96 challenger, Please help

[2qwk]

Hi Everyone, I am new here and have recently purchased a 1996 Challenger. I am having what I hope is a small problem. The boat runs 100% perfect until I get it just over 3/4 throttle then it cuts out. If I go just under that point it runs fine, if I hold it on the fail point of the throttle it will kind of surge, get fuel then lose it. A little past the point and and it cuts out, just under the point it runs perfect. When the throttle is at the furthest point before it quits it almost has enough power to plane but not enough unless the 1 passenger goes up front. Now when I was testing it I decided to lift up the choke a little at the cut off point and it cured the problem, it would go full throttle and have what I think was all the power (7000rpm). But even with the choke up a little after a little while it started doing the same thing. I am thinking dirty carbs. Already changed the fuel filter. Any help would be so appreciated...I really like this boat and it is in perfect condition...I have no manual and if you guys could tell me what hp and engine I have or any other stats on the boat or where to find them that would be great. I think I know what it has but I cant be sure. This is my first jetboat.

Randy

 

[glenwhitt]

ok

7200 is rev limit on the 96 boat. Do not run it anymore like you are. You are lean and it will purn a piston. At 3/4 throttle you are getting into the high speed circuit. check your carbs/rebuild. Could be the fuel pump on the mag carb not keeping up also. Had a simular problem on mine. Check all lines, filters (in the carb also) fuel selector, etc.... Do you have grey fuel lines on this? if so replace them with good marine fuel lines.

 

[pincusa]

For sure, do not continue to run the boat like that. You'll blow the engine and need a lot more work than a carb clean out.

Take the carbs out and rebuild them. Use carb cleaner spray to clean out all the little channels. And if you have compressed air, blow it all out to help get anything else out. There are a few threads here that have lots of pictures on how to rebuild the carbs. Here's one of them. SBT sells rebuild kits.

 

[2qwk]

Thanks for the info. I only ran it like that for a 15min test ride. I have already removed the carbs. A friend of mine who has taken apart and cleaned many carbs before is going to do the actual carb cleaning with me. Sounds like I should buy the gaskets for where the carbs go to the intake and a new fuel pump for the (mag) carb. The fuel lines are not grey they are black but I think I will buy a large piece of marine fuel line and replace everyone I can get my hands on. Thanks for the link, I will bring my laptop with me to his house tonight for reference when he cleans the carbs. I think with the carbs cleaned, the new pump, the lines and the new gaskets it should fix the problem. If there is any other small things that I can do myself why I am in there, Please let me know.

WOW, Thanks so much for the help and the super fast replies. Looks like a great forum here..............



Randy

 

[glenwhitt]

if you are not premix already make sure the oil injector pump cable did not come off the pump on the mag cover. If it did it will smoke the block with oil as it goes wide open. Be sure and time this also when putting the carbs back on. proper oiling is crucial for these.

 

[2qwk]

Ok. My friend and I took the carbs apart tonight. We found a good size piece of crap in one of the jets on the carb without the fuel pump. I hope this was the problem, I will test it tomorrow. I plan to just put the cables back on the way I took them off. I am not familiar with the oil injection setup. I am wondering if it would be best to switch to premix.

I would be truly greatful if someone could point me to a good place to by replacement parts for this engine online. A phone conversation with the parts guy at the local seadoo dealer did not go well today. I asked him if I could buy just the fuel pump for the mag carb and he told me that it is part of the carb and to buy it, it would be $400 if he can get it, he said it is a very hard to find part now ( doesn't sound right to me). The jet had a good size piece of white corrosion substance inside it and I am confident this was the problem, I will know for sure tomorrow, wish me luck, and thanks so much for the help...


Randy

 

[glenwhitt]

dealer pricing

ya the dealers go straight out the book. I just abought a new cdi for my boat oem in the box brand new, for $278.00. Dealer wants over $700.00. I replaced both my carbs this year with oem mikuni's and it cost less than the $400.00.

You can try
http://www.seadoowarehouse.com/
and
http://www.parkeryamaha.com/
and
http://www.ebay.com

 

[glenwhitt]

oh ya. CHECK THE FILTERS IN THE CARBS, if have not already. It was joke there with the yelling. Good luck and good wakes

 

[2qwk]

Test Results

Test results are in!!! I took the boat out and it ran perfect. 20mins into driving it, I was convinced it was fixed for sure. Then it happened, it started the same thing again. This time the fail point was much higher, just barely off full throttle. Then as I kept going the fail point came down some, almost to 3/4 throttle. Then I shut the boat down and let it drift for a good 10mins. Started the boat back up and it ran fine for 3mins then started again.

I am not 100% sure if my friend cleaned the filters on the carbs. I will ask him when I meet him after work tonight to clean the carbs again. This time I am going to try and download a diagram of the carbs from somewhere and make sure we get the filters. (any thoughts?)...........



Randy

 

[2qwk]

oh ya. CHECK THE FILTERS IN THE CARBS, if have not already. It was joke there with the yelling. Good luck and good wakes

There was much need for the yelling.

I got a diagram today and we did overlook the filters in the carbs. The one in the Mag carb was full. I can't even believe the engine ran with it like this. It must have been the problem. I will be 100% sure tomorrow. Thank You so much for saying that. If you didn't I would not have found them. It was a good thing that we had to do more work because I did find a couple of other small, minor things that needed attention and I was able to fix.

I will post how it goes tomorrow, Thanks again...........


Randy

 

[seadoosnipe]

Twin carbs?....

All the info in this thread is good but nowhere did I see a suggestion to read your plugs. You did find gunk in your carb but for me the question would be, "how did it get there"? The micro mesh filters are suppose to keep all trash from entering the carbs.

If you had trash in your carbs, I'd make sure that all the internal porting was clean by spraying some carb cleaner through the ports. You can use that little red hose that comes with the can to spray into the holes, you'll see it exit mostly into the throat of the carb.

Don't forget to check the lever and needle valve seat. With your problem discussed and with all the replies, it seems, just to get it running good should be the goal, so stay on track with what I'm reading here.

There isn't any posts about your syncronizing the carbs to each other. This is done with the idle stop screw all the way backed off the mag carb. Then, take that bar that connects the two carbs together. Pop it on the mag carb. Now, put the ball up to the pto carb. If it doesn't line up to that ball just perfect, adjust it till it does.

After you do that, turn the thumb screw on the idle stop screw in 2 turns.

If you can help it, leave your oil injection pump on. The cost of oil for premix is astronomical!.........You'll use three times the oil.

After you sync the carbs, you'll need to take a mirror and look down at the front of the engine, in front of the magneto. That little thing with the cable, that's the oil injection pump. The edge of the roller cam should be in the center of the dot of the up-raised portion of the pump. Almost setting at 11:30 on the clock.............

Your engine is the 787 cc with 110 horsepower. At the foot, it's about 32hp.

Lastly, your RAVE valves need to be cleaned. That is those little black covers you see with the red cap in the center. You'll see two allen head screws holding them on. Take off the PTO first and inspect it. Look at the slide valve for carbon build up. IF it's bad, you'll need to clean it and go aheand and pull the MAG. You have to seperate the mag bellows from the slide valve to get it all out. The exhaust manifold is in the way to just slide it out.............

This is a very good, informative thread. I'll look forward to reading your results. Look in the boat section and you'll see a sticky, "a look inside the 787"....this will show you what the RAVE valves look like before you take them out. I'd also take a peak at my thread "snipes Korner". There is tons of info there for beginners that will make you a pro fast!.....:cheers:

 

[glenwhitt]

snipe is right

do not just fix the problem. fix the problem and the reason you had the problem or you will be fixing it again

 

[2qwk]

First I would like to thank Glen again for helping me.

I drove the boat for 4 hours today. Not one single problem, The boat could not have ran better. It was definetly the crap in that filter that was the problem. I would like to add, last night when we cleaned the filter we also pulled the sending unit, the screen that goes on the bottom was in the bottom of the tank. We fished it out with wire and reinstalled. I don't know why the other inline filter did not catch it.

Snipe, as far as your post goes. I am going to show my friend and see what in there we are comfortable doing ourselves. He is a much better mechanic than me, but neither of us are seadoo mechanics. A lot of it does not look very complicated and I will try to do as much of the things you listed as possible.

I hope that someone who has the same symptoms can find this thread helpful, And thanks so much for helping me fix this boat, for under $20.00 at that..............................You guys are the greatest..............


Randy:hurray:

 

[glenwhitt]

Glad you are up and running.

 

[mrclean667]

filters on the carbs

Where are the filters that are on the carbs that you guys were talking about in this thread that 2qwk overlooked and finally cleaned. I would like to inspect them as well since I just purchased A 96 challenger.

Thanks all
mrclean667

 

[timmyboy76]

Where are the filters that are on the carbs that you guys were talking about in this thread that 2qwk overlooked and finally cleaned. I would like to inspect them as well since I just purchased A 96 challenger.

Thanks all
mrclean667

Follow the fuel line from either external pump or the inline filter, to the carb. The "internal" filter is on that side of it, plus, if dual carb, it has one on pto carb also.