mrlee2071

Has any one had a problem with the carb slide sticking in the wide open positon? I was just finishing my break in on my sh 28 (5th) tank, the hurricane was approx 15 feet away going about 20mpg on the black top when I bliped the throttle, it stuck wide open and accelerated into a curb. Total devistation. [&o] Anyway, opon examining the car I noticed that the carb slide was stuck wide open. Very hard to move in and out. Radio is functioning perfectly. No dirt in the carb. Fresh batteries. It's a disaster and broke my heart as well as my new car.

Any ideas?

thanks
Lee

ehroof

i have never had that happen to any of my sh engines.

mrlee2071

Is there anything in the carb that could cause such a problem? Maybe something that would back out. I have not taken it apart yet as I want to talk to RedCat on monday before I start dissasembly.

Thanks ehroof

ehroof

maybe the idle screw? try taking it out and see if it is hanging up still.

mrlee2071

I'll try that, Thanks ehroof

ehroof

anytime brother, we'll figure it out.

bash_N_corn

I read In earlier posts on this forum there was a problem with the slide sticking.. they said they were sanding down the screw a bit....Ill see if I can find it..

Here it is....

Now when everything is working a Picco carb is much superior to a SH or LRP carb ....... Picco carb s adjust easy and hold their tune very well.....But they are prone to 2 very common easy to fix issues....

1. the LSN slide can sometime be a little sticky and be prone to binding ... It seems the end of the Idle asjustment screw is a little too big for the guide groove cut into the slide bolt...So I sand down and smooth out the end of the idle screw, giving it just a little extra clearance...Sometimes you willa lso have to fine polish the inside of the slide barrel as well............ All in all its not really anything major, Picco just has the tolerances a little too tight and the slide can bind when the metals get heat soaked and expand..90% of the time its just the end of the idle screw needle being too large for the groove int he slide bolt....

2. Second issue with the carb is something very few people know about, and has likely been plaguing Picco motors for years...... Picco carb s are built using both composite and metal parts..... It seems that once the metal parts in the carb get heat soaked the seal between the composite body and metal end cap starts to leak...causing a very erratic and hard to detect air leak......This airleak is only present when the carb s metals get heat soaked ( 200 F), at room temps the carb s hold their seal well......... This makes this type of leak extremely difficult to detect.......... You will see many people say they fire their Pico up, it runs great for 1 tank, then all of a sudden the tune goes all weird, the engine will "run on"..and the bottom end will be impossible to tune.................. Then when you let the motor cool off the tuning comes back to normal again............ Unless someone knew what was happening this would make the motor impoissible to tune.......... Its funny but this problem has obviously been plaguing Picco for quite some time, yet nobody has figured out the real problem...... This summer my P7 was doing this, and I lost alot of hair trying to figure it out...........2DLST had this issue with his P7, but a little sealant later and the motor is running like a champ...So far its been 50/50 for us.... half leak, half don't...which says there are alot of poorly tuned Picco 's running around LOL !

All I do to fix this is apply a bead a sealant around the seam of the end cap and carb body, as well as a bead between the lower carb neck and the main carb body.... basically seal between the composite and aluminum ..... I Use JB Weld, Threebod 1211, or even regular silicone.... It is possible even a bead of CA glue would seal it as well

Once a person seals the carb and smooths the idle needle some these Picco 's are a dam sweet running engine........massive power, stupid easy to tune... I'd say the motors are likely easier to tune then a Mach, as Picco 's are not prone to loading up at idle, so the LSN is amazingly easy to dial in......

When you consider the Picco 's massive power output and Italian metallurgy and low cost having to tweak a carb a little is a very small price to pay...These motors really are fantastic when you know how to handle them

< Message edited by supertib -- 12/24/2007 9:09:43 PM >

(in reply to ttoks)
Report | Post #: 3

mrlee2071

Thanks For the informatin Bash and ehroof, as this is a brand new motor, I'll give Redcat a call and see of they want to look at it before I start taring into it.
The reason I bought a Redcat is because of this forum and the support from experts like you.
Thanks alot
Lee

bash_N_corn

Hey Hey Hey...... Be careful who you call an "expert" LOL Just glad I could help!

tommie!

On my monsoon the idle set screw tip broke off locking the engine wide open...I was really lucky not to smash it to a pulp but the engine was toast afterwards. I keep it doing a burnout for like a minute until it flipped onto the roof and died.

motodude11

My Feedback: (1)

wow that is truly horrible, sorry for your loss guys I'm crying for ya