09-01-2013, 10:25 PM #1
Ultra 300x Can get above 7300 RPM with SCOM
Hey guys looking for some help
I have 2 Ultras 1 for me and 1 for my son - (2011) Mine has 15 hours on it and his has 12 hours. I thought I had some bad gas from a fill up a few weeks back, however now I don't think that is the problem. My ski also has a hesitation or a blip feeling when I slowly pull the throttle through it's throttle range from half throttle to full - the best way to describe it is like a spongy throttle - from a whole shot it pulls and goes like it should, however when just fooling around, I don't have that same instant throttle response lime my son's ski-
I thought I might have gotten some questionable gas a few tanks ago, however my son's ski has has the same gas and we are now 2 tanks after that incident - so both skis have new gas, 91 octane - no ethanol.
I also installed a SCOM and I can not get over 7400 RPM - WOT I get 67 MPH and 7250 - 7270 RPM, I was racing my son today to test mine against his and he slowly started to slowly walk away from me and his speedo topped out at 65 @ 7360 RPM -
Do you guys and any ideas what could be the issue (ski still under factory warranty) - I should be getting RPM's over 7300 - I know the speedos are not exact, however with SCOM my son's stock 300 should not walk away from my ski with SCOM installed - by the way this is my second SCOM - R&D sent me another one when I could not get over 7300 RPM with the first SCOM installed.
Could it be the impeller?, I have a few very small dings, I can barely see them - 1 very very small kinda ding and maybe 2 small blemishes - what about the S/C belt. Could it be the s/c belt slipping?
all hoses look connected and I take really good care of these skis
Last edited by John Arnaut; 09-02-2013 at 04:01 AM.
09-01-2013, 10:28 PM #2
put the scom on your sons and see if it makes a difference. im guessing 100% faulty scom or installation.
09-03-2013, 12:20 AM #3
Great idea - I don't know why I did not think of that. I went to try to install the SCOM into my son's ski today and I could not get the brown wire with the white stripe out of the connector (I did have the connector lock - unlocked) it was in there too good, wouldn't budge - I started to mar the wire a little, so I thought I should stop and not go any further. I will call R &D tomorrow about the SCOM
I was looking at something else and wanted to know what you think - It is possible I got a little anti corrosive spray on the S/C belt tension pulley when I was spraying the metal components after a ride. If I got a little on the pulley, do you think it could cause a little slip and this is the spongy feeling I get when I pull the throttle - maybe the belt is slipping a little. I think the pulley is on the top of the belt, so I am not sure if a little lube spray could make my ski lose the instant throttle response like I use to have and my son's ski still has.
And do you think it is possible to get (2) SCOM units that are faulty?
09-03-2013, 05:39 AM #4
belt slippage due to lubricant overuse burns off and dries out the first time it slips, im still betting scom either faulty or not seated correctly in the plug.
put in simple terms your sons ski should not be overtaking you with a scom fitted, so it points to it doesnt it?
09-04-2013, 05:31 AM #5
Well I called R&D today and spoke to Glenn -
He thought it might be the blow off value - so I switched the blow off valve from my sons ski to mine ski and it is still doing the same thing - I still can't get over 7300 RPM (with SCOM installed) - and I still have a little blib of hesitation at about 5500-6000 RPM - this is so frustrating - I guess it is off to the dealer
09-04-2013, 05:38 AM #6
09-04-2013, 06:02 AM #7
09-04-2013, 09:52 PM #8
Hey guys -
I think I have some clues, please let me know what you guys think -
SCOM defiantly works - I took the SCOM off of my ski and put in on my son's skis and tested it today - his ski got up to 67 on speedo, RPM 7550 - 7640 - first time (I know speedo is not accurate), his ski has always topped out before at 65 - 66 and about 7380 - 7400 RPM - (I had it set neutral trim or 1 point up) glass lake - very very mild chop if any, maybe ripples - so it looks like the SCOM Works
Yesterday when I called R&D and I spoke to Glenn, he suggested that the issue might be my VALVE-ASSY-RELIEF,BLOW OFF (part # 16130-3707) so after switching that part from my son's ski to mine. I still had the hesitating and spongy throttle and my son's ski still working fine, so it can't be that. - I also switched out the VALVE-ASSY-RELIEF,AIR BYPASS (part # 16130-3703) and at first it seemed that I had the same hesitation issue and then about few minutes of running around on the lake, it started to run pretty much perfect - no hesitation, instant throttle response like it is suppose to. So I also took my son's ski out and tested it with the part switched out and his still ran like brand new - no hesitation, so I am not sure what is going on.
Also the weird thing, and I think this is the clue is my ski had over a half of a tank of gas in it and it sucked it down to 1 bar left on the gas gauge in about 20-30 minutes of me testing my ski with the part switch. the fuel buzzer did not go off and I did not notice I was even getting low on fuel until I got home and put it on the hose to flush out - all of a sudden the buzzer goes off an the fuel bar has 1 bar - weird) - so did I change any thing with the fuel management system by changing these parts out with my son's ski - his still has 3/4 of a tank like I started with and I had his ski out a little longer and WOT to check the SCOM
So I think this entire time I am having a problem with my fuel system or something like that - maybe that is why I can't get the SCOM to work on my ski (however I have not tested the SCOM on my ski with the parts swap yet)
also please note one other thing - not sure if it matters, however bringing it up. When I first bought the ski a few months ago I tried to put anti seize on the spark plugs and use the wrong torque wrench and broke off 2 spark plugs in the head - took it to the dealer and I lucked out and I did not ruin the head - the spark plugs just broke off, so dealer took of the head to took out the broken spark plugs and install new ones and said everything looked good and there were no problems - do you think the valves got miss alined of something like that is keeping me from getting over 7300 RPM on my ski with the SCOM - I am maxing out at (speedo 67) RPM 7240 with and with out the SCOM - I think it is a fuel management issue
sorry for the long post
09-04-2013, 10:10 PM #9
the alarm will sound depending how the ski is sitting at the time. i dont believe you have a fuel problem.
personally i would now check (since you have just gave the extra info) engine timing (could be a tooth out) but first you have checked all boost hose related clamps havent you?
could also be a leaking blow off valve the one pictured on the R but you said you swapped it out also.
are you 100% positive you installed the scom correctly on your ski?
do yourself a favour and also test with a gps this will give you the most accurate info, (use a phone app if you dont have one)
failing this take it back to the dealer and explain the ski hasnt been 100% since they removed the head.
09-04-2013, 10:30 PM #10
- Join Date
- Jan 2009
It's always the extra info hiding there somewhere.
As mentioned timing could be off.
What boost are you getting at wot
What max speed are you getting at wot
What rpm are you getting at Wot
Have you checked to make sure the throttle valve is opening fully at wot
Have you installed new spark plugs
Have you pulled your intercooler and checked for sludge ?
Have you checked to make sure your exh filter is still there ?
Do all the above and report back
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