Picco Problems
 

I have a Picco .21bas 3 port, now the problem is when I rev it seems ok. but when I put it on the ground it acts like it wants to bog like its gonna cut off but doesnt. it seemed fine yesterday I had no problems. It has no problem at higher rpms just when I slow down to turn. could i have a air leak and how do i find a air leak or could it be my fuel lines? any help would be great.

it may have some debris in your fuel passages...take the needles out of the engine, take the HSN stack off the engine and clean everything..I have seen this when a piece of O-Ring gets caught in the fuel venturi...

ok I will check that asap

Sounds like a lean bog. Richen it a bit and see if it gets better.

also piccos are know to get air leaks on the carb where the aluminum and composite part meets up. we ran a bead of JB weld around the seem where the two meet up and that problem was fixed, havent had trouble since.

i can send pics if you need them.

Pics would be nice i never had to seal a engine before

It's not the engine you need to seal. Like he said, it's the carb. A lot of Picco carbs are both aluminum and plastic. Where the two parts meet can sometimes have an air leak. Just seal up that joint with JB Weld or threebond or something like that.

oh ok got it

usually if the carb is leaking ( which was actually quite rare )the problem would come on slowly as the temperature climbed....it would start as a tendency for the RPM to hang a little going off a jump, similar to having a large idle gap...and the issue would get worse and worse the higher the temps got, and unfortunately this issue would create more heat on its own....so the engine would run great cold, but would really start acting up once everything was fully heat soaked....Then if it was left to cool down the issue would be gone when re-started ...

When i have seen a Picco start suddenly start sagging on acceleration for no reason its almost always a blocked fuel passage...usually its a tiny piece of o-ring from the HSN that has made its way into the fuel passage..I find this happens more when people try to count turns on the needles, as they are always screwing the needles in and out and it causes the o-rings to take a beating...To fix i just take the entire carb apart, pull all the needles out of the housing, flush with nitro spray and a air compressor and put it all back together....

Now he could just have a bad tune, but if this symptom just suddenly appeared and no amount of needling will make it go away, there is a good chance the fuel passage is blocked...

Im gonna trust maximo's word and try his method first, not that the other ideas wont work, I have learned to take his word. :nod:

:nod: when it comes to Picco's there is no need to ask anyone else

ours didnt do it like that, ours would do it worse cold. it would hang off jumps and also do weird things sitting at idle. JB weld and the problem was fixed, have ran it 5+ gallons since then.

but i kinda think your bottom end needle is wrong, seems like some tuning issue to me.

by the way, what plug are you running?

Ok got it fellas Maximo was right simple cleaning and flushing of the carb and its back in action. Thanks a lot

I will also seal the carb with the JB Weld just to be on the safe side, thanks for all you input fellas.

Im running the OFNA #4 hot plug and Odonells med-hot. Does anyone suggest a plug to run?

don't use JB weld...it makes more of a mess then anything, and tends to not adhere too well to the plastic side, it wont take long for it to start leaking under the bead..... best bet is to leave it alone... only seal it if it matches my description of the issue...and when the time comes use either a thin bead of CA glue, or a coating of lucky 7...I have tried the JB weld before and it isn't the best solution....

And before the peanut gallery comes here and says JB weld worked for them, let me remind you that you have owned 1 single Picco, I have worked on and tuned hundreds of them..... No intending to to be rude by saying that as I respect everyone's opinion , but Picco's are sort of a specialty of mine...