Spark Plugs (actual boating post)
 

I just bought a bulk pack of spark plugs on Ebay for a fraction of what
I'd have to pay anywhere else. They have no name on them, but they're
supposed to be Champion-made equivalents to RJ8C plugs. They look like
Champions, and they definitely look new. I bought them for my 1952 Case
SC farm tractor and some of my old Briggs-powered equipment, where they
should work just fine.

(This is the boating part) My Johnson outboards, a '54 10-horse and a
'64 9.5-horse, both call for J4-J plugs. The '64 needs new plugs
desperately, and while the '54's plugs look OK yet, they're getting some
age on them. You think these plugs would be close enough? I've used J8's
in these motors before under "emergency" conditions, but didn't leave
them in for long, so it isn't a case of whether they "fit" or not. I'm
wondering more about the long-term effects of the slightly higher heat
range.

BTW, these engines are used heavily for one week out of the year, in
fresh water. The rest of the time is mostly spent out of the water,
waiting for the next opportunity to go fishing. :-(

TJ

Spark Plugs (actual boating post)
 

On Sat, 14 Feb 2009 12:49:35 -0500, TJ wrote:

I just bought a bulk pack of spark plugs on Ebay for a fraction of what
I'd have to pay anywhere else. They have no name on them, but they're
supposed to be Champion-made equivalents to RJ8C plugs. They look like
Champions, and they definitely look new. I bought them for my 1952 Case
SC farm tractor and some of my old Briggs-powered equipment, where they
should work just fine.

(This is the boating part) My Johnson outboards, a '54 10-horse and a
'64 9.5-horse, both call for J4-J plugs. The '64 needs new plugs
desperately, and while the '54's plugs look OK yet, they're getting some
age on them. You think these plugs would be close enough? I've used J8's
in these motors before under "emergency" conditions, but didn't leave
them in for long, so it isn't a case of whether they "fit" or not. I'm
wondering more about the long-term effects of the slightly higher heat
range.

BTW, these engines are used heavily for one week out of the year, in
fresh water. The rest of the time is mostly spent out of the water,
waiting for the next opportunity to go fishing. :-(

Try what you have, and read them. The motors are not high powered and
a little bit of the wrong plug won't kill them. Get some platinum
points and be set for the next five thousand hours. We changed the
platinum plugs in the Navigator at 100 000 and they looked fine.
Should have run them til the check engine light came on, it takes two
hours to change. I miss the original flathead in the family runabout.

Casady