Surfriding WOT ski is acting very weird. has no power then goes full speed then looses power

[peterlocal22]

Ski is acting crazy. When I go wide open throttle the power comes and goes while the throttle is held open. Its just nuts. Sometimes the ski wouldnt even turn over it was just totally dead as if someone took the cables off the battery. Then alittle later it would start but would have the initial same problem.
Anyone have any idea? Im going through my electrical connections right now but have no idea?

 

[Pablo]

Dirty internal carb filters. The engine is fine at low to mid fuel flow rates but at wot it starts to starve and cuts itself back until the flow catches back up.

 

[peterlocal22]

i will check it but the carb are brand spaken new second ride. Also power is not normal from low end, middle to full and due to the starting issue im thinking its electrical?

 

[Pablo]

If carbs are truely new and filters, fuel and gas tank are clean then rule out the internal filters. If it reliably starts and idles then I would check my ground cables for a secure connection and the spark plug terminals/boots for a leaking spark signal.

 

[peterlocal22]

what about the starting issues. One minute it will turn over the next nothing its just totally dead, then it will turn over, then nothing. is this thing possesed or what

 

[badvinny]

That sounds like ground cables to me.

 

[txsuperjetfreak96]

That sounds like ground cables to me.

x2

 

[Pablo]

Agreed

 

[peterlocal22]

I will check the grounds and report back thanks

 

[peterlocal22]

Yes it was a loose ground wire in the ebox.

I will bring the machine to the water today for testing and report back. Still not sure about the power issue but maybe that was it?

 

[mthomps]

Ski is acting crazy. When I go wide open throttle the power comes and goes while the throttle is held open. Its just nuts. Sometimes the ski wouldnt even turn over it was just totally dead as if someone took the cables off the battery. Then alittle later it would start but would have the initial same problem.
Anyone have any idea? Im going through my electrical connections right now but have no idea?

When it's crazy and random do a leak down test

 

[peterlocal22]

I ran the ski for about an hour today, no starting issues. The ski is still under power so I need to figure that out. Im changing the curve on my Epic to see if this is the issue, I was running a very safe curve because the motor is new. Let me know your thoughts I appreciate any input.

 

[mthomps]

You need to leak down test a new motor

 

[peterlocal22]

How do I leak down test the motor?

 

[hink320]

How do I leak down test the motor?

Get some block off plates like this.

http://www.fastelements.com/p-1233-h20-designs-block-off-kit.aspx

 

[CARBONX2]

Is the jetting right in the new carbs?

 

[peterlocal22]

I will order the block off plates today and check the jetting.

 

[Pablo]

Those fast elements plates are super nice. As a side note you can do the same thing with rubber compression stoppers/plugs. I've done a leak down test with these before. I borrowed them from waternut, but I believe he got them local at like Harbor Freight or a supply warehouse...maybe even Lowes or HD. I'm sure he payed bottom dollar as he's frugal.

I found some on eBay for like $5-8 each. Rubber winter expansion plug.








1. Leave ur ex manifold on and put one down in there and tighten it
2. Leave ur intake on and plug where the carb mounts
3. Use a bike pump or better a shock pump (with a pressure gauge) and attach some tubing and pump air into the pulse line on the intake side. Put 10-12 psi into the cases and let sit for a while...couple hours if u have the time. U'd like to see little to no drop on the pressure (less than 1-2 psi).
4. No or little drop = passed test
Large drop = leak. Then pump air back into cases and spray every gasket mating surface with soapy water and look for bubbles. When I see bubbles u found the culprit.

 

[JT_Freeride]

Here's how I did it. Same as He said but I just cut a steel plate and put it in between the manifold and head pipe

 

[badvinny]

Doubt it's the CDI, when they quit they either break up or fail. Put new sparkplugs in just in case, one could be fouling.