Thread: rxp engine rebuild and lost rpm
02-19-2012, 08:28 AM #1
rxp engine rebuild and lost rpm
i just rebuild my 04 rxp after dropping a valve. i replaced the head (serviced)and 1 piston replaced all bearings and piston rings,set cam fully retard after running it in for 3 hrs max rpm is 7700.
checked compression 145psi on all cylinder, checked prop and wearing all good.
can the low rpm be from a fresh tide engine??any 1 experience this after a fresh build?
02-19-2012, 08:57 AM #2
7700 is not terrible if running in hot weather
Has supercharger slip been checked at all?
02-19-2012, 09:01 AM #3
supercharger just got rebuilt as well..today temp was about 25deg C
02-19-2012, 11:26 AM #4
Is the setup in your signature where you were before? If so you are down 700 rpm? 145 psi at full retard is great, timing seems good, I would put on a boost gauge and check boost. If you have fresh gas and spark plugs, I would suspect the other usual suspects ... boost leak, exhaust leak, SC slip, leaking intercooler, leaking BOV.
02-19-2012, 04:57 PM #5
02-19-2012, 06:22 PM #6
What speed is it running at 7700rpm?
02-19-2012, 06:45 PM #7
You need to check the slip on your S/C even if it was rebuild after couple of hours after use, also check that oil level is not overfill that also could robe you some RPM.
02-19-2012, 06:50 PM #8
145 PSI at full retard seems really high. Are you sure you dident advance it fully all the way? Mine at close to full retard is 120 PSI
02-19-2012, 06:58 PM #9
- Join Date
- Jul 2010
I found that my cam gear was off one tooth with the cam and crank lock in place and was getting the same problems when looking down at the cam gear from the back of the ski the hash marks had to be more clockwise and the cam trigger pin was almost inline with the cam sensor .... Hope this is not confusing ... As per the manual there are 2 possible ways for the cam gear to fit and the bolts should not bind or be tight on the cam gear and in my case both positions the bolts were loose
02-20-2012, 08:42 AM #10
at 7700rpm my speed is 109 kph on gps...
just checked the slip at its at 10nm also rechecked the cam setting and is correct and cam timing is on full retart.
i test the compression with 2 different gauge and both cam up with the same reading 145psi on all cylinder.
would this engine need more hours to loosen up?.
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