mattrourke
Member
Also, is there supposed to be this much goopy oil in the rave?
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787 RFI low power
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Poormanracing
Active Member
Good info you have a voltage drop problem on a trailer there is no load on it but I bet if it's on the lake and bogs down you will see voltage drop as your going could be stat
No should be cleaner but will get goopy over time you may have a cyl going out you can pull that rave out and look at the piston skirt the voltage at wide open should be higher if you put a load on it and watch gauge I'm betting the voltage will be pulled down.but have a look inside cyl
mattrourke
Member
From what I can see in the cylinder (not much), it looks ok. I pulled the top of the rave off the good seadoo and it is also pretty goopy so I'm guessing they have never been cleaned... Ever.
Poormanracing
Active Member
If you look down rave valve hole you can spin the pto flywheel and see the piston make sure it doesn't look like scuffed up
I hooked a ground from battery negative terminal to the block and started my 3d on garden hose on trailer and there was no difference how engine ran still bogging just over idle. But was worth a try. Matt I am no expert but your compression does seem kinda low to me. My ski has 155psi on both cylinders. 135psi seems low. But I am no expert.
mattrourke
Member
Here is the volts on the water:
12.85 non run
12.77 lanyard
13.60 idle
13.98 WOT
14.14 minimal throttle
Poormanracing
Active Member
Is this a new ski to you or have you had it for a while and just started doing it.as far as compression goes gauges are different more oil in combustion chamber will give a high reading At our dealership none of us own a compression gauge useless toll.we do a leak down test.no body pulled the rotary cover off and installed valve in wrong.have you checked fuel pressure while running?if you have air box off you can carefully seal off the air opening to fake choking motor and see if bog goes away.that will tell you it's a lean big and fuel system is problem
mattrourke
Member
This ski is new to me so I don't know the full history. Is there a fuel pressure gauge that will quick connect to the fuel line or will I need to get creative? Are you suggesting take the air box off and choke it while on the water? No problem, just want to make sure.
When you say seal off airbox can a person use duck tape over screen or take screen out and d how much to start with half the are screen covers. Another great idea.
I used hose clamps and hay wire and a car fuel line tester. It worked. The plastic fitting on fuel rail just be careful not to over tighten and the metal one off top of tank is where I needed hay wire clamp to clamp to hold on it on. One mins test I only lost 10 psi so not to many leaks.
mattrourke
Member
So you tested pressure at the end of the hose before the fuel rail and then also directly out of the top of the fuel pump?
mattrourke
Member
Sorry I misunderstood. you just put it in line of the fuel line, put the lanyard on and it should hit around 60 and see how long it takes to leak down or do I actually run it for a bit and see what the pressure does?
Poormanracing
Active Member
Yes duct tape will work and t in a gauge any place even if you cut the fuel line you can put a Barb fitting back in it with some oetiker clamps and watch the gauge when it bogs see if pressure flutters.have you put a spark tester on to see if your loosing spark.and I believe there is a ground wire that plugs into the coil pack make sure that is good also
mattrourke
Member
I can get a spark tester like this and test it but I don't know that I will be able to see it at the lake. I can back the trailer into my shop and can watch it there but not sure if it will miss without a load.
Poormanracing
Active Member
You can see it under the seat at the lake if memory serves me right rfi idle on one cyl at random and when TPS starts to read a certain value and certain rpm the other cyl lights up
mattrourke
Member
This is the 3D model so I will have to get creative but I will definitely give it a shot. It might be worth it for me to switch the coil over from the other good seadoo to eliminate that as an issue too.
I used a spark tester light on my 3d and both cylinders seem to be getting a signal to fire. I also took mag spark plug wire off and 3d started and ran the same. So I took pto spark plug wire off and started and still ran the same. I am sure hoping my problem is Ecu I am running. Out of idea but will try covering intake next chance I get just to see what happens.
Poormanracing
Active Member
Yes it won't hurt to check off the basics did you swap ecu from the other machine and when you say bog does it work itself out and hit the rev limiter at wot on trailer.and when it is bogging does the engine rattle around.i keep for getting it's a 3 d and not a Gtx or gsx rfi
Poormanracing
Active Member
And do yourself a favor when your working search on you tube .722 it has a bog.worth a listen
I have not swapped ecu yet still waiting to receive it in the mail. The guy I bought it from has two 3d and swapped it between 3d to make sure it worked and it did he said. The bog doesn't work itself out. It almost seem like when you first start ski it will just not rev out like a rev limiter at 3000 rpms but the more you try it then it sounds like a bog. I am thinking that is caused because the motor is still getting the oil since it manual but not the fuel or spark to speed up so it loads up with oil or gets very rich then it sounds like a rich bog the longer it runs and does rattle around a bit the longer it runs. Thanks for the help. My history is mostly in dirt bikes/steertbike/sleds and this seadoo thing is new to me. But I can tune a 2 stroke single cylinder/carb dirt bike really good and can tell a lean or rich bog this seems like a rich bog. I have been wrong before haha
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