Question on spark plugs

I have a 2003 Kawasaki Voyager. The manual does not specify any
interval for actually replacing the plugs, it only says to inspect,
clean & adjust gap, or replace as necessary, every 5,000 km.

I'm pretty sure that I know when a plug needs replacing from the look
of it. However, something that has always concerned me is the plug
comes with a compression washer, and after it's been installed and
removed once, the washer is permanently compressed. I always worry
about re-tightening it again, and how much force to use. I'm scared of
stripping the threads.

Any guidelines on this would be appreciated.

Paul Harris

 

You *should* replace the washer and torque it to the manufacturers specified
setting - the torque setting will be in the workshop manual.

Q.

 

My experience is with cars, and recent models basically don't
touch the plugs for ages (I think my previous car, a Plymouth Laser RS
Turbo may have had one plug change in the 12 years I owned it -- 43K
miles).

A decent four-cycle engine probably doesn't need much checking
of plugs... OTOH, unless you've got a 6-cylinder engine, plugs aren't a
major cost factor on a motorcycle -- are they?

--

 

The torque spec in your book should be all you need. If done right each
time, there won't be any undue stresses on the threads to worry about. The
biggest enemy here is probably dirt between a crushed washer and the seat.
Some folks say replace the washers, but they never seem to mention where to
buy new ones without spark plugs already attached. Maybe I'll actually ask
for them next time I step into an auto parts store. I might be surprised.

 

I replaced the plugs on my 87 Voyager at 30,000 miles just because I
felt I should. They still looked fine and the bike didn't run any
better with the new plugs. I sold it at 46,000, but had I kept it
probably would have run the current set to at least 40,000. Pulling
them every 5,000 KM is also way overkill. I didn't touch mine until
15,000 miles and they still weren't all that bad. Closed the gap and
little and put them back in.


Matt

 

Thanks Matt, and others, for your comments.

PH

 

I have reused the compressed spark plug washer on my sleu of
motorcycles over the years without trouble. Use compressed air to
blow out the spark plug area before you remove the plug to get rid of
any debris and then blast the spark with compressed air around the
washer to remove any debris again. If you are worried about stripping
the threads be sure to use a small ratchet with a short lever arm (or
a small 3/8" torque wrench if youre really worried). I use a small
T-bar plug socket specifically meant for spark plugs and you have to
Hulk Hogan to do any damage with these.

 

Question on spark plugs

Group: rec.motorcycles.tech Date: Thu, Jul 15, 2004, 3:43pm (EDT-3)
From: (Paul Harris)

The use of unleaded fuel has made even standard spark plugs last a very
long time. 15,000km would be a more realistic milage to check the plugs.
(Or you could replace them with iridium plugs, which will outlast the
motor).

 

They lasted a long time on leaded......

 

Re: Question on spark plugs

Group: rec.motorcycles.tech Date: Mon, Jul 19, 2004, 10:05pm (EDT+5)
From: (The Older Gentleman)
The use of unleaded fuel has made even standard spark plugs last a very
long time.

True. Providing you occasionally sandblasted off the deposits caused by
leaded fuel.

 

What the *hell* are you on about? I don't know anyone who ever
sandblasted spark plugs. I doubt anyone has done it since the 1930s.....

Everyone cleans plugs from time to time, but that was to remove
carbon/oil or whatever......

Hell, I remember my Dad's old cars and I can't *ever*recall a spark plug
failure, nor him ever sandblasting them!

Mind you, if you're using webTV then your grasp of matters technical has
to be a bit shaky..........;-)

 

I used to have a cigarette-light-socket powered plug cleaner in
the early '80s... And used it too.

Of course, that 225 slant-six had a bad valve seal on #5, so
every three or four months I'd have clean that plug (or have my right
knee bashed by the shift lever from the miss during acceleration --
shift lever was physically mounted to the left side of the transmission,
not to the body centerline).

--

 

Fair enough - but that would be oil fouling due to the dodgy seal. Not
lead fouling, which exists only in the fevered brain of opietaylor.

 

I was only commenting on the use of sandblaster-type plug
cleaner in the 80s, not the cause of fouling (the Ghost of Chrysler was
already unleaded [bicentennial edition "Spirit of 76" Dodge Dart, A833
Overdrive-4, Hurst shifter positioned almost directly beneath the right
edge of the steering wheel -- a straight down drop got you the knob])
--

 

Oh yes, fair enough.

And a nice sounding car - I think......

 

Re: Question on spark plugs

Group: rec.motorcycles.tech Date: Tue, Jul 20, 2004, 7:20pm (EDT+5)
From: (The Older Gentleman)
Re: Question on spark plugs
Group: rec.motorcycles.tech Date: Mon, Jul 19, 2004, 10:05pm (EDT+5)
From: (The Older Gentleman)

Your cliche'd insults aside, if you are unaware that plugs stay much
cleaner due to unleaded fuel, then you might want to reappraise your
ability to post anything useful in a tech forum. If you've never heard
of bead blasting or sand blasting sparkplugs, you never worked in a
repair shop in the days of leaded gasoline. And lastly, if you don't
understand that lead deposits, on their own, could foul plugs, your
grasp of matters technical is non-existent. As for plugs "lasting", a
fouled plug can be brought back to servicability, and to a clueless
moron, that might mean that it "lasted".

 

Re: Question on spark plugs

Group: rec.motorcycles.tech Date: Tue, Jul 20, 2004, 7:20pm (EDT+5)
From: (The Older Gentleman)

"Whatever" huh? Now there's a technical term worth grasping. In
fact, with modern unleaded fuel, and modern (read platinum or iridium)
sparkplugs, the need to clean plugs is virtually eliminated, providing
the engine in question is operating properly. If your contention is,
that sparkplugs in "the good old days" lasted as long (particularly
with leaded fuel) as modern plugs using unleaded fuel, then you are so
inept on this subject, so delusional, so misinformed, and so
completely and totally wrong, that further discussion is pointless.
Get your head out of the sixties, and do a little research. (Maybe even
try some of these "new fangled" plugs. ps...if I'm shaky, you're an
earthquake..

 

Schizoid car... The Hurst shifter, bucket seats, and eagle
stripe down the sides made it look sporty. The high-torque/low-RPM
slant-six (only around 95HP, but 170ft-lb @ 1600RPM -- the fast idle was
at the torque peak!), overdrive transmission (take an early 60's muscle
car 4-speed, flip the 3-4 linkage so that "3rd" on the lever activates
"4th", replace "2nd" with a ratio that looks "2.5" and the former "3rd"
with an overdrive ratio), and a differential ratio in the 2.80 range
(combined with the overdrive, the top end ratio was down to 2.11:1)

{It was the last car that was simple enough for me to do the maintenance
on, hence all the details}
--

 

This from the man who is advising people to beware of lead fouling????

 

Look, please try and post in a comprehensivbel and/or readable fashion.
In other words, ditch the webTV shite (which really is, I'm sorry to
say, the posting medium of morons) and find *anything* else.

All I'm saying is that I'm old enough to have had 15 years' worth of
riding and driving experience before unleaded fuel became the norm, and
I have never, ever, ever had a plug foul due to lead deposits.

Not saying it's impossible - just IME so rare as to not to be worth
considering.

There are many, many more things that are more likely to foul plugs.

And I didn't say I'd never heard of sandblasting plugs - I just pointed
out that nobody I've ever heard of has done it for ages. Or didn't you
read the posting?

You aren't related to the late great Hoyt McKagen, are you?