02 RXDI no start-please help!

[Mr. G]

Hi i am new to the DI skis and need help bad but i will try to keep it short. Bought an 02 RXDI that has been sitting since 05 with only 50 hours but crank was wiped out. Rebuilt the engine and the ski ran good but would usually start hard (hit the button and it would pop for a second and die) about 5-10 times and then it would idle and run good until you backed off the throttle it would die but you could restart it right away. Ski would foul out plugs and they would be really black but after changing them it ran great. today i had it out wide open for about 2 minutes and it ran about 6750 rpm but a little funky so i pulled over and it died. changed the plugs (which werent black this time, nice tan inside like they should be!) and it wouldnt restart, just pop for a split second and thats it. Felt like it wanted to but didnt. Fuel pump runs and sounds strong, has spark, plugs out fuel is spraying from injectors etc. I know cars very well (especially injection) but am new to DI seadoos. I am thinking about checking the fuel pressure tomorrow and am not sure what it should be (i heard around 90 psi?) could the funny starting and running issue i had before have gotten worse and now it wont start at all? rave valves are closed, compression is good, no funny beeps, only if i hold the throttle while cranking which i believe is normal. Battery and solenoid are new, new key D.E.S.S. from seadoo etc. Hopefully someone can help lead me in a direction since i want to ride it again. I thought about bringing it to have the ecm scanned, but i unplugged many things trying to diagnose it and am afraid of false codes. thanks in advance

Greg

 

[Mr. G]

can someone please help me out?!

o.k. i did a compression check and only got 90 lbs on both cylinders which seemed pretty low. the machine had a fresh bore and new pistons with only 3 hours on them. so i pulled off the head and the bores had very minor scuffs marks in the cross hatched marks and the piston to cylinder clearance was .016"! i dont know why, maybe oil pump konked out and didnt give enough oil? both cylinders look the same and have the same play but the pistons dont look melted or anything. i dont know getting frustrated but i love the machine. any ideas??? please help

 

[pickle8486]

i am interested in your post let me know what you found, i have an 04 xp with the 951 di that 3 weeks ago was tested and ok'ed by a certified seadoo mechanic and the engine had 140 psi in both cylinders so the print out states. i just checked today with my own compression tester and only got 90 psi in both cylinders with less tha 30 min of run time on the complete engine rebuild, i am using seadoo synthetic with added oil in the gas for break in and of course didnt ever excede 3/4 throttle.

 

[pickle8486]

make sure to open the throttle as you crank it over, thats what i was doing wrong, i got 135-140 lbs of cojmpression now.

 

[magical]

if you hold throttle while cranking it puts ski in drowned mode and stops fuel going to engine had a similar problem with my ski with plugs fouling and it was down to a faulty fuel pressure regulator

 

[NapaMatt]

Check Fuel Filter..

AND Check Fuel Pressure When Running TOO!!


My .o2

 

[Mr. G]

do you guys think that 90 psi only is enough to make it start. seems awful low to me me friends 951 makes 130 psi. im out of ideas so i ordered a new set of sbt pistons and am going to try it. .016" seems way to excessive of piston to cylinder clearance. if thats not it im not sure what else could make it sputter a little like that when trying to start.

 

[Mr. G]

ok, change of events here. i have ruled out that the air pressure is low and when i apply shop air the ski runs great. replaced piston, rings and sleeeve for the air compressor and it is still low on pressure. could it be in the reeds? they looked fine but thats all thats left on the air compressor piston. hate to keep throwing parts so help would be nice. thank you

 

[JACKOMO]

Did the machinist know what the clearance was supposed to be? It should be .004. What is your clearance on your second set? The piston kit normally has a sheet with clearance specs in it.