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Terrible vacation with my doo

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well i think i'm on to something, i tried ohm check my fuel injectors from the amp4 plug from the mpem and seems to be a short circuit!? on both injectors. should be 2.3-2.5 ohms. so i unplug the injectors and test again at the amp plug from the mpem and no short. so i ohm test on the pins directly on the injectors, short circuit. so if i am correct my harness is ok and the injectors are shorting out.
it is as if i am touching the 2 leads from the ohm meter together. 0.00! i even tried to ohm test another sensor and read perfectly as i did this to make sure my meter isn't messing up on me. would my ski run at all if my injectors were shorted? if so, probably why it's bogging badly at take off?

griz, kicker or PGHMAN, would you be willing to test yours and let me know what you get. test at amp plug 4, pins 18 and 20 injector no 1 and pins 19 and 21 injector no 2. thanks guys.
 
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Jammin, what meter are you using & setting is it on? Some of the multimeters that are not automatic have to be set on the lowest setting or they can see low resistances as a short. While they are not the same as your injectors The DI injectors I have here are between 2.0-2.4 ohm coils.

Just to see if your meter is reading low resistances correctly, unplug your R/R & ohm out two of the leads from your stator. should be around 1ohm maybe less.
 
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its a cheap cornwell and is set a 20k . i tried the other settings and reads the same. yikes maybe im missing something. lol i know nothing about ohm meters. i will get another one tonight and recheck.
 
you need something that has a range that caps a setting at 200 ohms, 200K is way to high. to read lower resistances.

I have a fuel injector pulse tester you could borrow to compare your injectors if you wanted. It won't tell you if they flow the correct amount of fuel, but it can compare the two of them to see if they are similar. you just plug it into the injector, bring the fuel rail to pressure & it provides a predetermined amount of calculated pulses. Then you read how much your fuel pressure drops in the rail. If one injector is plugged up or not working correctly, that injector won't dump as much fuel pressure during the test. Its really a troubleshooting tool, & nothing more. I bought it for automotive use, but it works on these injectors too.

I could send it to you to borrow, but we will probably have $25 spent on shipping both ways?
 
The injector resistance will be quite low normally, electrically they are most likely in good condition. It's the debris that can be trapped inside them that usually causes issues if any.
 
its a cheap cornwell and is set a 20k . i tried the other settings and reads the same. yikes maybe im missing something. lol i know nothing about ohm meters. i will get another one tonight and recheck.

Yep, start on the lowest scale and move up from there. I don't really care for the autorange meters that much b/c I prefer setting the range myself(less confusing for me) and usually I know which range to anticipate anyway.
 
thanks ragtop, i will keep that in mind. i just bought a innovis auto ranging ohm meter and will ck again.
dang i was kinda hoping that was my issue to i can move on and be done with it lol! i'll keep you all posted.

these are new injectors

i also pulled the mpem and opened it up to get to the bosch fuel management computer to have a look at the connector pins and all looks good, did that to eliminate all possibilities. i'm really running out of ideas except to take her camping with me to test the fuel pressure and volts while on the water.
 
Yep, start on the lowest scale and move up from there. I don't really care for the autorange meters that much b/c I prefer setting the range myself(less confusing for me) and usually I know which range to anticipate anyway.
i tried them all same result. but will try it all again with the new meter i bought. thanks.
 
I would still be pulling the RV cover to make sure its the correct one & timed correct. Costs nothing to check it. just a little time & a few drops of locktite. From the looks of the RV chart that was posted, it looks like there were not many different valves used.
Who knows, maybe somebody times it for a carb'd ski, or worse yet timed it with the PTO piston at TDC instead of the MAG?

Again, I am thinking that SES has a process to eliminate a mistake like that, BUT, RV issues can cause your symptoms.

[MENTION=2932]sportster[/MENTION], do you have that PDF drawing of the printable timing wheel he can print out?
 
I would still be pulling the RV cover to make sure its the correct one & timed correct. Costs nothing to check it. just a little time & a few drops of locktite. From the looks of the RV chart that was posted, it looks like there were not many different valves used.
Who knows, maybe somebody times it for a carb'd ski, or worse yet timed it with the PTO piston at TDC instead of the MAG?

Again, I am thinking that SES has a process to eliminate a mistake like that, BUT, RV issues can cause your symptoms.

[MENTION=2932]sportster[/MENTION], do you have that PDF drawing of the printable timing wheel he can print out?
yep i agree and as soon as i get back from the trip i will have time to ck on the rv for sure, out of time for now thanks. im only going to ride it for testing only this weekend.
 
i just talked to tom from ses and gave him the lowdown on how my ski has been running and he said he highly doubts that its a rotary issue but is ok to ck it if it would make me feel better. he seems to be very sure of himself. must have very strict quality control. i am also aware we are all human lol.he says he cuts his own rotary valves to be more precise timing that stock and Will be slightly different than factory specs. he told me to call him when i get the readings and he will help from there. just relaying how the conversation went. he said quite possibly a tps issue. told him had that reset. this is why i chose to be a under car tech lol!
 
I really don't like the fact that he cuts his own rotary valves. What is wrong with OEM valves, do seadoo engineers really not know what they are doing?? Doubt it. I talked to him yesterday also, he told me 720 engines put out 140 psi stock and same with 787s and if they ran 150 compression that they would require race fuel or at minimum 91 or 93. I told him every one I have owned pumped out 150 psi and he seemed shocked at this revelation. Not trying to start a war, but these were my findings. I'm sending an engine to him for warranty work tomorrow.
 
I really don't like the fact that he cuts his own rotary valves. What is wrong with OEM valves, do seadoo engineers really not know what they are doing?? Doubt it. I talked to him yesterday also, he told me 720 engines put out 140 psi stock and same with 787s and if they ran 150 compression that they would require race fuel or at minimum 91 or 93. I told him every one I have owned pumped out 150 psi and he seemed shocked at this revelation. Not trying to start a war, but these were my findings. I'm sending an engine to him for warranty work tomorrow.
wow he said the same to me on my rfi being 140 psi is perfect but others are pumping 150psi. WTH! thanks for the reply. not sure what to think now but you raise some good points on factory rotary valves as well as compression. i wonder if i should go a factory rotary??
wheres the best place to buy a rotary valve? is sbt any good or stay with oem?

id like to know what happened to your 720
 
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i just talked to tom from ses and gave him the lowdown on how my ski has been running and he said he highly doubts that its a rotary issue but is ok to ck it if it would make me feel better. he seems to be very sure of himself. must have very strict quality control. i am also aware we are all human lol.he says he cuts his own rotary valves to be more precise timing that stock and Will be slightly different than factory specs. he told me to call him when i get the readings and he will help from there. just relaying how the conversation went. he said quite possibly a tps issue. told him had that reset. this is why i chose to be a under car tech lol!

I'm quite sure I've read threads here about SES RV's not being setup correctly, I could be wrong though b/c often threads die out and honestly there's something about RV's that gives me shivers, no idea why, mine used to run so well but can't put a finger on my phobia.
 
update, with the new meter my injectors ohm out good soooo on to rotary valve. ski is staying home this weekend:( will get to it first of next week.
 
I'm quite sure I've read threads here about SES RV's not being setup correctly, I could be wrong though b/c often threads die out and honestly there's something about RV's that gives me shivers, no idea why, mine used to run so well but can't put a finger on my phobia.
yep im suspicious on the rotary valve too as makes his own timed differently. so i plan on buying an oem one.
cant think of anything else it can be. ive combed it all with a fine tooth comb! at least i think i did. lol
 
yep im suspicious on the rotary valve too as makes his own timed differently. so i plan on buying an oem one.
cant think of anything else it can be. ive combed it all with a fine tooth comb! at least i think i did. lol

Induction timing is super important when it comes to fuel injection b/c you have no ability to fatten up by adjusting jets and other carb tuning tricks that might compensate since everything's so precisely etched in silicon stone. The marine engines all run open loop on exhaust no O2 sensor(too wet for one) in these babies so the computer fuel mapping relies more heavily on the other sensors such as intake pressure.
 
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