I wrote yesterday 1996 GTX problem

[seamore]

Yesterday I described the problem as at WOT cycles between 6000 and 4500 RPM.
Checked voltage, engine off, battery at 12.5 V, at 3000 RPM (maybe more, couldn't see tach) was 12.8 V, changed rectifier, now at 13.4 V.

Still have problems, probably had them prior to rectifier change but didn't do enough test runs.

1) acceleration from idle to WOT RPM goes to 6900/7000, gets to plane then falls back to number (2), holding at WOT.

2) At WOT cycles between 6100RPM and 5800RPM 3 or 4 time then drops to 2000RPM then back too 6100RPM, repeats a few times then dies. Won't start immediately but will after waiting about 1 minute.

3) Slow increase in throttle from idle on up, runs rough till about 4000 RPM then jumps to about 5100 RPM no increase in throttle.

4) Slow decrease in throttle cuts out at about 4800 RPM and drops to about 3800 RPM no change in throttle, runs rough.

5) Changed plugs and retried no difference, pulled plugs both looked the same, a little oily.

Just but Saturday, my first wave runner, guy I got it from just spent $917 dollars at dealer to rebuild carbs and get it running right. Dealer says that when he picked it up that it had electrical problems. Sea Doo looks new, was told low hours, very clean, did visual on wires, no corrosion, no visible problems anywhere.

Thanks!

[seamore]

Re: I wrote yesterday 1996 GTX problem

Forgot to say, runs smooth from 5000 RPM to 6000 RPM, about 44 MPH at 6000 RPM.

[Bill O'Neal2]

Re: I wrote yesterday 1996 GTX problem

You just described a motor that has siezed due to a lack of fuel getting into the motor. There are other possibilities to cause this type of problem, but the fuel starvation is the most likely senerio. This is how they act when the internal fuel filters inside the carbs are clooged up.

Next thing is tell me what the two clyinders are pumping on a compression tester.

[seamore]

Re: I wrote yesterday 1996 GTX problem

Thanks Bill, my first guess would also be fuel starvation, just like when a fuel pump would go on my 56 ford, hit the accelerator and it slows down.

[frankey01]

Re: I wrote yesterday 1996 GTX problem

exactly do NOT ride that ski again until you have run compresion numbers. Hate to say it but if you are low you will be spending more money on it than what you just paid for it.

[seamore]

Re: I wrote yesterday 1996 GTX problem

I'll take your advice, will try to get a compression checker tomorrow

[seamore]

Re: I wrote yesterday 1996 GTX problem

OK guys, couldn't stand it, went out and got a compression checker. 160psi in front, 165 in rear, next?

[frankey01]

Re: I wrote yesterday 1996 GTX problem

those are good compression numbers but compression is not a tale tale of whats going on last time the carbs were rebuilt? what does it look like under the head ? have you checked the pistons?

[seamore]

Re: I wrote yesterday 1996 GTX problem

I haven't had the heads off.
Dealer rebuilt carbs last week and welded 4 soft spots on exhaust that were not leaking. Supposedly everything to do with a gas problem was fixed. Was told gas was about to "gel" or had "gelled". Guy I bought it from paid $917 for service. Notes on the bill says that there is an intermittant electrical problem.

[Bill O'Neal2]

Re: I wrote yesterday 1996 GTX problem

Has anyone done the simplest thing? Like clipping back the sparkplug wires for a good connection at the sparkplug boots.

[seamore]

Re: I wrote yesterday 1996 GTX problem

I guess I'll try that, was also thinking of cleaning the RAVE valves. Someone told me to try "Sea Foam" gas treatment, little nervous about putting anything in the fuel on a 2-cycle motor?

[Bill O'Neal2]

Re: I wrote yesterday 1996 GTX problem

Sea Foam is safe to use.

[surveyguy]

Re: I wrote yesterday 1996 GTX problem

you'll probably want to do a block leak down test.

[Bill O'Neal2]

Re: I wrote yesterday 1996 GTX problem

Cleaning the rave valves every 50 hours is a "normal" maintence item. But, even if they were stuck shut, it would not make your motor do the things you described.

Is there any signs of water on the sparkplug or rave valves ? This part about needing to weld the pipe makes me wonder if water is getting sucked into the clyinders through the exhaust manifold because of a leak in the waterjackets of the tuned pipe.????
That would make a motor rev up, then down, and run like dog poo poo.

[seamore]

Re: I wrote yesterday 1996 GTX problem

Hi Bill,

Just got thru cleaning the rave valves, looked like they have never been cleaned, would suspect thatr they were stuck one way or the other.
Motor looks really clean, no sign of leaks of any kind. I'll probably give it a test run after work tomorrow, will reply on this thread how it's doing.
Didn't clip the spark plug wiresyet, boot is on tight and I don't want to take it apart till I have some way of fixing it. I'm going to do one fix at a time between test runs so I'll know what the heck the problem is.
The guy I bought it from says he's sure the shop didn't change the gas, there was about 10 gallons in the tank and no charge on the repair bill.
I see what looks like a replacable in line fuel filter on one of the flexible lines underneath, suspect it's a through away so haven't touched it yet, not sure if it's on an oil or gas line.
I'm a bean counter so all this mechanic stuff is new to me but I want to know how to take care of this thing once it's working right.
Thanks for your help
Chuck