96 720 leaning out on one cylinder only?

[Tims1957]

I appreciate the answers. I will check all these things. I really did come off like a shitbag and I don't expect everyone to accept my apology and I understand that. As far as the timing goes....how could it be off for only one cylinder? The flywheel piston and cylinder look great. I will read through my manual on how to check timing.

 

[Tims1957]

And sportster u are once again correct. I didn't read the article. Like a five year old a quickly looked at the pictures and the passages for each picture. So it's you I owe the apology to really. I am sorry I critiqued your efforts to help me. Hopefully at some point I can regain your respect.

 

[brian0516]

We all have our d bag days. Glad to see you owning it.

 

[AdamXP800]

I can respect that.

 

[Sportster-2001-951C-Stock]

No prob dude, I think you're well on your way to setting the fuel system up the way it needs to be.

 

[Tims1957]

So I went through the carbs and didn't find anything major..kinda dissapointing. Haven't checked the pop off pressures yet though. But here's what I did find and I'm really thinking this could be the problem. The previous owner said he had the engine rebuilt...including the crank...and it hast run properly since. Today I'm putting the lower end back together and I notice that one of the counterweights just skims the side wall of the crank case wall when it's just in the bottom cases once I set the top case on.....it is difficult to spin. So it,looks,like the crank wasn't totally pressed tight together when rebuilt maybe..but then I notice that the rod journals arnt 180degrees opposite each other. And being that it's the pto end of the crank that was ruining pistons,is it possible that the piston on the magneto side was firing at the right time but with the crank out of phase the pto piston suffered from detonation from being out of time?

 

[racerxxx]

Sounds like the crank is out of phase and you might have found your problem. To check it there is a procedure in the shop manual for checking the phase of the crank. No fancy tools needed, just two long wood dowels is what I would use. Bummer man, guess no warranty on that one...............

 

[Tims1957]

I bought the ski with motor issues real cheap knowing I would put some money in it. I'm just glad I found something wrong to point a finger at. I really didn't want to put it all back together without finding the culprit of the reoccurring piston issue.
And as far as the pop off pressures go....I'm assuming you'd want both carbs as close as possible to each other...but how close is close enough?