08-05-2008, 09:27 AM #1
'94 701 waveraider eating spark plugsI bought this last year and it ran great, trouble free all summer. So far this summer about every 2 trips out it ruins a spark plug.Every time it's happened has been with someone else riding it so I can tell you exactly, but basically it's going fine then looses power. When I take it out after it's happened it runs ruff and won't go over 3.5-4k RPM(and has absolutely no punch getting up to that speed), basically what you'd expect from an engine running on 1 cylinder. However when riding it like this I can feel/hear the other cylinder fire occasionally.
First time it happened I wasn't sure what was wrong so I cleaned the connections and switched the plugs/wires and confirmed one of the plugs was dead, I replaced both plugs and it ran fine.
Second time it happened I jiggled the plug wires around and it ran OK but not perfect, I then replaced both plugs and it worked fine.
It happened a third time yesterday and messing with the plug wires did nothing. I suspect that as soon as I replace the plugs it will work fine.
What could be causing it to ruin plugs so fast? Only other thing is 2 of the times I could hear it pinging when my friend took off on it, then it blew the plugs a few minuted later.
Also what is the part number for the correct plugs and what should they be gapped to?
08-05-2008, 09:28 AM #2
need to test compression and find out if your problem is electrical or mechanical.
08-09-2008, 01:12 AM #3
i agree with the compression test, but are you gapping the plugs you put in?
08-20-2008, 12:41 PM #4
- Join Date
- Aug 2006
I believe you have an ignition coil problem, or that the ignition wire from the coil to plug is broken internally, or the plug cap is bad(shorted or not screwed on the wire good). That is not uncommon, and when the plug that has the weak spark doesn't fire all time, it gets carboned up and wet, then appears bad.
We had one bad coil which fired only 1 cyl (the coil fires both plugs at the same time, the one time is when the piston is at bottom so it is a wasted spark), you could put plugs on the wires and not installed so you can watch the spark when cranking, should be a sharp blue color spark on both. If you have a weak yellow spark, bad coil, wires, or cap.
On a Super Jet, we had a coil that appeared to be bad, but actually the ignition wire was broken about 2" out of where the wire comes out of the box. It wasn't damaged on the outside, but was burned in two inside the wire's jacket.
Our symtoms were exactly what you described.
NGK BR8HS at .024
Users Browsing this Thread
There are currently 1 users browsing this thread. (0 members and 1 guests)
By o0 RASTA 0o in forum Yamaha ClassifiedsReplies: 3Last Post: 07-18-2011, 03:19 PM
By MikeTrin in forum Sea Doo How To & FAQsReplies: 9Last Post: 01-23-2009, 05:16 PM
By Shibby1485 in forum 4-Tec PerformanceReplies: 5Last Post: 07-08-2005, 10:12 PM
By mgo7483 in forum 4-Tec PerformanceReplies: 33Last Post: 07-08-2005, 07:44 PM
By Cutter in forum 4-Tec PerformanceReplies: 6Last Post: 07-07-2005, 03:47 PM