Freestyle Jetmaniac ported 701 - 210PSI - too much for regular pump gas? (PROBLEM SOLVED)

[80jay]

I just recently had this problem with a friends ski. I ended up changing the coil,stator and putting in a msd enhancer. It was having the same symptoms and sound as your motor.

 

[Waldbjoern]

The idle isn't the best no.. But to give a hint to why I think it's a carb problem, is that the last two times I've taken the carps apart and cleaned them good, the boat ran like a 1000cc - but only for like 10 minutes. After that it just started getting worse and worse. Same both times :/

 

[Waldbjoern]

Well different CDI has bin tried with no luck, and also the coils has bin changed with no lock. But haven't touched the stator, only had the flywheel out to see if things were as expected - which they were.

 

[Byeai]

Sounds like stator issue

Sent from my SAMSUNG-SGH-I727 using Tapatalk 2

 

[stefan]

Have you tryded too run the boat with out the Hood ? too check exhaust leaks maybe try another carb setup ???

 

[Schmidty721]

Sounds like it is only hitting on one cylinder when that noise occurs.
Positive you don't have a fuel delivery issue to the carbs? Pickup tubes clean in your fuel tank?
Maybe been covered but fuel vent working correctly?

How about the water box. Don't have a broken baffle by chance do you?

 

[Waldbjoern]

Regarding the fuel line imm 100% that there is nothing plugging it. Also the valve in the tank works correctly.. But regarding the waterbox - that's not bin checked!! That's on the to do list tomorrow. Also I have a new set of carbs coming my way that imm going to try tomorrow that has bin said to work. So fingers crossed, and lets see what happens. If none of the above things work I think the next step will be the stator coils and 80g springs.

Progress report will follow.

 

[sjetrider]

just because carbs are rebuilt rejeted doesnt mean they are jetted or set right? Sounds like it is going lean at mid to top, might look into increasing top jet or reducing pop off via larger needle and seat.

Really hard to diagnose via the description though, it could be coil, CDI or timing as well.

 

[jetx]

I'm surprised no one has mentioned this but if your running dual
38's that jetting is not correct, that looks like the single 44 on 61x cases.

I would say youd want to be at 75 pilot, 137.5 main, 1.5 needle and seat and 115g spring if your running stock flame arrestor. It would be a wise idea to contact jetmaniac for his jetting specs on that motor.

Main Jet : 145
Pilot Jet : 120
High speed screw : about 1 n a half turns out from closed
Low speed screw : about 1 n a half turns out from closed
Needle & Seat : Stock
Spring 95 grams

Hmm, might wanna try with the shell V-power !

When going up slowly and not putting too much resistance on the engine/prop, then you can make it go faster! Its when the engine has to work hard that it gives up!

 

[jaxrider]

maybe unplug stop switch

 

[icecoled007]

Did you blow in the one way valve on the tank? I have seen a faulty valve cause similar issues before

 

[rubbertoe]

I'm surprised no one has mentioned this but if your running dual
38's that jetting is not correct, that looks like the single 44 on 61x cases.

I would say youd want to be at 75 pilot, 137.5 main, 1.5 needle and seat and 115g spring if your running stock flame arrestor. It would be a wise idea to contact jetmaniac for his jetting specs on that motor.

yes ,i was just trying to point op.in the right direction ,very good info right there ! my dual 38 brap-jacks 62t/x set up works great ! 77.5 lows 130 main 95 gram spring 1.8 needle seat braaaaap !!!!!! (don't have to mess with much so i had to look at my notes). hope this info helps.

 

[JMew03]

I was about to say the same. Those jet sizes are incorrect for dual 38s.

 

[Waldbjoern]

I really do appreciate all the input that I can get. But if you all were to read the entire thread, you would see that those jets and springs needle and seats has worked twice before, and when it worked all was perfect. Then it started to go bad, and it kept getting worse and worse. And that dosnt sound like jetting error. Also the jettings are from FP for that setup with that exhaust.

 

[Waldbjoern]

And for filters it's running dual tau-cetti 2,5" :Banane57:

 

[Waldbjoern]

Allright - This one is on me :thumbsdown:

I Can see that the spes that i linked is on fact not the specs i run.
In the carbs are main 135, pilot 70.

I took the info from FP's homepage, and by accident took the wrong year carbs!

Sorry the inconvenience :<

 

[Waldbjoern]

New used carbs just arrived, and i've taken the ones that I have bin using apart (also the ones that i've rebuild) and i've noticed that the membranes are bending and its like they are too big! Take a look at the pictures..





Last picture shows the old membrane (the one on the left) thats not bended, and fits right in the intended carvings. (Its from the old carbs that I just received and are going to try out, and which haven't bin used for a while.)
The membrane on the right is the new one that i've ridden with both times after the rebuild, and the ones thats bin causing me problems.

What makes the membranes bend, and is that a flaw?

 

[Waldbjoern]

New carbs were tested today and still the exact same problem - so the problem is not in the fuel line!!

 

[Matt_E]

You replaced carbs, not fuel line. Why are you ruling out the fuel line?

 

[Waldbjoern]

Cause it's all bin checked and double checked! Next thing up is stator coils..