MacAddict
Active Member
Hey guys... first off, thank you very much for the forum and all the help that you've provided. Having read through the posts over the last 2 weeks has saved me infinite time and frustration. :thumbsup: Secondly, I apologize for how long this post got.
Okay... so I'm new to the forum, and new to Seadoos/PWC's, but not new to rebuilding engines (although mostly 4 stroke). Have rebuilt a number of motorcycles along with an inboard/outboard volvo.
Anyway... Picked up a pair of Seadoos on a double trailer - 2001 GTI (720) and 2001 XP (951), where both needed work, and both had been sitting for some time... always more work than expected, but so be it...
Brief history:
So okay... here's where my issue comes in... on the XP, the previous owner had done a hell of a jerry rigging on some of the electrical. At some point, they broke or lost the boot to the front spark plug, and decided that instead of buying a $10 replacement boot, that exposing the wire inside the spark plug wire and wrapping around the tip of the spark plug with some electrical tape was good enough.
Well.. given my OCD nature, this just wasn't going to work. Being as I had some left over 8mm silicone wire and 90 degree boots from the Volvo rebuild a few years ago, I decided to use a bit of that. Now, while the XP runs pretty well after all the work above, and I've got it dialed in really close I think (it's very responsive), there's a bit of 'roughness' to the sound of the engine up and down. Almost like it's misfiring... holding it @ any RPM, it will "pop" sporadically... not smooth... and revving it up, it pops even on the way down.
So okay... maybe I'm stoopid for not checking the manual before using aftermarket wires and boots, but are the resistance type boots and wires really necessary? I've not used them before on other engines... Would this cause the "popping" that's occurring? Or is that typically manifold/vacuum leaks or fuel delivery? I assume if the MPEM is expecting a certain resistance, this would cause issues. I am getting 9.5/9.8 ohms of resistance on both wires from the coil, which is within the 12 +/- 3.5ohms rating from the manual, although near the outside of that range. But I also get 0 resistance from the coil to ground, where the manual calls for .33-.6 ohms of resistance. I wonder if the jerry rigging popped the coil(s)?
Should I go back down to a 7mm wire (which specific resistive wire?) and pick up a pair of NGK TB05EMA 5ohm boots? I'm just trying to figure out if this popping/rough running is electrical or fuel/manifold/vacuum related. I assume I shouldn't water test until I get it smoothed out... I don't want it throwing a rod... or worse...
Again... thank you for all the help you have already provided, and my apologies for the long post. I just prefer to be descriptive. :thumbsup:
Okay... so I'm new to the forum, and new to Seadoos/PWC's, but not new to rebuilding engines (although mostly 4 stroke). Have rebuilt a number of motorcycles along with an inboard/outboard volvo.
Anyway... Picked up a pair of Seadoos on a double trailer - 2001 GTI (720) and 2001 XP (951), where both needed work, and both had been sitting for some time... always more work than expected, but so be it...
Brief history:
- 1st thing I did (per the guidance here) was yank the grey fuels lines from both and replaced, (full of bluish-green crap) which included cleaning out/soaking both fuel petcocks in some marvel oil and replacing all clamps with SS c-clamps.
- Second to that was to rebuild the carbs on both, keeping existing springs and used new manifold gaskets, which I've now completed, and have both engines running. Need to get both in the water to fully test/dial in under load, which will happen this weekend, PWC gods permitting.
- Converted the XP to premix, after a fiasco of the allen bolts on the oil pump breaking off in the block, then a screw extractor breaking off inside that.... :banghead: Fabricated an aluminum plate to fit over old broken off bolts with 2 new tool & died taps/SS bolts to hold in place, along with a little silicone. I cut and double-crimped the thin oil lines that used to feed up under the carburetors as well to prevent air intake.
- Removed and cleaned Reed valves (no chips or scratches to note)
- Fully cleaned RAVE valves back to chrome finish, checked bellows, replaced Orings and reinstalled, noting which cylinder they came from, beveled edge down. (again thanks to guidance from here)
- Cleaned and inspected water regulator valve/bellows on top of water box
- New plugs BR8ES on both, gapped to .20
So okay... here's where my issue comes in... on the XP, the previous owner had done a hell of a jerry rigging on some of the electrical. At some point, they broke or lost the boot to the front spark plug, and decided that instead of buying a $10 replacement boot, that exposing the wire inside the spark plug wire and wrapping around the tip of the spark plug with some electrical tape was good enough.
Well.. given my OCD nature, this just wasn't going to work. Being as I had some left over 8mm silicone wire and 90 degree boots from the Volvo rebuild a few years ago, I decided to use a bit of that. Now, while the XP runs pretty well after all the work above, and I've got it dialed in really close I think (it's very responsive), there's a bit of 'roughness' to the sound of the engine up and down. Almost like it's misfiring... holding it @ any RPM, it will "pop" sporadically... not smooth... and revving it up, it pops even on the way down.
So okay... maybe I'm stoopid for not checking the manual before using aftermarket wires and boots, but are the resistance type boots and wires really necessary? I've not used them before on other engines... Would this cause the "popping" that's occurring? Or is that typically manifold/vacuum leaks or fuel delivery? I assume if the MPEM is expecting a certain resistance, this would cause issues. I am getting 9.5/9.8 ohms of resistance on both wires from the coil, which is within the 12 +/- 3.5ohms rating from the manual, although near the outside of that range. But I also get 0 resistance from the coil to ground, where the manual calls for .33-.6 ohms of resistance. I wonder if the jerry rigging popped the coil(s)?
Should I go back down to a 7mm wire (which specific resistive wire?) and pick up a pair of NGK TB05EMA 5ohm boots? I'm just trying to figure out if this popping/rough running is electrical or fuel/manifold/vacuum related. I assume I shouldn't water test until I get it smoothed out... I don't want it throwing a rod... or worse...
Again... thank you for all the help you have already provided, and my apologies for the long post. I just prefer to be descriptive. :thumbsup:
