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Terrible vacation with my doo

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TPS - I'm inclined to agree but if all you did was adjust idle and not change the TPS position itself then I'm only in 70% (b/c I want to encourage you to work the bugs out).

Black plugs sounds like fuel soot to me though, and the mapping to largest degree is TPS, and manifold pressure, then temp.

Hard crank - I'm betting your starter is tired, dunno if it's already new though. If you were in salt then I'd also say your cables are toast.
 
starter is a oem denso and checked the brushes and armature during rebuild. brushes were like 80% good. replaced battery cables as well. it seems to crank like it should. i think the tps is off causing the plugs to get a bit to wet to fire and start. as i said in a previous post i had the throttle cable a little to tight and when i loosened the idle screw and the the throttle cable the throttle butterfly closed to little bit more so it wasn't closed all the way when the tps was reset. at the time i or the tech didn't think about that. it was when i checked the rv when it came to mind about checking throttle cable adjustment. when i adjusted it before during rebuild, i just made sure it was closing all the way to the idle screw and at wot open all the way.
 
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i want to take the time to thank every one who replied, especially ragtop and sportster whom hung in there with me an entire evening last week helping me trouble shoot my ski, ragtop pointed me to the raves and turned out the new bellows were too stiff for the springs to hold the raves closed. that took care of the horrible bogging issue and it ran perfect while it was running. candoo is on the way and will reset the tps which hopefully and am sure it will solve the starting issue in time for my next camping trip. thanks again to the world's greatest seadoo forum!:)
 
Spundslike the one cylinder the rings are lapping in and sealing. So now I wonder what Tom at SES was trying to say when he told you he shoots for 140psi..... Ah, so hard to nail this stuff down and too easy to jump to conclusions.
 
I Personally haven't seen more than a 3-5 LBS of static pressure change after a complete break in.
For me, I find fresh engines will usually read full compression because of all the excessive oil during assembly. After the first hour or so, a slight drop, & after break in it comes back. But 10 PSI is a big jump! I wonder if the higher cylinder had excessive fuel or oil at the time? Was it in flood mode, or injectors unplugged? If the plugs are wet, so is everything else in the cylinder.... Just a thought.

I think to get an accurate reading, the engine has to be driven & running normal at the time. Then let the engine cool for 12+ hours & check it. Just my $1 - $.098
 
i had the plugs out for a day before rechecking but who knows, i'm not too worried about compression as it is for know as i need more hrs on it cant wait till my candoo gets here hopefully by the week end.
the reason i rechecked the compression was because the way it died on me after the first couple minutes of riding. took the video scope to the cyl jugs to make sure no damage even though it ran great after it died.
 
No. The compression will not go up. I talked to SES. He said he has brand new seadoo motors and they are from the factory at 140 psi. 787s and 720s. I told him I had always seen 150 psi on both as he kinda scoffed at me. He said 150 would require race gas or premium at minimum to keep from pinging. 140 is what an SES engine will come from and he said that is because of the stroke ratio
 
No. The compression will not go up. I talked to SES. He said he has brand new seadoo motors and they are from the factory at 140 psi. 787s and 720s. I told him I had always seen 150 psi on both as he kinda scoffed at me. He said 150 would require race gas or premium at minimum to keep from pinging. 140 is what an SES engine will come from and he said that is because of the stroke ratio

Geeze, Why do we keep hearing this? is SES using a harbor freight compression gauge. ;) It's common knowledge that a healthy 580, 650, 720, & 800 will yield 150psi each side, every time. I don't mean to throw darts because this is second hand information to me, but 140 is absolutley NOT normal for a seadoo RV engine. 130-135 for a 951 & 140-145 for a DI, the rest of them are 150. End of story.... :D
 
i have a lang compression gauge:D
i think the pto cylinder likes me:D
yep that's what he told me 140 psi:rolleyes: need to ck my manual.
 
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The compression is not in the manual.

i can say though that I have 5 787 skis and they range from 145 to 160 psi, no race fuel used and one of them is an SES rebuild which was 152 psi 2 weeks ago.
 
Both my gauges have a standard air line connector that fit into my air line. I can pop it in the line & compare it to the gauge on my regulator which is a sharpe. Easy way to make sure the gauge is right, & if you have the correct long reach threaded adapter for the plug hole with the check valve in the very end, you should be golden. I don't like the gauge sets that have a one fits all hose & cheater adapters. those add a small amount of volume to the combustion chamber & can give you a lower than real reading.
 
Let's all take pictures of our compression guages with readings and randomly email them to him.... Seems like the only way he'll believe it
 
I guess compression results are important to me b/c if I see one that's blowing 140 I'm gonna think it's worn some when it might've just been rebuilt and is perfect inside.

I agree completely. Like checking the pressure in a car tire. If you find its at 22Lbs, your going to assume it has a leak.
 
i still find it strange that my pto reads 150 psi and mag 140. and i triple checked both of them. is it possible that the pto seated quicker than the mag side? just a couple weeks ago they were both at 140. my plugs i believe were slightly fuel fouled just enough to not fire right and no excessive oil at all. i even turned it over for a bit to see if there as excessive fuel and nothing. like i said im not going to worry too much till i get a few more hours on it and will recheck it before i bed it down.
kinda weird though the compression spec aren't in the manual. my question is that how can you warranty a engine for 140 psi to a re builder that swears it is ok. btw my candoo will be here tomorrow.
ragtop, my gauge is like yours with a quick release fitting with the valve core on the end of the hose. i used the deep reach, deep like my spark plug and is an expensive gauge.
 
Can't wait to hear how the Candoo works out for you. I am sure that you're so close to finding the issues. What a pain but I give you much credit for your patience. Hang in there Kevin.
 
got the candoo pro a few days ago so today i reset the tps after loosening the idle screw and cable to make sure the throttle body butterfly was completely closed. too busy to try it out till next weekend so i'll post results when i get back.

the candoo is very easy to use and have it linked to my windows 7 laptop. already erased a dess key that i dont have so it now only has 1 key programed to the ski but will buy spare one someday soon.
also wrote my name to the mpem as well. checked for fault codes and there are none. no more trips to the stealer! yay!
 
thanks guys, yea the suspense is killing me too! i'm really hoping this is all and be able to concentrate on having fun for a change. will be out of town camping for 5 days and hopefully will be able to have a good closure and good results.
i say this because it seems that while reading and searching forums with similar issues, the thread abruptly ends with no results and leaves us hanging.:banghead::D
 
HI
I have a candoo and same ski. What I did if it helps. Back screw out all the way till throttle no longer hits is. On the candoo it should read tps around 4.2-4.4ish area (this is zero). Than reset the tps and clear all faults. Also I go top left hand corner and "write" to mpem. (I don't think you have to but I did anyway.) That's it at that point with the candoo. Go to the ski and turn the screw in about 3 full revolutions. Now put ski on hose and adjust idle ( I did 2900 out of water on mine). In water idle says 1400 +/- 100. The idle you will have to screw around with. On mine I had to juice up the out of water to 2900 to get an in water idle initially of 1750. Now the ski after a few rides is out of water 2400ish and in 1550ish. I think the mpem adjusts it after a while but unsure. Anyway good luck, this worked for me. Also sometimes the candoo reads the tps as -4.4. If you see this it is probably because it timed out. I would "read the dess " again.
 
HI
I have a candoo and same ski. What I did if it helps. Back screw out all the way till throttle no longer hits is. On the candoo it should read tps around 4.2-4.4ish area (this is zero). Than reset the tps and clear all faults. Also I go top left hand corner and "write" to mpem. (I don't think you have to but I did anyway.) That's it at that point with the candoo. Go to the ski and turn the screw in about 3 full revolutions. Now put ski on hose and adjust idle ( I did 2900 out of water on mine). In water idle says 1400 +/- 100. The idle you will have to screw around with. On mine I had to juice up the out of water to 2900 to get an in water idle initially of 1750. Now the ski after a few rides is out of water 2400ish and in 1550ish. I think the mpem adjusts it after a while but unsure. Anyway good luck, this worked for me. Also sometimes the candoo reads the tps as -4.4. If you see this it is probably because it timed out. I would "read the dess " again.
i read your thread in the candoo forum mine also resets a 3 degrees. ended up turning the idle screw back in to 9.4 degrees which idles 2300 rpm on trailer and should be in the ball park of 15 to 1700 rpm and will fine tune it once in the water after riding it for a while. so how is your ski running now? starting easy?
yes mine read -4.4 a couple time and think it was like you said timed out. i would log out of the program and log back in and hook the candoo up and read 3.0 again. i'm so glad i got the candoo so that i can do everything myself and not have to rely on the stealer.
 
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