it runs but not in the water

[porkncheese]

Hi guys. My 96xp runs well out of the water but when its in the lake it bogs down and doesn't want to rev.
I have cleaned the carbs, checked compression and spark which are ok.
Any suggestions would be much appreciated

 

[Seadoobuddy]

What are the compression numbers? Should be 150.
What brand of gauge did you use?

very important: is your Battery good and charged up 100%???

 

[LouDoo]

Have you eliminated the fuel delivery problems? I believe from your previous posts that you may have a clogged fuel control valve, have you tried by-passing it?

As SDB said what are your compression numbers?

If everything checks out the next place I would look is the rectifier/voltage regulator. For testing disconnect the red lead from the rectifier, if your problem clears up, replace the rectifier. The rectifier/voltage regulator is located in the front E-box.

Lou

 

[porkncheese]

The battery is well charged and reads 13.9v. The brand of gauge I used was "Stanley" and the readings I got were just under 150. I triple checked it to make sure.
How would I go about bypassing the fuel selector for testing?

 

[LouDoo]

There's a couple of ways to bypass the fuel selector valve. You can remove the valve, find the hose connected to the res. connection on the valve and connect it directly to the fuel filter/water separator. Or you can run a fuel hose directly from the fuel baffle, marked res. either to the fuel filter/water separator or to the fuel inlet on the mag. side carburetor.

Lou

 

[porkncheese]

Thanks Lou I will try that.
If the rotary valve was out would it show these symptoms?
Paul

 

[Minnetonka4me]

If the RV was screwed up it wouldnt even start, if its off a tooth it will backfire at higher rpms.

Again, Like I said in your last thread, if you didnt replace the needles and seats, or if you did and didnt check the pop off...it will never run right if it isnt holding pressure. Ive had brand new ones fail right out of the bag.

 

[porkncheese]

The carbs pop off at around 35psi

 

[porkncheese]

I have pulled out the fuel selector valve. It was ok but I cleaned it anyway.
So frustrating cos it runs well at home. Its not till I get in the water that I find it wont rev.
Plumbing the reserve line direct and testing the rectifier has to be done at the lake.
Anyway I think I have covered the whole fuel system...

 

[LouDoo]

Well, to tell you the truth it doesn't sound like a rectifier issue, a weak rectifier interferes with the MPEM and it will make your ski feel like it's missing or running on one cylinder. But we're running out of options and it's easy to check.

I'm not sure if this question has been asked. Did you clean the water separator/fuel filter, also the "O" ring in the base of the assembly?

Also check the check the check valve in the fuel tank vent.

Lou

 

[Coastiejoe]

What were your compression numbers?

 

[nick.bain]

When you say wont rev, Do you mean it wont go over a specific RPM or it will rev out but takes forever to get there??

 

[porkncheese]

it wont rev out at all.
im thinkin it may be the water flow regulator valve.
I will know in the next day or 2

 

[Minnetonka4me]

The pop off isnt as important (at least in this instance) as making sure it steadily holds 10-15 PSI for 45sec-1min.

From there I would do a direct temp line from the fuel pu to the carb.


Its not likely the water reg...that usually just messes with top end RPM; from your description I doubt it has anything to do with it, but it still needs to be checked to make sure it isnt a seperate issue that needs attention.

 

[Coastiejoe]

So again, did you do a compression test? If so, what were the numbers?

Your description sounds exactly like what happens when a motor has around 120-125 compression.

At around 120 psi they will run out of the water, sometimes they start in the water but they will not have any power or rev.

 

[porkncheese]

The compression was just below 150psi. I mentioned that in my first reply.

The pressure on the carbs popped off at about 35 and held at 15. I only held it at 15 for about 10 seconds so I mite redo it.

I mentioned the water reg because a friend told me this happened to his ski when the diaphragm inside it failed. Mine is working fine but.

I was planning on running the fuel direct when I go out on the lake to test it again.

Thanks guys. Im open to any suggestions atm

 

[porkncheese]

Is their a way to check if the cooling and exhaust systems hold pressure and don't leak?

 

[Minnetonka4me]

gotta seal everything up...but if i remember correctly...you said this thing ran just fine before you did the carbs/fuel lines...?

 

[griz400]

for sh**s and giggles, take the seat off and run it in the water, cause if you have an exhaust leak, it will bogg it down for sure -- gotta have air ....

 

[Minnetonka4me]

Good point...you can also open the gas cap and make sure you dont have a venting problem.

Not very probable, but possible.

 

[nick.bain]

I would also take a new set of plugs with ya. Is there some history here? You asked about the rotary valve. How did this problem present??

 

[SeadooMan8]

I think from what I know could be any of these problems-
A:Low compression
b: incorrect carb adjustments
c: Your needle valve is dirty
d: Gas or oil has water in it
e: your throttleI is stuck closed
f: your exhaust has excessive carbon build up
g: you have weak spark
h: maybe jet pump or impellar damage?

 

[fisko]

hi porkncheese I had the same problem turned out to be the rotary valve was out of tolerance, luckily I have friend who is a fitter&turner he machined the face to spec.i also had a oring that was 2.6mm he put in a 2.0 mm oring seal so that the face of the rotary valve cover was almost flush on the crank housing when tightened to spec 15lb if you need a new oring go to a farm machinery parts supplier they should have oring in lengths I used 500 mm of 2.0mm oring cut and superglue to size works great now.

fisko

 

[fisko]

double post sorry