HELP I'm starting to HATE this boat

[91RedPGT]

I have a 97 Challenger 1800, and as the title says I'm really starting to get frustrated this boat. It seems like every time I take it out something goes wrong and I am forced to limp back to the harbor on a single engine.

The latest issue is the port engine. It always starts on the first go around after launch, and then after about 5 to 10 min of running perfectly fine I can shut the engine off and it won't fire back up . Until a couple hours later. Then it will start just fine and run until someone accidently bumps into that stupid ass key and it shuts off, and it won't start again (then back to the harbor very angry and wishing that the boat would just sink).

Things I have done or tried this year.
- Carb rebuild (with good pop off)
- Resistance tested stator and trigger (with good results)
- Cut back coil wires
- Swapped coils
- Pulled red wire off rectifier (still no go)
- of course plenty of new spark plugs
- Oh and Compression is within spec (140ish on both cylinders)

If anyone could please shove me in a direction I would really appreciate it. I have put so much work into this boat the last couple of years (starboard top end rebuild, replacement of both jet pumps and solas props, reupholstered interior, wake tower and much more. I would rather not sell it at major loss because of something like this.

Thanks

Nick

 

[USAF_Pride]

Define "won't start"?
Does it just crank and not try to fire?
Does it attempt to fire, but just doesn't quite get there?
Are you using the choke?
Have you pulled the plugs during this and are they dry or wet?

You posted in the PWC section, maybe [MENTION=31048]LouDoo[/MENTION] or [MENTION=43374]Coastiejoe[/MENTION] can move this to the boat section where you may get some more help.

 

[Coastiejoe]

I can move the post.

Are you using the blower for the re-start? With the boats this is crucial as it needs fresh air to start. If not, the air within the hull simply does not have enough oxygen to allow quality combustion.

 

[91RedPGT]

Define "won't start"?
Does it just crank and not try to fire?
Does it attempt to fire, but just doesn't quite get there?
Are you using the choke?
Have you pulled the plugs during this and are they dry or wet?

You posted in the PWC section, maybe [MENTION=31048]LouDoo[/MENTION] or [MENTION=43374]Coastiejoe[/MENTION] can move this to the boat section where you may get some more help.

It will crank just wont fire. Every once in a while it will try to fire but just doesn't quite get there. And that is with or without the choke. And yes plugs are a little wet but nothing too crazy. And pulling and cleaning them off doesn't seem to help either. Then if you go back in a couple hours sometimes it will start right up with no problem and run fine.

 

[91RedPGT]

I can move the post.

Are you using the blower for the re-start? With the boats this is crucial as it needs fresh air to start. If not, the air within the hull simply does not have enough oxygen to allow quality combustion.

Yeah and usually the rear hatch will be open to so plenty of fresh air.

 

[FinnExplorer]

What happens if the dess post or key is bad? Does it crank but just won't fire? Could be the reason but don't know since mine only has the simple kill switch...

Also opening the hatch might not help enough since the vapors can still float around in the lower parts of the engine bay maybe?

 

[Waterluvr]

Nick your issue has all the classic symptoms of a carb that fails pressure testing, more typical of the common complaint on attempting a hot restart with no joy.

Diagnosis:
1. Verify ignition, you have it or you don't. Piece of cake so long as you have a proper CDI rated tester to do it with when that occurs a Stevens marine S-48H four wire spark / ignition tester will do the job in a matter of seconds and you can use it on anything up to one side of a V-8 motor. It's a must have tool for anyone trying to work on a CDI ignition equipped motor and you'll wonder how you ever lived without it the first time you use it.

If you have it move on to the carbs, if it's suddenly gone having done all the mandated resistance tests for components like a trigger coil or ignition generator coil are nice to already have on paper and do them again with everything heated up. Common enough to find things in spec while cold and out of range on resistance tests when hot, the before and after numbers are telling when compared to the factory testing pass/fail numbers in testing procedure.

2. Carbs, they pass a quick basic pop-off test and people assume that's good enough to rule them out without any further pressure testing. A complete pressure test needs to be done when the carb is partially assembled, I soak the seat base and needle with WD40 and introduce a small amount of pressure to see if anything bubbles around the o-ring on the seat or needle valve and I increase pressure all the way to the point of pop off from there. A bad o-ring on the seat is just as problematic as a worn or bad needle tip can be.

Leak testing when fully assembled should also be done, introduce 10-12 psi max (better to be slightly over ten psi than short of it) and eyeball the gauge to see if anything is dropping off pressure, if it doesn't hold for several minutes your valve seat is leaking from just enough contact from the diaphragm pusher to the lever arm and that's a really common problem that is missed in properly adjusting the arm.

 

[ialonso]

As carbs leak...

Sometime the carbs leak fuel still after you have stopped if things are not perfect. The engine may be flooded and you don't realize it.

It's hard to tell if you are flooded or starved, as the symptoms are similar (crancks , but won't fire)

If there is a chance you are flooded, try to start engine on Wide Open Throttle. If as you crack the engine catches a bit more, but sticks around 700-1000 rpm coughing some before starting, you were very likely flooded.

Most all my no-start issues with the boat have been carb related. Either too much fuel, or not enough.

Good Luck

 

[howie099]

A leaking needle and seat causes the hard starts. Just like everyone said you will get the proper popoff but a leaking needle and seat = hard starting. These are not included in the rebuild kits. Unless you know when you they were replaced go out and get 4 mikuni ones for your boat. Looking at like $60. Everytime I buy a used water craft. I don't care what the make is I re-do the fuel system and check over the oil system since these are always neglected. It saves you so much time in the long run since most people don't be proactive unless you get stuck on the water. Also since you have a rave valve engine make sure you adjust them and if your are still oil injected used the good seadoo approved full syn oil. You will be shocked what people do to save a buck..

 

[Sportster-2001-951C-Stock]

Starboard engine runs and starts hot and cold just fine. Port engine starts cold but won't start following a heat soak shutdown of any length (10 minute heat soak test is a standard and valid test) despite if I apply choke.

This sounds like your carburetor is leaking fuel into the intakes, when you rebuilt the carbs did you replace the metering needle and seat? If the needle tip is worn these can leak and stick, and become inconsistent.

It's my experience a proper carburetor rebuild should include a new replacement needle/seat set if they are more than a couple of seasons old. Many racers recalibrate their carbs and replace these between races.

If you are confident of the needle and seat/pop-off on the port carburetor then you may be able to swap them between engines to isolate the problem. Also if the fuel tank atmospheric vent check valves are sticking, then carb flooding problems can happen.

One test I apply to confirm if a carb is leaking fuel into the intakes and/or the idle mixture is too rich is to leave the throttle open a good amount (such as 50% or more) during shutdown and restart to see if the extra air helps the restart. This is the near polar opposite of applying choke.