Spark plugs

[whelanIII]

I have A 1996 90hp v4 johnson my Johnson Manual says to use QL82YC I Just was looking at the BBC plug chart and they say to use QL78YC I am a little confused as to which plugs to buy any comments as to what is the better plug I fish a lot and at times troll with it but have about a 10 mile run out and back at about 3500-4000 rpms thank you for any come backs

[SEAHORSE]

Back then Champion and OMC came up with new plug recommendations but found out that out of tune and overpropped 225hp motors using old or poor quality fuel had combustion problems. They decided that the QL78YC plugs were better for those particular model. In the interest of keeping things simple (?), they recommended that from then on all looper motors above 40hp would take the QL78YC plugs.

[whelanIII]

so would I be better to run the QL78yc in my 90hp?? are these a colder plug than the QL82yc

[Dhadley]

We assume you have the 60* looper V4, not a crossflow, right?

[Dae]

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by whelanIII &raquo;</TD></TR><TR><TD CLASS="quote">so would I be better to run the QL78yc in my 90hp?? are these a colder plug than the QL82yc</TD></TR></TABLE>

I like the original 82's better because it's a hotter plug. Like Seahorse said, the reason for the change wasn't because of the v4 loopers, but the 225 v6.


- Dae

[whelanIII]

I believe it is the 60 degree I guess i will try the colder plug and see how it runs I have one cyl. on the lower left bank that looks like it is running to hot, tip burning on plug at high rpm