See if you can figure this one out!

[SUPERJET-113]

I'm building a 650 square nose for my kid to ride.
A lot of the parts came from my first square nose and some parts I have bought off members here.
When I finally got it all together and started it it kept back firing really bad. Was as loud as a double barrel shotgun once.

It took me a long time to figure it out. Can you guess what the problem was? :smokin:

 

[TB]

a g.i. joe stuck in the exhaust chamber???

 

[Boris]

Leaking needle and seat ?

 

[sflsurfrider]

sheared woodruff?

 

[Shonuff]

Sheared woodruff x 2?

Mouse nest in the exhaust?

 

[SUPERJET-113]

Leaking needle and seat ?

Nope! Checked and tested that.

sheared woodruff?

Nope! Looked good!

Sheared woodruff x 2?
Mouse nest in the exhaust?

No, I even ran it with the water box unhooked once to check for a f'ed up or clogged water box.


Keep guessing!

 

[D Slicker]

Its defiantly electrical..

 

[Boris]

Something stuck in the reeds ?

Mismatched stator and flywheel ?

 

[aramis]

ok, not to get off on a tangent, but the g.i. joe and mouse nests made me remember a funny story...

I had my 650 upside down in the garage over the winter, cause I had to fix a bondline crack. Got it repaired, flipped it over, put the tank and everything back in and rolled it into the driveway to fire up.

It goes "BRAAAP ting-ta-ting-ting-ting". I was like "OH #@$^%&*", then realized that the ting-ting noise was just the dog food pellets that the mice stored in the exhaust tube bouncing off my car hood...

 

[SUPERJET-113]

Something stuck in the reeds ?

Mismatched stator and flywheel ?

Nope, reeds look good. No blockage, chipage, crackage, etc.

Stator and flywheel all a matching 61X set.

 

[SUPERJET-113]

ok, not to get off on a tangent, but the g.i. joe and mouse nests made me remember a funny story...

I had my 650 upside down in the garage over the winter, cause I had to fix a bondline crack. Got it repaired, flipped it over, put the tank and everything back in and rolled it into the driveway to fire up.

It goes "BRAAAP ting-ta-ting-ting-ting". I was like "OH #@$^%&*", then realized that the ting-ting noise was just the dog food pellets that the mice stored in the exhaust tube bouncing off my car hood...

LOL, there was someone else that had that happen to them. I remember them saying it was spitting baby mice out the exhaust every couple few seconds! lol

 

[wayne]

loose stator screws?

 

[SharkB8]

Corroded lanyard switch. No spark while gas fills exhaust system, then a little spark.

 

[SUPERJET-113]

loose stator screws?

Nope! good guess though!

Corroded lanyard switch. No spark while gas fills exhaust system, then a little spark.

Lanyard switch is all good. No, that wasnt the problem!
Good scenario!

Keep guessing :thinkerg:

 

[wayne]

was the timing retarded instead of advanced?

 

[SUPERJET-113]

was the timing retarded instead of advanced?

No, stator/cases lines were lined up to stock setting.
I wished it would of been as obvious as that!:fingersx:

It didnt just backfire like when shutting it off or something, it was constantly coughing, puking, choking, back firing while it ran.

 

[Boris]

Messed/twisted up crank ?

 

[SUPERJET-113]

Messed/twisted up crank ?

Another great guess Boris!
I did get the crank used, so that was one of my thoughts too after I found it to run like crap.

I checked it to see if it was out of phase or twisted in anyway, shape, or form, but NOPE, all checked out good!

Keep em' coming! lol

 

[Boris]

I'm sure you did shorten the spark plug leads and did the simple stuff.
This is frustrating.

 

[restosud]

poor assembly?as in you shouldn't put engines together!:dead1: