The Stovebolt Site Forums The Shop Area Engine Shop spark plugs hotter?

Hello, Been awhile. Was doing a tuneup this week and it looks like the old plugs on my 235 are a bit sooty . r45 would a hotter plug stay cleaner ? It dosent get out on the highway alot. mostly under 40. or should i look at to rich carb? Thanks for any guidence

Use the extended tip type plugs like R45S or R44S. You probably need to look at the carb too. It probably has a Roch. model B carb which is notorious for running rich if not working right. To me its not as bad of a carb like some of the criticism it gets. There are lots of advise on how to repair it on this website.
George

For the cost of one set of spark plugs, it's possible to purchase a hand bead blaster that will let you recycle those sooty plugs many times. You can tinker with carburetor mixture to find the sweet spot between plug heat range, power valve opening point, and jet size, without spending a fortune on spark plugs. Back in my round track racing days, we ran the same three sets of plugs all season by bead blasting them once a week and swapping plugs and carburetor jets to match the track conditions every Saturday night.

https://www.harborfreight.com/1-liter-abrasive-blast-gun-92857.html

Jerry

I remember those plug cleaners. Think AC made one that ran of the shops air and had a small bag of media to clean with.

That's a real good point Jerry. Here's another model made just for spark plugs that's a little cheaper, although I've suspected you could use it to remove grease, etc from your fingertips. Why don't you try that and let us know how it works?

https://tinyurl.com/hhh8t4sa

Another plug that runs a bit hotter and works well is Champion RJ18YC6. You can find those on eBay that are New Old Stock for usually 8 for $10 to $12 (incl shipping) and the older ones were made in the USA. If you're using Tom Langdon's mini-hei distributor, this is the plug he suggests using and I've had good luck with them, too.

I used a sneaky trick to protect my fingers- - - -a small piece of aluminum plate with holes in it threaded for the plugs, held with a pair of vise grips during the cleaning operation. A quick blast of compressed air completed the cleaning procedure. We carried a few sets of plugs in the tool box that way, already gapped and ready to install. The plate also kept the bead blast media out of the threads.
Jerry

What kind of media do you use in something like that?

There are things people will tell you are ok and there are things people will say should not be used. I've heard glass bead media should be avoided because the tiny balls can work their way between the electrode and the ceramic insulator...become jammed in that space and then fall back inside the cylinder when the plug heats and that space expands, but I don't know. I've always just used the media that comes with the cleaner. It lasts a long time and the only thing you have to do is to smack them a bit against a piece of wood or such to dislodge any particles that might remain. Now having said this, a friend uses a MAPP torch torch to clean plugs. He heats them up and when they cool he wipes off the ash with a small stainless brush. Or you could duct tape them all to that part in your dishwasher that spins around and run them through a couple of cycles. Use lots of duct tape if you do this and take some digital images for us.

I used a cabinet-type bead blaster and plain old fine grit glass beads, and had no problems during several years of running the plugs in 700+ HP round track race engines that cost well over $10k each. I think a lot of those so-called problems are pipe dreams thought up by people who smoke some really high-quality wacky weed!
Jerry

I use a special spark plug cleaning sand. It is available at some part stores & tool stores.
George

If someone is concerned about glass beads causing problems, use baking soda as a blast media. It's water soluble and a quick dunk in boiling water will dissolve it completely.
Jerry

Back to my origional question. Would a hoter plug like a r46 be better to slow the fowling ? or clean these and look at the carb.

Hotter plugs will help somewhat, as long as you don't do much heavy load pulling at full throttle. If the tip of the plug gets hot enough to pre-ignite the mixture before the spark happens, it causes detonation, and possible serious piston and/or valve damage. Hotter plugs were recommended for engines that were primarily used for short trips and stop and go driving, with little or no highway mileage to burn deposits away. I'd begin with a set of new, or cleaned-up mid-range plugs and look for over-rich fuel conditions before going to a hotter plug.
Jerry

If you are using a Rochester B or BC, please look carefully at the carburetor. Hundreds of thousands of electrons have been spent discussing it and if you're running rich it is nearly a promise your power piston is stuck in the down position. And that could be for a few different reasons including the worst...your castings are warped and you're losing the vacuum you need to make the oddball Rochester power circuit work. If that is the case, a hotter plug won't help. There's no way the 235 can burn all the gas a poorly operating Rochester B will pour into it. Good luck. If you need more information about repairing the Rochester, about 3 years ago I wrote some instructions showing how you can straighten it using a simple jig made out of a flat piece of 3/8" steel, four screws/nuts and your gas grill.

Are you burning excessive amounts of oil? Ford guys used hotter plugs in a futile attempt to make their oil burners run better.

"Hire a kid to ride on the fender and dribble gasoline from a leaky cowboy boot into the intake!" That's been suggested as an alternative to running a Rochester B on several occasions!

Jerry

Except today you would need to have wi-fi so the kid could play his iPad games while riding on the fender, wouldn't you?

Where are the carburetor instructions at? Have you tried any other carburetors from a place called Daytona? I am pleased with them, it takes a little manipulating, but I have been well satisfied with the end results>

A new Daytona carb might be better than a worn out Rochester, but the "one size fits none" concept that the aftermarket stuff built by unskilled labor in some third world country suggests that it's probably starting the race half a lap behind- - - -or more! Yes, the engine will run. Is it going to be an improvement? Maybe!
Jerry

Here are the instructions I wrote on straightening the Rochester B. There is a different set just as long discussing all of the Rochester B and BC problems, but some of the links to images went away when photobucket died and I need to transfer/revive them.

https://tinyurl.com/7tm63rst