Pop Off PSI

[Dfleming]

can anybody tell me what the "correct" PO for a '91 Waverunner with a 1.5 N&S? It is all stock? My repair manual doesn't say what it should be like the Sea Doo manual does, it just says what the PO should be for the diff. N&S and spring rate. I was told by the previous owner that the guy before him had it bored one size, that's all that's been done. I've rebult the carb, NEW N&S, new fuel lines, new filter, new selecter valve. The problem is it wont run at full throttle. does fine at 1/2 and below but when I open it up it hessitates and acts like it's not getting fuel. Sometimes it will clear up after a min or two and run fine but when I cut the throttle a little and then gas it again it's back to square one.

[torquenut]

Re: Pop Off PSI

Before you do anything read this thread, at least twice get to understand the different situations. Once you feel confidant, screw in the high and low side screws WHILE counting the number, record this and then you can reset them and go to the water. this way you will at least have a starting point. Good luck, here is the thread
http://greenhulk.net/forums/showthre...t=carb+tunning

[Dfleming]

Re: Pop Off PSI

And the high speed screw seems to have little to NO effect. The main jet is stock (115) I'm at a loss. It just doesn't seem to want to run at full throttle.

[torquenut]

Re: Pop Off PSI

OK so you have a 91 650 ski correct? and from what you are saying is that at full throtle is not developing all thr RPM's. Sorry I may seem simple but first check the buttery does it open all the way. If not then here is your problem the cable can be out of adjustment. If it is OK than you need to check your fuel pick up. Run it on reserve and normal any difference. One pickup may me plug or line has leak. If this check good, then you need to check the carbs.
Also what is the compression? take out the pulgs and if you can take a picture, I want to make sure you are not having a leak and running lean.

[Dfleming]

Re: Pop Off PSI

Here's a pic, I don't know if you can get a read on them tho. It runs the same in or out of the water. I've check the fuel pick up and they are both fine. I changed the selector during operation but no change. Compression was at 180. It runs fine from 0 to 1/2, then above that it sputters and hesitates. If I take of fast, put the throttle above 1/2 it will sputter as well, if I start slow and don't go past 1/2 it's "fine". Sometimes it will clear out and run better but I can still hear a little miss and hesitation.

[Dfleming]

Re: Pop Off PSI

I didn't look in the thoat to look at the butterfly but the lever is moving all the way through the range and hitting the stop.

[torquenut]

Re: Pop Off PSI

Can you take a close up of the plugs looks like the one on the right may be lean, but want better closer look at both

[Dfleming]

Re: Pop Off PSI

here's another pic, it's about the best I can do. If one side is rich or lean how can that be changed or adjusted?

[torquenut]

Re: Pop Off PSI

from this angle they look good. The high side spead screw will richen it on the high side, the lower on the low end. You screw in to make it leener, less gas/oil more air.
This is why a leak in the front seal you will loose gas/oil wich = lubrication.

[Dfleming]

Re: Pop Off PSI

so any ideas why I can't get full throttle out of my ski? I'm trying to same me some $$$ and not go to the shop.

[torquenut]

Re: Pop Off PSI

Well you need to break it down either a mechanical problem, low PSI etc starbation of fuel or electrical CDI.
Is there any other friend that may have a ski like yours to borrow parts?

[Dfleming]

Re: Pop Off PSI

Is there a way to test to see if I'm getting the correct amount of "fire" to the plugs? I'm going to run a fuel line from the tank straight to the carb and see if that help anything. I get the problem both in and out of water. The Compression is at 175, and the PO is at 38, the butterfly is opening all the way. Maybe just something in the carb I didn't get right when I rebuit it?

[torquenut]

Re: Pop Off PSI

Dude stop, your problem is mechanical, you are running on one cylinder or better to state your engine load is being carried by one cylinber.
You need to remove the head and take a look at the piston with the low compression. You may get by with new rings and hone.

[Dfleming]

Re: Pop Off PSI

I'll check them again but the compression on both cyl. was around 180 and holding, neither on blead down?

[Dfleming]

Re: Pop Off PSI

The compression in both cyl is 178 and it holds with out bleeding down. my manual doesn't say what the "factory" compression should be.