Sport Jet 120XR won't start

[dugjam]

I have a 1996 Sea Rayder f-16 with the 120xr engine. In the four times out I've had problems. First time I used two batteries before it fired up and ran fairly good 40mph. The second it wouldn't start at all. The third after changing plugs started for 20 sec then stopped. When trying again it sounded like it exploded (backfire?). When returning home it would turn by hand but could hear a metal sound when moving back and forth fast.Now the starter will spin up and engage the flywheel but just spin. Any ideas?<br />P.S The starter is spining not the flywheel. Also can you start the engine out of water and for how long?<br /><br />6-19-02 The starter bendix clutch assmb is spining.I'll try to repair it first. How can I check reed valves? What is sneezing? Is it backfiring? Can it be very loud like the exploding noise I heard? What damage can it cause?<br />I am grateful for any help.

 

[clanton]

Re: Sport Jet 120XR won't start

Check flywheel key, and compression.

 

[dugjam]

Re: Sport Jet 120XR won't start

Thanks for the reply clanton. The flywheel is OK,the pinion on my starter failed (more than likely from cranking so much)I have one ordered. When it arrives I'll test the compression. Can I start this motor out of water and for how long? I read in the forum about reed valves and sneezing. What is sneezing and do I pull the carbs to check the valves? Is it normal to hear a slight noise when moving the flywheel CW to CCW? Sounds like freeplay in gears. Thanks for any help. Doug

 

[clanton]

Re: Sport Jet 120XR won't start

It is sneezing, because its lean or cold. The backfire probley caused by being flooded. The largest flame I seen out of a Force 120 was 6 feet and set the pallet on fire that I was standing on. Starter working, compression OK, check spark, check fuel pump diaphram, clean carbs. Engine or jet pump should have flushing connection somewhere.

 

[aeronutt29]

Re: Sport Jet 120XR won't start

It's OK to start the motor out of the water and run it indefinately. Just make sure you have a hose hooked up supplying fresh water first! Even 5 seconds without water can cause serious damage to the water pump. If you've already done this, replace the water pump before you do anything else!<br /><br />Without knowing if the compression is good, the rest of our advise is probably premature. If your compression tests turn out OK, come back and post some more details of what you have tried. We'll help you out as much as needed!

 

[dugjam]

Re: Sport Jet 120XR won't start

clanton, thanks again. I'm still waiting for the pinion. Wow 6' flame, that sounds more like a flame thrower than a engine. I'm going to buy a flushing kit so I can run it out of the water. I'll post more when I get to that point.<br /><br />What a great web site!!!