woodburner

Guys,

I'm running a new OPS 60 Ursus with a Perry carb... lotsa power but it just won't quit even with a fully closed carb. There are no signs of air leakage anywhere..

Any hints?????

Thanks!!

a70eliminator

I have a perry carb that developed a crack at the mounting base from one of the set screws contact all the way up to the o-ring, it had all sorts of running issues, pop off the E-clip and pull the barrel assy and inspect all the o-rings.

earlwb

If you put your finger over the carburetor inlet and block it off, does the engine still run? If it stops when you block the carb off, then the idle speed screw needs to be adjusted out some more so the throttle barrel will close more.

Otherwise:
Yes like A70ELIMINATOR stated the carb body spigot might be cracked or the O-ring sealing off the base of the carb isn't on there snugly or tight. You need to lock the carb down while pushing down on the carb so it compresses the O-ring a little bit.
It might be sucking in air through the front bearing on the crankshaft too.
I have seen engines suck air in past the throttle barrel if it didn't fit quite tight enough as well. That happens with most any carb too.

3136

I saw one bloke who had a problem like that and he just threw a rag at it to stop it each time.
I saw it and said "are you serious, that's how you stop your engine is it?"
He said yeah so what! I've been doing it for ages, so **** off.

Cyberwolf

My Feedback: (4)

Sorry not related to the post
I seen a guy throw a ball cap at a G-62 not once but twice trying to stop it , Needless to say it didn't work but it however did cut the brim off both hats and they became beenys. Meanwhile in the pits when we got done rolling around from laughter I walked over with some needle nose and pinched the fuel line which takes longer than one would think on a gas engine *L* I think back to that day and kick myself for not having a camera, folks would pay to watch the likes of that guy.

I agree you do have an air leak some place. One thing that has not been mentioned is the back plate check to make sure the screws are snug.

aspeed

Some motors have a small hole or slot in the crankcase going from the carb inlet to the front bearing. This is to suck the fuel that would leak out the front of the motor. Sometimes this is enough of an air leak to give an idle problem like you have. You could check for this and plug it up maybe, it would require disassembly, maybe removal of the front bearing and epoxy that may come off later though.