Just did 5 tanks through my new Picco .28. I did'nt take any notes or anything but this is what I remember about the break in.

The first tank at factory setting cranked right up, and was more awake than any other engine I' have ever seen on the first tank, good smoke, very peppy, considering, 211 degrees average

The second tank (with no adjustment) started out like a dog... the way I thought the first tank should have felt. Lots of smoke, very fat. 140-160- degrees. No second gear.

Half way thru the third went the same. So I leaned out 2 hours on the high side and was seeing steady performance running at about 190, perfect.

What I remember of the fourth tank was 207 for the first half, easily getting to 235 the resat of the half, still running good. Especially toward the end of the tank. Pulling wheelies in fact.

Today I ran tank five, no adjusting, nice running 230-240, thru the whole tank

Half way thru tank six went the same way, running great at those temp, I slightly raised the idle, then after 3/4 still had smoke, hauling #@$, I noticed a little chirping at idle, no lean bogs or anything, so I brough it in for a temp. It read 328! WOW! Shut her off.

Are these signs of an air leak?

Half Lean Syndrome?

Or are these normal break in quarks of a Picco?

Your thought are welcome

Thanks

JOSH

Im about a gallon in and running 280-290 and rich as hell,i did an air leak test and found out the OWB is leaking.

Thanks for the reply trainrobber

How do you do an air leak test?

take your engine out SEAL IT COMPLETLEY OFF SO IT CAN BLOW OUT NO AIR OR TAKE IN ANYand get the following :soap,a cup, and some good old down to earth water! then mix the soap and water and pour it around the carb and pretty much every where then turn it over a couple of times and if bubbles there is a air leak. also make sure that your header pipe is sealed off very good to the muffeler you may not think it but if there is a leak there it can cause your truck to run lean......i also like to run turbo plugs as they seal up better

[link]http://www.youtube.com/watch?v=epEGetU7NFU[/link] also i forgot to mention test your fuel tank

Awesome

Thanks for posting that video for me

I'll be watching and following it

Thanks again

JOSH

You get that Picco figured out? I will try to watch this thread, if you have problems... PM me, I might have some additional tips that will help you. Bud

Yeah, might be an air leak at the carby, very common problem but hard to detect as it usually happens at running temps. What happens is the alloy and plastic parts of the carb expand at different rates when heated, so it leaks where the plastic(composite, whatever)and alloy pieces join together. If it runs fine, then when it gets into the 200+ range starts acting up like the idle seems to hang up when you let off and temps start climbing fast, then this is prolly the issue. Either send it back for replacement/repair, or seal it yourself where the different materials join. A couple options that seem to work are a couple thin beads of red locktite ONLY where alloy meets plastic(obviously remove carb first). Put on a thin bead, let it sit overnight, repeat. Or JBweld in the same areas. I used ultra copper rtv sealant on mine, but after a couple gallons it seems to have started leaking again, so I'm gonna try the locktite first, and if that don't do it, the jb weld. Just be sure not to locktite or weld the carb into the case. Let us know how it goes.

in my opinion, i wouldn't use loctite or Jb weld, lets say you need a new carb, how will you remove it, just clean it up real good and put on new silicone [8D]

On the bell of the carb, not where the carb meets the block. I should have posted a photo with it.



I have been using CA glue on mine and so far I have not had one leak. I know of other people who run a bead of sealer around it, but sealer is easy to tear. I had recently seen a thin bead of JB Weld used. What happens is the aluminum bell expands at a different rate than the plastic carb body. That allows an air leak that only appears as the carb becomes heat soaked. Not all of them did it. I have more Piccos than any fool should have. This is an issue that sometimes requires attention.



There is your bead of silicone for the carb base.



There is your backing plate seal.



Back to the carb, the bell at the other end may need sealed too. It should be covered by the silicone boot, but they can suck air at the aluminum to plastic connection for the same reason, different swelling rates.

You may also get one that stops idling down when it gets heat soaked. The slide to carb bore fit can be so tight that the slide will get heat soaked and stick in the bore. I had one that was so bad about it, you could not push it shut with your thumb, until it cooled off, then it worked normally. I use toothpaste and apply it to the slide. I chuck the slide up in my drill and run it in and out, using the toothpaste as a seating compound, similar to the old valve lapping compound in engines. It is pretty easy to clean the toothpaste out with hot water and Q tips.

Finally, they cut the slot for the idle screw to very close tolerances. If your carb sticks, back that idle screw way out and see if it still sticks, if not, the slide is swelling and trapping the tip of the idle screw as it gets heat soaked. I chuck the idle screw up in a drill and spin it on a fingernail polishing stick or very fine sand paper. You do not need to remove much, I have also used a fingernail file with my drill.

I agree, do not weld or glue your carb to the block. If you read my previous post, I think that was fairly clear, now you have photos too. Bud

Edited as I see it was not my tip you replied to, but the guy has the right idea. I think you read something else into it. I try to catch as many of these threads as possible as a few minutes attention can save you hours of frustration. The Picco is a super engine, they just have a few areas to watch. Bud