1996 Seadoo Challenger Problems (Video)

[makaveli07]

Hey everyone! I have always had great luck with getting help and learning new things on this forum as it is my first year with Seadoo's and watercraft's for that matter. Here is to hoping I can get some more help and direction as to how I should approach the following problems:

I took out my recently purchased 1996 Seadoo Challenger with the single 787 engine for the first time to test it out knowing that there will be some problems for me to address through the winter.

I have linked a video in the bottom of this post to clarify the problems further, the video includes short clips of the issues I ran into.

Problem 1: For the first 5-10 minutes running the boat it felt a little choppy if I pushed the boat with full throttle I would get hesitation in the RPMs where they would reach around 6200 and drop down to 5800 for 1 - 2 seconds then go back up to 6200 and the boat would not plane out. After the 5-10 minutes this problem stopped occurring.

Problem 2: The water regulator is leaking in the engine compartment on idle it would only leak a little but once i push the throttle it would leak badly.

Problem 3: Boat is very slow to plane and slow top speed. It taking maybe around 30 seconds to reach plane with 2 light adults on the boat and would max out at about 6800-6900 RPMs and 37 MPH

Problem 4: Boat is smoking a lot through the tailpipe especially on low speeds (could be normal) but seems to be smoking much more than my 1997 SPX with the same engine.


Link to show the problems:

Any help is much appreciated,

Thanks in advance for all the help!

 

[POPPS]

That water reg is there for bottom end, and then shuts off. Since yours is leaking, you are not getting total bottom end performance, and it will hinder top end.

 

[makaveli07]

That water reg is there for bottom end, and then shuts off. Since yours is leaking, you are not getting total bottom end performance, and it will hinder top end.

Can that water regulator leak also cause the rpm fluctuation and the boat not to plane out in the first 5-10 minutes of running? or is that possibly due to cavitation? or possibly dirty carbs?

 

[gazzaskirepair]

I would also take out the Rave valves and give them a deep clean they will give you slow acceleration and also hinder top end RPM
But get the water leak fixed as that effect Ets the tuned exhaust pipe

 

[makaveli07]

I would also take out the Rave valves and give them a deep clean they will give you slow acceleration and also hinder top end RPM
But get the water leak fixed as that effect Ets the tuned exhaust pipe

Alright so I’ll start off with water regulator leak first then clean the rave valves. Is it possible what i was experiencing in the first 5-10 minutes was cavitation ? Should i rebuild the Jet pump?

 

[gazzaskirepair]

Was this boat standing for awhile before you took it to the water ?
Previous owner used it when last ?
Could have bad fuel

Just do things slow in the boat which will prevent you building in new problems that could effect effect present problems
Seems to be running close to max RPM

Get under boat and look at the impeller to confirm no damage and can check drive shaft too

Smoking could be oil pump adjustment or oil brand being used
After riding boat hard you’ll need to shut engine off remove spark plugs and check the color should be a brown to tan and no oily ness

 

[makaveli07]

Was this boat standing for awhile before you took it to the water ?
Previous owner used it when last ?
Could have bad fuel

Just do things slow in the boat which will prevent you building in new problems that could effect effect present problems
Seems to be running close to max RPM

Get under boat and look at the impeller to confirm no damage and can check drive shaft too

Smoking could be oil pump adjustment or oil brand being used
After riding boat hard you’ll need to shut engine off remove spark plugs and check the color should be a brown to tan and no oily ness

Exactly what I plan to do. I will go over everything and make sure its all good before i take it out again. Previous owner says he ran it all summer (so should have fresh gas) as he states it was 94 gas from chevron.

Boat sat for about 2.5 weeks before I got it in the water

The previous owner used TC-W3 meets or exceeds expectations for API TC. I will be syphoning the oil out and switching to XPS as that is what i use in my 97 SPX.

Pulled the spark plugs they are not wet/oily at all but black in colour not brown.

I will be going to the storage unit to check the impeller and the driveshaft a little later today.

Thanks for all the tips and guidance!

 

[brownie545]

That has to be the cleanest 96 challenger in existence!

 

[makaveli07]

That has to be the cleanest 96 challenger in existence!

haha thanks, I only buy them if they have been used only in freshwater. If you think this challenger looks clean you should see my 1997 SPX, went through that thing with a fine comb and made sure everything is done properly. Planning to do the same with this!

 

[POPPS]

Certainly, your first move is to reseal the water regulater and remove it from your diagnosis equation, if it is still on, as you increase rpm, the motor will not rpm out, and you will be sluggish out of the hole. The intermittent lean bog I heard, normally is fuel related, start simple, and start from the fuel pickup, then the selector switch( difficult to get at) , easier to by- pass the selector switch and go directly to the carb. That will rule out a bunch of potentials. Also make sure you're fuel filters are clean, ( does it have a water fuel separater, can't recall) .

 

[Marksfun1]

That has to be the cleanest 96 challenger in existence!

Did you see how clean the engine compartment is? Crazy clean ....

 

[POPPS]

Trust me, I just had 180 challenger jet boat with twin 4 tecs, engine compartment spotless, owner bought it without seeing it being run. Well, both motors were full of water, the boat had been submerged, he paid $11 000 for it, and now it is junk! So, a clean engine compartment, doesn't always mean a great running motor.

 

[brownie545]

Good because mine is disgusting lol

 

[POPPS]

LoL!

 

[makaveli07]

Certainly, your first move is to reseal the water regulater and remove it from your diagnosis equation, if it is still on, as you increase rpm, the motor will not rpm out, and you will be sluggish out of the hole. The intermittent lean bog I heard, normally is fuel related, start simple, and start from the fuel pickup, then the selector switch( difficult to get at) , easier to by- pass the selector switch and go directly to the carb. That will rule out a bunch of potentials. Also make sure you're fuel filters are clean, ( does it have a water fuel separater, can't recall) .

Thank you for the advice. Tonight I will be ordering a new fuel switch, a new water regulator, new water separator filter and oil filter. and in the meantime I will take apart the carbs and the rave valves and clean them. and readjust everything to factory specs including oil pump and throttle cable.

 

[makaveli07]

Good because mine is disgusting lol

Take some super clean to it and warm water, it does wonders for your engine compartment. avoid pressure washing for obvious reasons, just a regular garden hose and super clean.

 

[makaveli07]

Trust me, I just had 180 challenger jet boat with twin 4 tecs, engine compartment spotless, owner bought it without seeing it being run. Well, both motors were full of water, the boat had been submerged, he paid $11 000 for it, and now it is junk! So, a clean engine compartment, doesn't always mean a great running motor.

Yeah I generally look at how the owner takes care of it which is usually an indication of how it was treated. for example when i bought this boat the owner had a bunch of marine antifreeze left over and fogging oil which indicates he winterized the boat properly, and i did my due diligence by pulling the spark plugs out and making sure its not flooded etc... but i expected for some things to need work as its a 96 after all, and either way i would have done most of the maintenance I'm doing now anyways because I'm OCD like that LOL

 

[Sandman251]

Great looking boat! Regarding problem 1 in your video; when it's in this funk condition, pull the choke. Does the boat puke out and die or does it get a shot up to full RPM? If the motor surges you are running lean and should stop running it immediately till you sort out the fuel delivery problem. Regarding problem 3; I've owned 2 787 Challengers. 37 mph is reasonable speed for 6800 RPMs. If you can squeeze out another two or three hundred RPMs you will be in the low 40 range which is about what you should expect for this boat with fuel and two adults. Of course that doesn't explain why it takes so long to get to Max RPMs, but in your problem 3 video the boat sounds good. Just wondering if your Speedo numbers are GPS or Sea-Doo cheat ometer.

 

[makaveli07]

Great looking boat! Regarding problem 1 in your video; when it's in this funk condition, pull the choke. Does the boat puke out and die or does it get a shot up to full RPM? If the motor surges you are running lean and should stop running it immediately till you sort out the fuel delivery problem. Regarding problem 3; I've owned 2 787 Challengers. 37 mph is reasonable speed for 6800 RPMs. If you can squeeze out another two or three hundred RPMs you will be in the low 40 range which is about what you should expect for this boat with fuel and two adults. Of course that doesn't explain why it takes so long to get to Max RPMs, but in your problem 3 video the boat sounds good. Just wondering if your Speedo numbers are GPS or Sea-Doo cheat ometer.

Ahh, thank you for the clarification and advice, I thought these boats can see mid/ high 40s. In any case, I have so far inspected all the fuel lines all seem good, I have changed the fuel switch, replaced the water regulator (thanks to Nick at Westside powersports). and cleaned the raves, and adjusted to factory specs. unfortunately I have not been able to test anything as its already freezing here, so I will need to wait till at least May when the weather becomes acceptable again. I still need to take out the carbs and clean them and change the water separator and oil filters. unfortunately I was looking at the Seadoo gauges (might have been a mistake as I now know they are not very accurate).

 

[POPPS]

Can that water regulator leak also cause the rpm fluctuation and the boat not to plane out in the first 5-10 minutes of running? or is that possibly due to cavitation? or possibly dirty carbs?

.

If the rpms fluctuate, then in most cases it is fuel delivery,,,( usually carbs, micro filter) , with an outside chance of water in the tank, just have a look in your fuel/ water separater to rule that out.

 

[POPPS]

For true mph, gps is the truth.

 

[makaveli07]

.

If the rpms fluctuate, then in most cases it is fuel delivery,,,( usually carbs, micro filter) , with an outside chance of water in the tank, just have a look in your fuel/ water separater to rule that out.

Fuel is new and has fuel stabilizer in it, I will check and replace water separator filter anyway and take apart the carbs and clean them well! hopefully that should fix any issues there.

 

[makaveli07]

For true mph, gps is the truth.

Yeah, I need to check through GPS and hopefully, it has gone up after replacing and readjusting the water regulator to factory specs.

 

[POPPS]

You don't have to replace the fuel filter, just remove it and use carb cleaner with some light compressed air. Be careful replacing the fuel cup, that you do not cross thread it, since they are just plastic.,,it should thread on smoothly.

The small micro filters in the carbs, are usually the culprit for hesitation, leaness, and also for lean seizures, (engine failures) .

 

[makaveli07]

You don't have to replace the fuel filter, just remove it and use carb cleaner with some light compressed air. Be careful replacing the fuel cup, that you do not cross thread it, since they are just plastic.,,it should thread on smoothly.

The small micro filters in the carbs, are usually the culprit for hesitation, leaness, and also for lean seizures, (engine failures) .

Yeah, I remember those were quite dirty in my 97 SPX as well, I thought it was due to the grey temp fuel lines that I changed out. I guess they get dirty overtime regardless. I wish I can take it into the water and test it sooner than May haha but since I got lots of time before the weather improves I'm taking things slow and going at it one thing at a time.