Spark plug reccomendation - NGK vs Champion for '64 40HP

[AlexeiVT]

Hello,<br />I'm trying to determine what sort of spark plug to use, for best overall performance, on my '64 40HP Big Twin.<br /><br />And more specifically...why, choose one manufacturer over another? (I've searched through the archives for similar comparisons, and it seems like more people lean toward Champion for whatever reason).<br /><br />As a background...when I revived my motor, it did have Champions in it (not even sure if they were the correct spec at the time, and don't recall the #'s).<br /><br />So, when I went looking for suitable new plugs, the store I went to only had NGK's to choose from (and "B6S" was what cross referenced as being applicable).<br /><br />Well, having since installed those plugs, I've also gone through the muriad of cleaning and tweaking, carburators and decarbing...in any case, it runs well and to my satisfaction now...so the question would be, is there any reason (or at least an opinion based on experience) to try out the correct Champion plug instead?<br /><br />The NGK's probably have less than 15 hours total on them, since I only got the boat running and on the water a half dozen times last year since new...so they're definately not in "need" of replacing, just wondering if there is anything to gain w/ Champion...(I generally remove and inspect the plugs after a bit of use, and give them a quick sandblasting shot to clean up the electrodes, so everything's clean and happy to spark).<br /><br />Any suggestions, or perhaps something new to try out (I remember paying a "small ransome" for some fancy G3 or E3 next generation split tip spark plugs for my lawnmower, and it seemed to make a bit of a difference...not sure if there is an option for something newfangled that'd help out...but I can probably afford two to try, per a reccomendation). Thanks

 

[DJ]

Re: Spark plug reccomendation - NGK vs Champion for '64 40HP

ONLY put Champions in that engine.<br /><br />I'm no Champion fan, but I will NEVER put any other in an OMC (John/Rude) product.<br /><br />Been there, tried it, wasn't happy.

 

[AlexeiVT]

Re: Spark plug reccomendation - NGK vs Champion for '64 40HP

J4C is what I got from the Evinrude dealer...so I'm guessing these are correct (counter personnel didn't quite exactly seem to have the confidence I was looking for).<br /><br />I'm assuming the standard gap check, would be for .03?<br /><br />I was also trying to acquire some oil that might lead to a bit less smoking (but for all I know, that just may be the state my motor is in these days)...I've been decarboning it, and when I do it seems to still smoke a bit more even after running a while...but, it moves me along nevertheless.<br /><br />I was looking for Ficht Ram oil, but was told it was no longer available and that the Evinrude 100 or something was the replacement (but only available in quantities costing $50+, wanted to try a smaller sample of anything first, just to see if it made a difference). For now, it seems a trial w/ Pennzoil, rather than super-tech, to see if there is any initial difference.

 

[AlexeiVT]

Re: Spark plug reccomendation - NGK vs Champion for '64 40HP

Still a bit confused...<br /><br />OK, aside from whatever the previous naming convention was, and from the schematics, it shows the J4J as what's supposed to be in the motor.<br /><br />Head to the shop, and get the modern "copper" equivalent J4C.<br /><br />What confuses me, is that what was in there, were the properly (at the time, by yet another shop) cross-referenced NGK plugs that were B6S.<br /><br />However, when further looking at the chart now, the NGK B6S cross-references to match a Champion J6C.<br /><br />So my real question, since everywhere I go, I end up w/ something slightly different...is what is "right".<br /><br />What's the difference between a Champion J4C and a J6C...any reason I would want one over the other? Thanks again.

 

[steelespike]

Re: Spark plug reccomendation - NGK vs Champion for '64 40HP

It's my feeling any common brand of correct design and heat range will work properly.Though if I was getting plugs today I would do Champion<br />only because I have used them in everything I own.I've heard that artifical 2 stroke oil burns cleaner with less smoke and deposits. It is also supposed to be biodegradeable.<br /> While I seldom do it plugs should torqued to specs to work properly.Definately not tightened<br />with mighty force as if your life depended on it.

 

[wilde1j]

Re: Spark plug reccomendation - NGK vs Champion for '64 40HP

Heat range is the difference. You want whatever Champion plug the engine mfgr recomends. Forget NGK.

 

[Paul Moir]

Re: Spark plug reccomendation - NGK vs Champion for '64 40HP

The difference between the J4C and the obsolete J4J is that the ground electrode on the J4J only half-covered the centre electrode. That is to say you can file the ground electrode back a bit on the J4C and turn it into a J4J. The exposed spark helps a bit with fouling, but not enough to really matter much. <br />J6C is a little hotter and is an optional plug on your engine. If you troll most the time, it might be worth trying. The J4C provides a safety margin in the case of overheating, etc. Too cold a plug and it'll occasionally foul. Too hot and it'll burn a hole in your piston.<br />Any TC-W3 oil is infinitely better than what that engine was run with in the past. Use whatever makes you happiest. I find some of the premium type oils either smell better or smoke less, so I use them.<br />I've tried the B6S as a replacement and found it was a little too cool (if I remember right). There was something I didn't like about it but I don't remember what exactly. I'm like DJ: if I weren't talking J/E engines I wouldn't be talking Champion. Don't bother with any high tech plug because if they do anything at all, it's normally improved for 4-strokes not 2. And most the tip improvements (iridium, etc) increase life which is a moot point on an outboard where they normally die of carbon fouling rather than electrode wear.

 

[CATransplant]

Re: Spark plug reccomendation - NGK vs Champion for '64 40HP

Paul's right. Paul's almost always right. I'd add just one thing to what he said. Always carry a brand new set of properly gapped plugs of the type you use in your engine, along with a spark plug wrench, in your in-boat toolbox. <br /><br />If you foul a spark plug while on the water, it is a matter of just a few minutes to swap in a new one or a new pair, then be back on your way. Failing to have a set of plugs in the boat is a good way to get towed back to the dock.<br /><br />Your 40 isn't really bad about fouling the correct plug, but it does happen.

 

[JB]

Re: Spark plug reccomendation - NGK vs Champion for '64 40HP

The 1964 RD-26, RDS-26 and RK-26 and their 'Rude sisters all call for the Champion J4C (replacing the J4J) gapped at .030" for mainly high rpm use.<br /><br />If the engine will be operated ONLY at low rpm the J6C can be used but a better all-round plug for a mainly trolling engine is the J4C gapped at .040". That will still work for long runs at higher rpm but will improve the low speed/idle and reduce fouling.<br /><br />In summary, pretty much what Paul said.

 

[AlexeiVT]

Re: Spark plug reccomendation - NGK vs Champion for '64 40HP

Thanks again...Once this motor basically fires, it's shifted into forward, and then run near or at WOT, so the plugs usually self-clean and haven't fouled.<br /><br />Having learned the hard way on an early outing, I've been carrying spare spark plugs and a wrench since the get go.<br /><br />I'm pleased w/ the compression and power I get from this motor NOW...but in the beginning, it turns out one of the spark plug holes had been rethreaded w/ an insert. That insert eventually turned a bit, and voila!...I was then running on one cylinder since the gap went to zero, and there was nothing to spark (it did run on 1, but headed to shore).<br /><br />Then, it was funny, finally convincing everyone that this was "reliable"...loaded them up, and as soon as I got out of the cover, hit the throttle, and then...nothing. I knew I had my plug and wrench, but to my dismay, when I pulled the cover, all I saw was the other plug being held in suspension by virtue of the plug wire boot...it was pretty obvious that that day of boating ended w/ a swim/tow to shore, since the threads had been blown out of the head.<br /><br />I've heard varying opinions on how successful the rethreads would be (and went the best route I could find w/ the ones that are not only glued, but smacked into place to bite and set)...so far, so good...I gingerly removed them this year, hoping not to pull the inserts, but figuring it would...but it didn't...and through the decarb process and squirting into the cyclinders, everything is still where it's supposed to be.<br /><br />Before, as a preventative measure, I squeezed on 1 addional washer, for the plug on the cylinder that was getting squashed (as at the time, I didn't realize it had been rethreaded)...now, having since rethreaded them BOTH, I can run a plug the way it's supposed to be, w/out it getting squashed, quite a relief.<br /><br />I'm happy to have been supplied the correct plug, and verified by you folks (hey, I guess the manual is right!)...just that a while back, had a dealer that seemed to have every part I needed in stock, and it didn't seem to phase them when the motor was 40 years old, that gave me the J6's.<br /><br />But, letting the motor soak, then it's in w/ the J4's and happy boating. Thanks again.

 

[Paul Moir]

Re: Spark plug reccomendation - NGK vs Champion for '64 40HP

I think there's a good reason every modern outboard uses plugs with about 1/2" of thread rather than the 3/8" on the JxC plugs. I really do think an older Johnny/Rude with a helicoiled head is actually better than the original.<br />But whenever I'm dealing with the old aluminium threads, I use a torque wrench to install the plugs!<br /><br />(The high temperature loctite red has worked on a couple non-locking inserts for me for a few years. I don't even think about them now.)

 

[renelson177]

Re: Spark plug reccomendation - NGK vs Champion for '64 40HP

This is a good thread, sure glad I found it. The new, but uninstalled NGK B6S's are going back to the store.<br /><br />My 1972 25hp Evinrude 25253 was rebuilt just before I purchased it back in 1978. The first time I changed plugs I went by the book and bought Champ C4J's, putting the old, but still good, plugs in the toolbox. <br /><br />The next time out I couldn't even get the boat to plane, it just sorta plowed through the water, no power at all. Troubleshooting experience tells me if something is different go back to look at the last thing that was changed. I reinstalled the old C6J's and she ran like she was supposed to.<br /><br />If this motor was designed to use the C4's can someone with a lot more experience than I tell me ... or at least make an educated guess ... as to why it has to have the C6's to run properly? I have been told a couple times that I run the risk of damaging a piston with the hotter plug but so far no problem.<br /><br />The old girl has just been revived from many years of storage and this question has always bugged me.