FX-1 New engine won't idle

[chadetroit]

I am trying to fire up my 62t 760 with epic and can not get it ti run. Starts everytime for about 1 or 2 seconds then dies. It is ported with dual mikuni 46s. Jets are 120 low 135 high. Set to 1.5 turns out. Sitting here starring at it does not seem to be making it better. I've played with the low jet maybe 1/4 turn each way with no luck.

 

[Waternut]

No amount of throttle will keep it running? Fuel tank vent pointed towards the tank? Fuel supply going into the bottom of the carb and the return on top? Pulse lines hooked up properly? Did you verify the timing? My guess is the fuel lines are installed wrong so check that first.

 

[chadetroit]

Fuel tank vent?

Carbs are in through the bottom, return lines out the top. I'm afraid to give it to much gas cause it seems like it wants to rev up, not sure if is me not use to the ported larger motor or not. I just plugged the pulse lines in, any thing else I should do?

Didn't check timing just set the stator to the case line and tightened

 

[chadetroit]

Other notes I have the cap off the fuel tank because I need to buy a "t" to feed both return lines into so for now I just have them running into the internal fuel fill neck. Not sure if it needs to be closed to create a vacuum to draw fuel.

Second thought is I have a smaller 650 factory chamber on there right now, long story I'm looking for a new chamber now. My worry is it's too small and choking the engine off.

 

[chadetroit]

Ok looks like I'm missing the fuel tank vent. I only have one nipple coming out of my tank is that for the vent? If so do I need to install another nipple for my return fuel? Sorry this is my first complete tear down and build, I've been learning a lot.

 

[DangerBoy]

Ok looks like I'm missing the fuel tank vent. I only have one nipple coming out of my tank is that for the vent? If so do I need to install another nipple for my return fuel? Sorry this is my first complete tear down and build, I've been learning a lot.

Did you change tanks ? should be 2 nipples on the battery side of the tank
one for the return from the carbs and one for a vent

however , I dont think your problem lies with , carb jettting, tank vent or the 650 chamber, those are all things that lead to a poor performing engine not one that wont run

when you crank the motor is fuel being returned to the tank via the return line from both carbs ? are the carb butterflys both in the same position ? if you put your hand over the carb for a sec while cranking is fuel sucked into the venturi, and my personal favorite did you remove any rags from the intake when you installed the carbs
if yes to all the above time to start looking at the ignition.

did you set up static timing on the epic ? did you verify the curve installed, did you make sure the computer plug on the epic is capped off so it cant touch anything
was the epic installed when the e-box got shorted out in your other thread ?

things to check
Db

 

[chadetroit]

Thanks for chiming in DB.

Yup I put an SJ tank in there. One nipple was lopped off and epoxied. I'll epoxy another one in there.

Return lines seem to trickle a little fuel but hard to tell if it pulling constant fuel. I'll try the hand trick tomorrow. Butterflies are in sync
yes all rags removed.

I didn't cap the epic hookup or the two lines that allow a switch to be installed. Another thing I'll do tomorrow.

I told ATP what I was running but have no idea what curve they put on there.

I did not do anything with the timing. Im lacking proper tools and knowledge in that category. Maybe I'll have to hit the ski clinic up.

 

[jetski9010]

You said your affraid to give it gas becasue it seems like its going to rev up? Are you talking about it sounds like it's going to run away? Are you sure you dont have any air leaks? How put the motor together? Is there two pulse lines coming off the case and if so are you using both? if not make sure the other one is capped off and air tight. Also make sure your carbs and bolted on properly and have all the gaskets and are sealing good. Dont turn your low speed screw in under 1 turn at least while your running it out of the water.

 

[QJS]

If its trying to rev up you're likely not getting enough fuel. To prove this start the engine then try to keep it running with the primer if you have one or by squirting small amounts of pre mix down the top of the carbs. If you can keep it running like this your problem is the fuel system.
Chris.

 

[chadetroit]

I do have 2 pulse lines both hooked up to their respective carb.

I will double check the Manni and carb bolts for tightness.

I'm going to open the ebox and tape off the epic plug and the two wires for switching curves.

I'll try the primer trick as soon as I'm sure the neighbors won't mind the wakeup call. My limited engine knowledge thinks I'm not getting enough fuel the way it is acting.

Note I am running a 62t setup with a jetmaniac lightened stock flywheel, not sure if that makes a difference. I read I should be able to just set the stator at the timing marks and be good to go.

I'll report back in a bit. Thanks everyone for the advice and help I'm truly grateful.

 

[chadetroit]

I've opened the ebox and taped off all connections I reconnected all the wires with dialelectric.

Tried the primer trick and it would not stay running when force feeding it fuel.

I even tried swapping the coil wires and had the same result as when they were on properly. Perhaps it is a timing thing.

I'm a bit stumped. If I had another cdi I would try that but I don't......

Wait might have found something. Gotta run to the hardware store for electrical fitting

 

[chadetroit]

Should I have a small red lead wire coming off both of my recoil large wires (battery and starter)?

 

[chadetroit]

That was the culprit. I had the epic hot wire hooked up to a red lead coming from the large cable that feeds the starter. So this cable was only hot while the starter button is pressed, making sense since it kept stalling right after the start. This electrical system I bought was cobbled together I think because wires were too short, rectifier was shorted out, and plenty of corrosion. Still no word from the seller who frequently sells on here so I'll give him a chance before I give feedback.

I'm assuming I can terminate that small red lead coming off the starter coil cable right?

Thanks everyone so much for the input, without checking off what did work I might not have narrowed it down.

Just going to do some dry 30 second starts periodically throughout the day to help the engine break in and then it's hit the water next weekend for some water breakin time and tuning....... Yet another new adventure I'm sure.

 

[QJS]

Never seen this before, glad you've found the problem, let us know how your ride goes at the weekend.
Chris.