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-   -   Picco .12 Torque 2011 sluggish out of corners (https://www.rctech.net/forum/onroad-nitro-engine-zone/606879-picco-12-torque-2011-sluggish-out-corners.html)

ProE 03-07-2012 01:33 PM

Picco .12 Torque 2011 sluggish out of corners
 
Hi,

I'm having issues with my .12 Picco Torque 2011 motor. It will be fine at the start of a race, but at about2-3 min into the race, the motor bogs down when I try to accelerate from a sharp corner. Initially I thought the motor was to reach at the bottom, but I've leaned it a lot and it still does it.
Its almost like the car go into a model where is stand for a second, and then just jumps off at pace.

And Idea?

Im also looking at the def carb settings if anyone has them please?

What temps do you run these motors at as well please?

Thanks

LOW ET 03-07-2012 01:47 PM

could it be a clutch issue?

stefan 03-07-2012 02:14 PM

I'd say it's way to lean on the bottom.

Picco carbs need to be rich on the low end needle and VERY important, those composite carbs need a few laps to heat up.

If you adjust a Picco carb too early, you'll lean it out and kill it.

Run at least 4-5 laps at race speed, before you attempt any adjustments.

Geezatec 03-07-2012 03:47 PM


Originally Posted by stefan (Post 10436058)
I'd say it's way to lean on the bottom.

Picco carbs need to be rich on the low end needle and VERY important, those composite carbs need a few laps to heat up.

If you adjust a Picco carb too early, you'll lean it out and kill it.

Run at least 4-5 laps at race speed, before you attempt any adjustments.

Agree on being rich, but could be lean also. May have to play with it on the LSN. Slowly turn LSN CW. Does it stay at idle speed? or rises then stalls? Rises then stalls too lean. Hotter the temp, the leaner it gets,

wallaj232 03-07-2012 04:30 PM

have any pics?!?!?! :sneaky::sneaky::smile::smile:
sorry for not offering any useful advice in advance:(:(

ProE 03-08-2012 10:47 AM

initially I thought it was to rich at the bottom.

I even tried the steps from the picco site
"Start leaning the low speed needle a little at a time (then repeat the reving up and idle test) and if it takes longer before the idle drops you are going in the right direction!
Eventually as you keep leaning with the low speed needle the idle will stay high, now it is time to lower the idle to get the desired low RPM. Finally richen the low speed needle half turn."

When I followed these step, I had to go in a lot on the bottom needle. Which made me think that it was to rich at the bottom, but I still had the same problem later in the day. I checked the tank seal and also change fuel lines before the last club race, but still had the same problem.

wallaj232 03-08-2012 01:41 PM

Well I had a picco JPX .21 engine and I wanted to turn the nipple on the high-speed needle. So when I would run it, after 2/3 of the tank was gone it would big down. I checked the fuel tank, plug and fuel line and got nothing. When I tightened the high speed needle valve 1/24 of a turn my engine ran perfectly. :weird:

Geezatec 03-08-2012 05:29 PM

If it takes awhile for idle speed to drop, it running too lean. What you lookin for, idle speed drops half a second to 1 second and go from there. Run a few laps and adjust as needed(LSN).

stefan 03-08-2012 09:27 PM


Originally Posted by Geezatec (Post 10441439)
If it takes awhile for idle speed to drop, it running too lean. What you lookin for, idle speed drops half a second to 1 second and go from there. Run a few laps and adjust as needed(LSN).

Sorry to disagree, but when it takes a long time to drop the idle speed, then it's usually to eich on the bottom.

If it's too rich on the bottom, you need to turn in the idle screw to keep it running and then, when you clear it out, the idle is too high and it takes a bit to load up again and drop the idle speed.

djiewie 03-09-2012 01:22 AM

Had this problem with the Picco torque going high idle. Changed the bearings and the problem disappeared. Great engine. Fastest one i have. And i also have a Murnan M3. Picco the best :sneaky: (besides the bearings though)

Try if you have sideway play on the crankshaft.

ProE 03-09-2012 09:27 AM


Try if you have sideway play on the crankshaft.
There is no side play on the crank.


Quote:
Originally Posted by Geezatec View Post
If it takes awhile for idle speed to drop, it running too lean. What you lookin for, idle speed drops half a second to 1 second and go from there. Run a few laps and adjust as needed(LSN).
Sorry to disagree, but when it takes a long time to drop the idle speed, then it's usually to eich on the bottom.

If it's too rich on the bottom, you need to turn in the idle screw to keep it running and then, when you clear it out, the idle is too high and it takes a bit to load up again and drop the idle speed.
The idling is fine. When the throttle is closed the revs drop down immediately. Its only on the track when trying to accelerate from slow corners. It I keep the refs up just above idling revs, when going around the corner, the problem is gone. Its only when I get of the throttle, turn, and accelerate that this happen. When the car is of the track after the run,and I run it on the starter box when still hot the problem is gone.

I guess I will have to strip the engine completely to check if I can see something wrong.

Geezatec 03-10-2012 08:04 AM


Originally Posted by ProE (Post 10444227)
There is no side play on the crank.



The idling is fine. When the throttle is closed the revs drop down immediately. Its only on the track when trying to accelerate from slow corners. It I keep the refs up just above idling revs, when going around the corner, the problem is gone. Its only when I get of the throttle, turn, and accelerate that this happen. When the car is of the track after the run,and I run it on the starter box when still hot the problem is gone.

I guess I will have to strip the engine completely to check if I can see something wrong.

You blowing smoke when you accelerate? Just a bit is alright. What the temp of engine at normal running. If that alright you just have to do some maintenance on the clutch you have. it sounds like the clutch shoes may need some deglazing. Small thing you may look at. Centax style clutches are sensative with dirt and glazing.

What TX are you useing?? Does have servo speed you can adjust?? Slowing down the speed of the throttle may help. and propapbly rectify half the trouble you have.

From off idle, 1/3 throttle to Idle speed stop. It drop speed right away. Try adjusting LSN so it drops so idle speed 1/2 second to 1 second

ProE 03-10-2012 10:18 AM


What the temp of engine at normal running.
115 deg C


If that alright you just have to do some maintenance on the clutch you have.
The clutch is good. the motor is not revving up. The moment it revs up, the car goes of quickly.


Slowing down the speed of the throttle may help. and propapbly rectify half the trouble you have.
The problem is only after a couple of minutes into the race, so I dont think its the servo being to fast.

Geezatec 03-10-2012 10:50 AM

115 C!!! I deal with F. 115C = 239F That says it's too lean. 180F-205F more like for temp. That's in the US where I'm at. 58F-109F i run at, 102F-109 in ther summer. If you run that hot in SA, and hot weather. try a cooler glow plug. I go a couple cooler plug when running over 102F ambient temp. This is my opnion only!!! I can be wrong!!!

Team Chump 03-10-2012 02:10 PM

Sounds like a 'lean bog' caused by fuel tank pressure dropping as the fuel comes down during a run. What brand of car are you running? Have had some fuel tanks more sensitive than others for this problem.... Would maybe try re-tuning your engine towards the end of a test run as the fuel gets low in the tank.


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