dosent like champions?

[6228SH]

I have a reoccuring problem of my 62 28 johnson not firing on relativly new plugs.pulled a wire at a time and found it only running on top cyl-switched plugs and only running on lower cyl.put in old autolites it had when I bought it and it runs good.this time I am blaming it on the de carb I just did,although I heated the plugs to clean down in them beyond reach; but this has happened several times now.stops firing ,although plugs look good,havent been dropped,etc. -since I got this motor this spring,I put in a set of J4Cs and two sets ofJ6Cs. what am I missing here?

 

[F_R]

Re: dosent like champions?

There are people that will swear and be hornswoggled that Champions are no good. But the same thing goes for all the other brands too. I say it is the motor. Something about it is causing the plugs to short out.

 

[JB]

Re: dosent like champions?

Check out your magnetos, SH. That engine should run fine on clean Champion J4Cs gapped at .030". If it doesn't it is not the fault of the plugs.

Points should be clean and gapped at .020", condensors good, coils not cracked, coil core to flywheel clearance about .010".

 

[6228SH]

Re: dosent like champions?

I didnt mean to imply champs were no good-I did recently put on new coils,condensors, and points-I'll pull the flywheel tommorow and check things out.I didnt use a feeler guage to set the coils' clearance but set them flush with the mounting pegs(for lack of proper term)- I have wondered if the point gaps are wrong as I did not know to use the flywheel key to line them up with but rather tried to see the furthest open point by eyesight and match that point on the other set-

 

[OptsyEagle]

Re: dosent like champions?

I use J6Cs in my 1961 5.5Hp Johnson and have not had any problem.

I de-carbed it last week and when I looked at the plugs, they looked fine to me, so I didn't bother changing them. It purred like a kitten all last week with no problems at all on those Champions.

 

[6228SH]

Re: dosent like champions?

my plugs had little tiny spheres of carbon stuck on the electrodes,but I dont blame that for the lack of spark on the one plug-if nothing else,the de carb showed me that I had a cylinder only firing every once in awhile as I could see the smoke puff out when it lit up-I look forward to finding whats happening under the flywheel.I have to wait till tommorow to borrow a socket from work though.

 

[JB]

Re: dosent like champions?

J6Cs are a bit hot for general use in CD-18s, Eagle, particularly for extended high rpm running. They are okay for extended trolling if you gap them at .040" instead of .030".

The manufacturer recommends J4Cs gapped at .030" for general use.

 

[fast_eddie]

Re: dosent like champions?

As far as I know owning a 1964 28hp johnson. I don't think thier is a way to check coil to flywheel clearance. You just make sure that the coils laminated steel is lined up with the standoffs that the coil mounts on top of. front of coil laminate is not supposed to be overhanging on the standoffs as the flywheel can hit the coil and destroy it.

Also I am not having much luck with champions in mine either. Missing on a cylinder under load. This is after replacing coils, points (gapped to .020), condensors, plugs (j4c gapped to .030) and plug wires. I am going to try a different brand. Maybe denso or autolite.

 

[6228SH]

Re: dosent like champions?

I pulled the flywheel and found on one coil evidence that it had been rubbing the flywheel. no major grinding but a shiney area. I ensured it was flush with the standoff before putting it back together. would this cause my problem?

 

[walleyehed]

Re: dosent like champions?

It may....but I have a few additions to make about the plugs...
First, I have a few of the same type of customers that say the same about champ plugs....with these customers, I ask them to allow me to install these champions and if they won't work as good or better than there "other" choice, I'll give their money back.....so far, I haven't had to cough up a dime.
Champion plugs must be torqued to right about 20ft-lbs because of the crush-ring...most folks never get even to 15ft-lbs. If the crush-ring isn't seated to these specs, the plug cannot dissapate heat and it builds resistance with-in the plug and ruins it......heating the plug with a torch to clean it can do the same.
Also, just because a plug "looks" good, doesn't mean it hasn't built that resistance that will not allow it to fire properly.

 

[6228SH]

Re: dosent like champions?

thats very interesting! my torque wrench is 1/2 "drive-my plug sockets are 3/8"-an adapter will render the torque values inaccurate wont it?

 

[JB]

Re: dosent like champions?

No. The adapter dosn't alter the torque.

 

[fast_eddie]

Re: dosent like champions?

I went to this site to cross plugs and found this out about are motors. What am I to think. It recommends Champion Q Series Copper or Platinum J8C, but not only just J8C it recommends using 876/QL16V for commercial service.
http://www.sparkplugs.com/results_appOther.asp?otherMotiveID=12503&mfid=2

champion QL16V is a surface gap racing plug. Not sure I would want to run this plug though as it is 1/2" depth plug. seems as though it would hit the piston threading in that far. J4C and J8C are only 3/8" depth. I suppose the QL16V would work though if clearance is enough due to lack of protruding electrode like on the J4C/J8C. I would have to verify clearance before trying this plug.
http://www.sparkplugs.com/more_info.asp?AAIA=&pid=8688

This is per OMC according to the site. It states use of other plugs may cause misfire.

 

[fast_eddie]

Re: dosent like champions?

Any thoughts on running j8c plugs. If this is what I am supposed to be running, wouldn't that explain why I and 6228SH are both fouling j4c plugs as they don't generate as hot a spark causing misfires and wet/carbon fouling.

 

[fast_eddie]

Re: dosent like champions?

Just put J8C plugs in my 1964 28hp RX-12. Drove around the lake once and checked them. They were tan which is good and means no fouling. When I did this with J4C plugs they came out wet and somewhat black.

 

[6228SH]

Re: dosent like champions?

That link was the first place I've seen recommending using the J8s-it sounds like you've had good results fast_eddie-

 

[mikec04]

Re: dosent like champions?

Fasteddie, the heat range of a spark plug has nothing to do with how hot the spark is. It is the rate at which the plug dissapates the heat generated by the spark jumping the gap between the positive (center) and neg (ground) electrodes. The heat of the spark has everything to do with the condition of the coils and condensors and breaker points. In the case of Champions, the higher the number (j4c, j6c, j8c), the faster it dissapates the heat, thus, a J8c is a "hotter" plug than a j4c.
I'm sure thjat if I have it backwards, someone will correct me.