Picco .40
 

I have a Picco. 40 engine that I am going to run on a Tsunami pattern plane. All of my other engines have muffler pressure to the tank. This does not have a tap for muffler pressure on the muffler. Does anyone have any experience with this engine or its clone, the Skyward .40? Does it need muffler pressure? The carb throat seems pretty big to run without it. Obviously, it runs very well on the test stand.


Max[8D]

RE: Picco .40
 

I have the skyward .40 and my muffler has a tap, I would suggest adding one to your muffler. Even if you can tune the carb without pressure, it will hold a needle setting better over the duration of the flight with muffler pressure IMO.

RE: Picco .40
 

You need pressure for the tank unless you plan on keeping it stationary like your bench test stand. Drill and insert a fitting close to the exhaust port. These are great engines. Picco is strong than any Skyward because the carb is more aggressive/larger bore than the Skyward. I got 17,500 rpm on my Picco 40. The only Skywards I had were 60 size. They really last a long time.

RE: Picco .40
 

Guys,

Thanks for confirming my suspicions!

Max

RE: Picco .40
 

If it is the same Picco muffler mine had, the weld between the exhaust collet and the muffler can may be a weak spot. I don't recall how well I balanced props in the mid '80's nor how rigid my engine mount was, so this might not be pandemic, but I recall breaking two at that point.

RE: Picco .40
 

Yep, they're weak there. JB weld, drilling and installing screws, using wire to hang on to it after it falls off, I've seen it all done.