Author Topic: Odd spark plaug behaviorwith my FZR  (Read 1200 times)

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Offline DavePhipps

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Odd spark plaug behaviorwith my FZR
« on: January 10, 2012, 04:03:16 PM »
Here's a bit of oddness. My FZR died one morning. I checked the plugs and they looked decent but there was no spark. Just as a control I put an old slightly fouled plug from my 550 in the boot and got tons of spark. Can plugs just die? All 4 of them at one time? Seems odd to me.
My test was with the electrode touching the engine.I made sure I used the same spot for both types of plugs and repeated the test 3 times with the same results.
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Online grcamna2

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Re: Odd spark plaug behaviorwith my FZR
« Reply #1 on: January 11, 2012, 09:44:21 PM »
Hi DavePhipps  :D,
         I have worked on a couple FZR's that had a problem with the spark plug caps, they fit way down into a recessed well into the cylinder head.I have found water gets down into those spark plug hole "wells" and just doesn't seem to evaporate too easily & that causes problems with the actual spark plug caps themselves...they do get cracked inside after they fill with corrosion and then they short out inside those "wells" and the spark shorts out directly to the inside of the aluminum sides of the spark plug holes.I have replaced them before w/ some NGK generic spark plug caps(they're a lot cheaper than the Yamaha parts) and that fixed the problem.I recommend you get the best quality caps you can afford(Yamaha if possible;they last the longest) & replace all 4 of them and then clean out all the water drain holes in each one of those spark plug "wells" on all 4 cylinders;I think there are 2 drain holes right next to each spark plug down there.When you're done,spray down all the insides of the spark plug "wells" with WD40 or equivalent(don't let the spray get down into the engine..keep the plugs in for that part of it) and then blow out each spark plug "well" with compressed air until all the drain holes are cleaned out.I recommend you do this very carefully & make sure you get all of the surfaces as good and clean as possible...what ever you don't clean out will fall down into your spark plug opening when you change your plugs and will then get into your engine; use a vacuum cleaner on each one is a good idea.

                        Get back to us and tells us all here how that worked out ;).
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