85 FB

Is it me or does it seem that the rotary engine will "wear out" plugs faster than a piston engine? I checked out my cap, rotor and plugs this weekend, and noticed that the spark plugs looked ready to be replaced (the typical carbon look on their tips), and some (typical) wear on the contact points of the cap and rotor.

I checked my repair log and saw that I replaced these things 5 months/3000 miles ago. Ignition coils were replaced sometime last year. I know on a piston engine you can do this type of tune-up a lot longer than that timeframe. The Haynes manual says every 30 months or 30,000 miles. Is this usual of a rotary engine?

And, yes, my engine is running just fine. The idle is a bit low which would explain the plugs and cap/rotor.

Siraniko

iTrader: (13)

At least once a month for me. Cleaning the spark plugs and slighly sanding the cap and rotor.

Then annual basis or every new year, I replace the air in my tires as air becomes stale. (that I added for the hell of it. )

steve84GS TII

I replace my plugs about every 10K miles.
Sparkplugs in rotaries are exposed to a nearly continuous combustion cycle since the intake,compression and exhaust cycles occur in other areas of the engine.Since all the plugs ever see is combustion,they get very little chance to cool off,whereas piston engine sparkplugs get to cool down during the time between firings.

hawley2373

I would double check that you have the correct spark plug. 3000 miles to wear out a spark plug is definately premature.

mazdaverx713b

iTrader: (91)

i pesonally change my plugs every two years or 6000 miles, whichever comes first. i replace them even if they still look good. i clena the cap an rotor every year and replace every 3 years regardless of mileage. i check my wires every three years. thats just me though. i'm kinda weird about the maitenance in my cars.

85 FB

While I understand your question, I've been in the auto parts business for 3 years, I know the plugs I'm getting are the correct ones. Plus, there's only one place I go to for my parts for this car and all they deal with directly is import parts. I have the right plugs in my car.


Steve, that is the most sense I've heard yet about these cars. I never once gave that any thought. Thanks.

How often should I replace my turn signal fluid? I think I don't have enough blinks left.

85 FB

EDIT: double-post

mikewoodkozar

steve84GS TII

FWIW.....I had very poor longevity with the stock NGK plugs after running my MSD direct fire system on my old 12A's.Porcelin errosion began showing up about every oil change and a couple times there were large chunks missing altogether.Not trying to bash NGK plugs,they are the stock replacements and I do run NGK's in my TII engine with great results,although they are surface gap 2nd gen style.
I switched over to Nippon Denso plugs with the last 12A and my 13B 4-port, and all the wear problems went away.I put almost 10K miles on one set of plugs in two engines with only normal wear showing,before I went to my TII engine.The Denso plugs were a little harder to find,but cost the same as NGK's.I ended up scoring them from a Toyota dealer of all places, since none of the parts houses could find them.

85 FB

So, should I take the number on the side of my current NGK plugs and see about converting them over to Denso plug numbers and go from there?

Siraniko

iTrader: (13)

I get my spark plugs for free from FCs and FBs at the junkyard. Pocket items. I save my best plugs for track use only.

85 FB

Man, you're really itching to get to 10K posts before the end of the year, aren't you?

steve84GS TII

Wrecking yards already make a fortune off what gets sold thorugh legit means and recycling.....more power to you wacky......and Im shooting for 3000 posts!

Im also a junkyard small parts pocketer,but I usually stick to trim items and fuses/bulbs.I dont care for the baggy pant fashion,but I sure as hell sport them when I hit the yards!

The ND plug numbers for a 1st gen are......

ND......W22EDR14.........equals........NGK......BR 7EQ14
ND......W25EDR14.........equals........NGK......BR 8EQ14
ND......W27EDR14.........equals........NGK......BR 9EQ14

http://www.postdiluvian.org/~mason/m.../ngk_to_nd.txt

85 FB

Cool, thanks, Steve. All I need to do right now is find someone who sells Nippendenso plugs. The import parts place I go to might carry them.

Siraniko

iTrader: (13)

Heres my input on spark plugs. Its true that ND's are good but NGK will do fine. Besides, 85 FB owns a stocker so whats the point?

85 FB

I just want my engine running healthy and strong. And, to not replace spark plugs everytime I change my oil.

trochoid

iTrader: (6)

ND's were the OEM plug from the factory. NGKs are an optional replacement. Both are good plugs. The FSM and Owner's Manual both list the plug numbers. If your plugs keep carboning up, you're running rich. Lean it out at idle, use the choke less and clean them more often.

Steve, interesting point on plug wear. Never looked at it that way.

85 FB

Trochoid, I don't have a choke. All EGI. And, what would I use to clean spark plugs?

mazdaverx713b

iTrader: (91)

scott, you make an interesting point. i did not know that ND were the oem plugs. fwiw, i thought that NGK plugs were installed initaially at the factory.

hawley2373

You could use a wire wheel to clean your plugs. It shines them right up. They do make a little sandblaster spark plug cleaners but I have no experience with them.

85 FB

Well, I do have a drill with a medium wire wheel brush. But, that's not going to damage the spark plug tip will it?

steve84GS TII

Wire wheels tend to burnish things up if you push too hard,although they can get some of the crud off.You have to be careful not to round off the edges of the electrodes with a rotary wire wheel.Its easy to push too hard and then all the sharp edges on the plug are gone,and sparks like to jump off the sharp edges.
The sandblaster type cleaners do a good job but its nearly impossible to get all the little beads of sand out of the little crevices down in the plug......not a good thing considering the design of the rotary engine in regards to injesting foreign matter.
I tend to not worry about cleaning plugs,unless they are really gunked up and relatively new/sharp edged.In which case,I would just use a small metal nail file to scrape and clean the working parts of the plugs only.The rest of the crud has little to no effect on the plugs ability to work,its mainly the electrodes you need to worry about.