Thread: lost a few RPMs...
10-29-2014, 09:02 AM #1
lost a few RPMs...
last time out i saw i was hitting 7900 rpms instead of 8020-8040 and saw 66mph as opposed to 68 which ive seen many times. (have not used a GPS yet just dash)
just changed the spark plugs out last night and they all looked pretty much the same. i would go so far as to say the 1st plug (near steering i dont know what to call that one) was a tad bit lighter than the other 2 but not by much.
i will crawl under the ski and see what i see on the prop and wear ring but is there anything else i can check?
she ran fine last time out idled fine. i can get pics of the plugs tonight.
10-29-2014, 09:12 AM #2
Look for brown tar like crud in the bottom of the intake hoses, either going out of the supercharger and to the IC or out of the IC depending on the year ski. If you see this stuff, you need to clean the intercooler and then either rebuild the supercharger or get the EGR out of the intake.
10-29-2014, 09:17 AM #3
ski is a 2012 with about 45 hrs on it. supercharger will be rebuilt within the next few months.
what is EGR?
10-29-2014, 09:56 AM #4
the more i think about it the more i think the 1st plug was a tanish brown and the 2nd and 3rd were black.
i only had the garage light when i changed them so i will have to look at them when i get home. could the 2nd and 3 plugs have fouled liked that when the wife flipped it?
10-29-2014, 10:47 AM #5
All three plugs should be white on any EFI motor. Black is a problem.
I called it EGR, but I guess it is really a crankcase vent. It is a rubber hose coming off the top back of the motor that is about 3/4" ID and goes to the big hose that is from the air filter big and goes into the center of the supercharger. What happens is if the motor has the oil even slightly overfilled, the oil goes out thru that 3/4" hose and then goes thru the blower. From there, it heads to the intercooler, mixes with humidity and turns to goo. That kills the intercooler efficiency. You owe all of this to the EPA.
10-29-2014, 11:31 AM #6
i know the oil is not overfilled as i checked that after the ski was flipped and it was clean and right in the middle of the dipstick. same place it was when i bought the ski.
i will pull that hose and see if anything is in there. i will also post pics of the plugs and maybe they will tell you or someone else what could be going on.
worst case i take it to rogue racing since he is local to me if its something i cant do on my own. which honestly i just dont have the tools to really do any work on it.
10-29-2014, 12:04 PM #7
10-29-2014, 12:14 PM #8
Is it safe to just put one of those little filters on the egr and just vent it inside the hull or do you have to get a catch can?
10-29-2014, 12:52 PM #9
10-29-2014, 01:58 PM #10
the setup whittlebeast has is perfect. just make sure the catch can is slightly lower than the tops-valve so the access oil/fuel does not go back inside motor.
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