.

You can say it until you're blue , some just can't grasp the concept of heat transfer path . Shorter path equals colder plug , longer is hotter . Ever seen the top of a piston subjected to extreme pre-ignition ? I've seen holes ...

I have too, What you are possibly not catching is HE is saying it is the length of the insulator OUTSIDE the engine - from the shell to the terminal. He is WRONG - I'm sure you will also agree. It is the insulator INSIDE the cyl.

Remember - I've been a mechanic for decades and taught motor vehicle technology at the post secondary and secondary level.

I admitt I was wrong in my statement about the outside of the plug. The outside of the cylinder part of the plug does get rid of some of the heat,but it is mainly the part that is inside the cylinder of the plug that determins the heat range.

I mainly had it backwards to start with.

snipped-for-privacy@snyder.on.ca wrote: the last 5 cars I traded with original plugs, battery,

I am still driving my 1968 Chevy K10 suburban 4WD, no power brakes or steering, manual 4 speed. Runs good, had a 307 I believe but I had a 350 put in about 20 years ago--I have about 150,000 miles on it but may have to retire it as I need a steering gear for it and they are hard to find. I use it in the winter or as my fishing transportation in the summer.

JAS

...and this has something to do with spark plugs or the heat-range there of?

Sorry