engine running problems

Hi

Yesterday i installed a new red stator and the adaptorkit, and i got spark on all 3 plugs.. but i can't get the engine running.. the starter runs fine, and the engine sounds healthy, but it won't start.. did you guys have any idea what it could be? is there some kind of choke on these engines?
I wonder if my stator direction are wrong ?

any help og "starting-tricks" out there ?

Thanx Kenneth

Re: engine running problems

engine description and why the stator change would shed some light on the problems you're having.

Re: engine running problems

it's a Sport jet 90 engine, and i changed the stator and flywheel because the old flywheel suddently losen off and destroyed stator and magnets inside... now i got spark on the plugs, but can't get the engine running...
I wonder if it's still an ignition problem, or maybe the water pressure was to high on the waterhose i used to water flush the engine, when i tried to start it on the trailer :-(

The sparkplugs smells of gasoline, is there any way i can see if there's getting water into the cylinders?

Re: engine running problems

Re-check the timing.

Art

Re: engine running problems

if the flywheel came off then you're gonna have to start from scratch and re-time everything.
timing is everything on any engine. you need a factory manual or either time to take it to a shop to have it done!
the reason you smell gas in the cylinders is because the plugs are firing before the gas is delivered into the cylinder and the exhaust valves are pushing it out before it can be ignited.

you're gonna have to start with finding btdc with the pistons in relation to the position of the flywheel then you need a timing light to set the base timing to get your spark back in sync.

Re: engine running problems

The flywheel should be keyed to only fit one way. If you want to check it manually, remove all plugs and gently insert a screwdriver or long rod into the top cylinder. You should be able to feel the top of the piston with the screwdriver...don't apply pressure. SLOWLY turn the flywheel clockwise by hand (should be easy with all plugs out) and allow the screwdriver to move freely. You should be able to tell when it is Top Dead Center (TDC) by when the screwdriver stops moving out (towards the spark plug hole) and starts to move back down. At this point look at your timing mark. It should be at 0 (zero).

There should also be an aligment indicator on the Stator for orientation similar to this one. If you can't read the text in the picture, it says something like "position this arrow pointing aft for 70-120 sport jet engines":


Water pressure should be minimal. Holding the hose straight out in front of you it should look something like this. If you have more pressure water will enter the cylinders and hydrolock (won't crank):

Re: engine running problems

thanks that was a great post!!

now i understand the position thing, i'll try that tomorrow

But what to do if i have filled the cylinders with water, the first time i tried it maybe there was a little to much pressure on the waterhose.. if thats the reason it won't run, what do i have to do then, and how can i find out about "water damage"?

and last question: what is a hydrolock ?

again - thanks alot to all inputs!!

//Kenneth

Re: engine running problems

kokaninus said:

.....and last question: what is a hydrolock ?

again - thanks alot to all inputs!!

//Kenneth

Click to expand...

Hydrolocking is where you get a good amount of water into the cylinder. Since water is not compressible, mechanical damage usually ensues . This can include bent and/or broken connecting rods; cracked pistons, heads and cylinders. Not good!

Re: engine running problems

As a Yamaha certified watercraft tech I can not repeat this procedure often enough-when cranking any PWC out of the water 1. hook the water supply hose to the inlet on the watercraft, DO NOT TURN WATER ON YET 2.CRANK MOTOR ONCE MOTOR IS RUNNING TURN WATER SUPPLY ON.3. RUN AT LEAST 5 MINUTES AT IDLE TO THOROUGHLY FLUSH SYSTEM.4. TURN WATER SUPPLY OFF, REV ENGINE 3-5 TIMES TO CLEAR EXHAUST AND THEN KILL THE MOTOR. If you run water to a PWC without it running you will back fill the cylinders with water and cause hydro lock. I have replaced cylinders on PWC's that owner's tried to crank after water had been turned on first ( same customer twice) when the piston tried to compress the water it busted the cylinder right off the case not to mention bending the rod. So remember - ENGINE ON - WATER ON, WATER OFF - ENGINE OFF[ /U] in that order!!! You can safely run the engine without water 45 to 60 seconds giving you plenty of time to walk back to the faucet.

Re: engine running problems

If you start the sport jet without water on you will blow the ride plate off resulting in $$ repairs. The water flow is needed as unspent fuel vapors will collect from the exhaust and ignite at startup causing this to happen. The water flow carries the unspent vapors away.

Re: engine running problems

wow... confusing... Hmmm lets pretend that i have filled the cylinders with water, im not sure i have, but lets pretend... then what do i have to do to get rid of it ?

and how do i find out, if there is water the wrong places ? can i remove the first sparkplug and then locate it?

Thanks

Re: engine running problems

kokaninus said:

wow... confusing... Hmmm lets pretend that i have filled the cylinders with water, im not sure i have, but lets pretend... then what do i have to do to get rid of it ?

and how do i find out, if there is water the wrong places ? can i remove the first sparkplug and then locate it?

Thanks

Click to expand...

The way to get the water out of the cylinders is to remove all of the spark plugs and then crank the motor over. If there is water in the cylinders, it'll come shooting out.


posted by ajaxcycle,

....So remember - ENGINE ON - WATER ON, ENGINE OFF - WATER OFF in that order!!!

Click to expand...

You meant, WATER OFF - ENGINE OFF

Re: engine running problems

Yes...sorry for the confusion. The Sport Jet is different than most other jet powered craft. I can't speak to waverunners, but the ride plate blowing off comes from first hand experience...and many other Sport Jet owners have encountered the same issue.

The water pressure in the photo comes from first hand knowledge/practice from running in the shop.

Re: engine running problems

Calledinsick: i know you are a wise man in these engines, see you helped alot of people out of their boat troubles - respect!!
I'll try the methods you posted above.. hope to get her running soon.. the summer is here, and hate to see her standing on land

Dannyual: do you think it's enough to get the water out?? im not yet sure if theres water in the cylinders, but my poor side of the brain tells me there is ..

Re: engine running problems

Thanks, but I'm still learning these engines every day.

I agree with Dannyual...pull all 3 plugs and crank to see if water comes out...it may come out when you pull the plugs if there is enough in there. I would add that I would ground all 3 plugs away from the plug holes (plugs sparking near the holes *could* ignite the fuel vapors).

I made a simple grounding device from a household bare copper ground wire.

I took an old spark plug and wrapped the copper wire around the threaded end to make 4 loops. When you pull the plugs you can place the base of each in each loop (spark plug boot on) and the fourth hole can be grounded to a bolt on the engine.

Crude drawing (no laughing!):

Re: engine running problems

Hi Guys .. great to see some of my old friends helping out in here !! The advice is very sound and accurate that has been given . I would do it in this order ,
1 pull the plugs and turn the motor over to be sure there is no water in the cylinders.
2 Check for spark by using the home made ground system shown above , that is the same as I use .
3 Are you sure the flywheel key is still in ?? these things can come out of the groove when flywheel is installed .
4 if all looks good then go to the first post in this section Sport Jet Info and read it !!! and test the trigger according to the instructions , it looks really burnt on top .

Post the spark / no spark results and the trigger ohm results .. with the help you have in here you will be on the water in no time !!

NEVERMIND , did not realize who started this thread :facepalm:, read my response to your prior thread and it should help but do try to flush the water out of the cylinders to be sure !!!

Here is what I posted

Getting spark is the real battle on these engines , Yes there is a choke or an auto enricher , From what I can tell you have an eletric choke , the shaft on the back of the carbs , fuel line side , by the vent lines where they attach to the air box is your choke linkage and yes you must choke the motor to get it started cold . See if the ignition key pushes in while in the switch , if so that is how you activate the choke . You should be able to hear them click closed

Re: engine running problems

the boat runs perfect now - THANKS A LOT!!!... But i've only got one problem left, hope someone can push me in the correct direktion

http://forums.iboats.com/showthread.php?t=455989

Re: engine running problems

Choke wire is yellow/black tracer . a new switch with push to start should be about 25 bucks.

Re: engine running problems

You might look here...this looks to be the correct key switch but I'd double check!

here