plugs:surface vs standard

[david_r]

:redface:sorry JB, bream master, and everyone i didnt mean to try to hijack the thread.

i have a '79 115tl79r johnson the charts list (surface) QL16V champions or QL77JC4 champions (standard)

ive read the pages about how the engineers tested for different shapes and lengths of porcelian and found a happy medium between the fouling prob at idle and the preignition at wot.

what i was curious about is has anybody here ran both types?

if so are there any difference at wot or idle?

can anyone tell me if the surface gap plugs really last longer than a standard plug?

sorry again guys.

thanks for any help. this is a great site!

 

[JB]

Re: plugs:surface vs standard

I had a '79 Johnny 70 that used surface gap plugs and a couple of 80s 70s that used "regular" plugs. I noticed no difference in operation of these loop scavenged engines. I don't know if that experience transfers to the cross scavenged V4s, though.

 

[nguoi_viet41]

Re: plugs:surface vs standard

I had a '79 Johnny 150hp that used surface gap plugs and in the regular plugs. I see no difference too

 

[david_r]

Re: plugs:surface vs standard

thanks for the info guys. i was just wondering if i wasted $16 on standard or if i should have waited and ordered the surface. i already now have 2 sets of ngk that i bought before i decided to listen to reason and go with the oem specs., it seems like it warms a little faster, it could just be coicidence but it seems to idle better.

i read the surface gaps lasted a LOT longer is this a myth?

thanks for the help and info guys.

 

[jimmbo]

Re: plugs:surface vs standard

The surface gap plugs that came on my 84 115hp were 14 yrs old and still firing when I traded it in 1998. It was a Merc mind you.
My dads 1980 35hp rude also had both surface and regular plugs speced for it. The manual said to use the conventional plugs if you did a lot of trolling and to use the surface gap if you mainly ran at WOT. Surface gap plugs are very cold and due tend to foul and therefore need a good CD type ignition to keep firing.

 

[david_r]

Re: plugs:surface vs standard

i put around a lot so i think ill stick with a little hotter plug. i carry an extra set but i dont really want to change them unless i have to especially on the water.

there nothing like dropping a tool in the water, espicially when your using it.

good to know about the longevity though i might have to switch my small motors to the surface gap, they're either wide open or off.

thanks for the help and info!