Project Banshee...Runs but only starts and goes under throttle

[sr73087]

Alrighty then.......

No1 .need to pull at least 1 carb and see what you have for jets..

No2, I'd highly encourage you to do a leakdown test before ya go too much further......this way your not "masking" an air leak with fuel adjustments

No3. forget about anything related to a V8 lmao 

 

Ok for the main jet I have a 280. I will pull the others tomorrow.

[sr73087]

Thanks I really appreciate your help.

 

I also noticed a huge issue. They never had the choke crossover tube hooked up, which is causing a large vacuum leak. It makes complete sense on why it had to be reved and likely caused a lean issue, correct? Can I just use a piece of .25 fuel hose for that? I measured the OD and it is 0.27.

[sr73087]

I thought he meant the actual choke itself. But good call.

 

Yea I hear you, it makes sense.

 

For the leakdown, I found a nice writeup on making the tool. Is that how most people on here do it?

 

Sort of like this.... http://www.thumpertalk.com/topic/1061686-build-your-own-diy-yz250-leak-down-tester-pics-included/

Edited August 18, 2015 by sr73087

[sr73087]

perfect thanks

[sr73087]

Main: 280

Needle: 345

Pilot: 30

[sr73087]

So back from the dead. I finally got some time to get back to this. I did the leakdown and compression tests earlier today. One thing to note was both plugs were oily and when I pulled the left exhaust, there was a ton a black oil in it. Also, I fixed a major leak by the boost bottle. Which can explain the idle surge I was having.

 

Compression test

Cold

Right  115 psi

Left     117 psi

 

Leakdown

Pressurized to 6 psi, dropped to about 5.25 in 6 minutes. The tester I made had a slight leak near the gauge, so I attribute some of the drop to this. I sprayed the crap out of the whole top end and only found a trickle of a leak coming from the crankcase. Not sure how serious of a leak this is. Below is a picture of the breather after 6-7 minutes.

 

 

 

After it was all back together, I started it and it ran ok for about a minute and then died. Left side blowing alot of smoke (same as the shit load of oil).

[Deezil]

Slides in backwards?

 

Put new plugs in it

Edited September 8, 2016 by Deezil

[Larry's Shee]

Ditch the bottle !! If the carb boots aren't fucked, they soon will be !!

[sr73087]

Slides in backwards?

 

Put new plugs in it

 

I will pick up some new plugs tomorrow. Could it be that simple that it isn't efficiently burning the mixture? I know my float height is incorrect since the carbs continue to spill some fuel. Not sure on the jetting however.

 

What do you mean slides in backwards? Are you referring to the boost bottle?

[sr73087]

Ditch the bottle !! If the carb boots aren't fucked, they soon will be !!

 

Yea they are not in the best shape. Looks like you are right, most people on here are saying the boost bottle is completely unnecessary. So just buy a stock crossover tube?

 

Another thing I did notice was is there supposed to be a choke tube between the carbs? Picture attached, I do not see one.

[hoppedupandcutdown]

NEED that tube

[hoppedupandcutdown]

slide will go in the wrong carbs backwards, easy to tell from the air filter side

[sr73087]

So I changed out the plugs (gapped at .030, same as what came out). Checked the slides and they were in correctly. Not sure if the adjustment is perfect, but they aren't in backwards. Added the choke tube. 

 

I started it up and it ran well. No surge like before, since we fixed the vac leaks. It didn't puff white smoke even close to what it previously did. I only drove it around my property, but it had good power through 1st. Idle seemed very good, would not stall out like before. 

 

So now the most important issues are:

 

-carb overflows on left side (float height would be the only thing I assume?)

-clutch wants to engage when cold, even with clutch lever pressed down (Is this just adjustment or could it be something else, since it did not do this before?)

[hoppedupandcutdown]

 

 

-carb overflows on left side (float height would be the only thing I assume?)

-clutch wants to engage when cold, even with clutch lever pressed down (Is this just adjustment or could it be something else, since it did not do this before?)

Overflowing could be float level but probably a dirty or worn needle and seat. I usually just replace them if you're gonna go in and inspect anyway.

Creeping cold clutch is fairly normal. Could adjust it out or could be a grooved basket.

[sr73087]

I actually switched out the needle and seat awhile back when I first attempted to resolve these issues. The one that was in there was alittle worn though. If that is new, does it basically only point to float height since that is what is allowing the needle to open?

 

Regarding the clutch, when you say normal, do you mean normal wear? Or normal like that is a normal symptom of a particular issue?