• Welcome to RCTalk! 🚀

    Join the #1 RC community where hobbyists connect, share, and get expert advice on RC cars, trucks, boats, drones, and more!

    • ✓ Friendly & passionate RC enthusiasts
    • ✓ RC tips & troubleshooting
    • ✓ Buy, sell & trade RC gear
    • ✓ Share builds & upgrades

revo+picco 26 red dot issues

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, and others.
chickenman242

chickenman242

Hardcore RCTalk User
Messages
1,360
Reaction score
14
Points
638
Location
straya mate
RC Driving Style
  1. Bashing
hello all,i have receintly peicing together a revo with a .26 red dot that i purcased 2nd hand from a member on this forum
all went together great ,got a new fuel tank and lines also got a ths pipe and manifold and new airfilter so basically everything is brand new on the engine side of things
now my problem is that today was the first trial run and things didnt go great
i got her to start but it was idling very high and would stall as soon as i removed the ignitor,once that frustrated me enough i reset the needles,hsn 3 turns open and lsn 4.5 turns open and installed a new odonell #99 glow plug and restarted but that made little to no change as the idle got higher with little to no smoke and the temp was at 210F after running for less than 30 sec so i shut it down and bought it inside to do a full leak test........nothing i even submursed it in water and nothing, i have sealed every thing that can be sealed either with copper rtv or lucky 7 engine sealant
hopefully i can retry again tomorrow but i think its gonna be the same all over again
if anyone can see something I'm missing id like to hear your input:D
 
Compession is like new, motor has about 3/4 of a gallon through it according to the previous owner
Ill check that link out once I get home
What sort of settings should I run, just as a base line, running 30% nitro 12% oil
Ambient temp is 30c atm
 
Wow my settings were wayyy out
My fault I read in the back of book those setting and just assumed they were correct, should of asked more questions
I will reset and test after work thanks for the info
 
Fyi, 1/2 turn out from flush may be rich or lean depending on your outside temps. Flush is the actual setting.
 
ok so i reset the hsn half turn past flush and reset the lsn with the throttle at wot to 7.5 turns
now looking at the lsn the needle itself is sitting quite proud of the ball connector is that normal or have i done it wrong
sorry for all the questions i havent delt with this engine before and none of my lhs carry the .26 max at all
also can anyone recomend a glow plug for this engine it came with a odonell #99 and i have ordered a couple more but is there something else i can use if needed ,ie an os plug or somthing
 
I think I've been running the O'donnell #100 in mine.
The lsn will stick out past flush, but make sure you have the slide closed when you gently turn it all the way in.....Then count 7 full 360° turns and 1 half turn out.
 
Mccoy #8 is the recommended plug for the picco .26 max. I run them and they do fine. Any long medium plug will work. The OS #8 is a good one too. Also yes its normal for the lsn screw to hang out past collar on this mill. Also 7.5 out to 10 is the stock setting. Mine is about 7.75 out right now and does fine.
 
Stupid question but does it make a difference if you set the lsn with the throttle open or closed, the website says open but if everyone is doing it closed ill go with that
 
I've never set lsn while open. Matter if fact most of the time i do it while its idling. Very small turns at a time until she idles like i want.
 
Ok cool ill re reset the lsn, there sure are alot of conflicting ways to set this thing up
The book I got with it says hsn 3 turns lsn 2 turns past flush then the website says different again
Hopefully ill get a chance to give her another shot tomorrow
 
Does anyone know where to get an o ring kit for the carb I've tried ebay and amain but no luck
I've noticed that the outer oring on the lsn is a bit chewed , not too bad but enough for me to want to replace it
 
made a bit of progress,not much but its a start
got it to run this arvo hsn half turn out from flush,lsn 7.5 out.took a bit to start as it was pig rich but once it did it would run ok but i had to keep on the throttle or it would bog
started to adjust the hsn in the end I've leaned it by half a turn and was getting good speed and smoke,so i moved on to the lsn and started adjusting 1 hr at a time and things were going well,the idle started to creep up a bit so i knocked it down a touch and it was sweet ,good punch good smoke and idled great ,then she ran low on fuel......
pulled it in and refuel about 3/4 tank and fired it up again but it felt rich so i kept it goin for a bit and it got a bit better but then i had more problems with the idle getting sky high and had a run away for some reason,ran straight into the wifes car and broke a front carrier,fixed that and started again
it stared great but still idled high and with a chewbacca idle,checked my temps they were at about 235f so i thought that was ok but the idle was telling me my lsn was lean so i would the lsn back out 1/8 turn and had no change
the thing that gets me is there was plenty of smoke,temp never went of 245f(ambient temp is 33c) but it boged off the line and through mid range but hadf a decient top speed ,changed it 2nd and still had good smoke at wot
so i guess what I'm asking is how do i get this thing to idle consistently with good punch,i'm thinking maybe its something to do with my fuel lines being coiled off the roll bar (stock fuel line configuration) and an ae fuel primer,should i shorten then to run directly from tank to carb and try and limit the tank leaning issue??
 
thanks for that,good read ill set the idle to 1.0mm and try again tomorrow
i was reading a thread from last year about a dude having similar problems with erratic running,maybe i need to get some more litres of juice through this engine as i'm sure it only had about 3/4 of a gallon through it since new
also i was thinking about changing to a hotter plug asi also read in that thread to run a hotter plug while going through run in,you anyone suggest/recommend somthing
i'm currently running an odonnell #99 which i believe is a cold plug,i have on hand the following plugs
os#8
os a5
dynamite medium plug part#dyn2495
os lc3 os lc4
and various trx plugs
should i stick with the odonnell plug or maybe switch to another i have
weather is forcast for between 30-34c for the rest of the week if that makes a difference
once again thank for your help
 
I'm gonna throw this at you, I don't know what the weather is like in Australia compared to here in Texas but the stock needle settings were way wrong for my type of climate. That LSN was so far out I thought it was going to vibrate out, but it was the right tune. You sound like your still way to lean. I ended up taking it to the LHS when I was breaking it in and got one of the guys experienced with Picco motors to tune it for me. If I remember right I was like 5 1/2 turns out or more on the LSN. Another bit of advice is this motor doesn't like quick blips on the throttle when its cold and your tuning. Ease into the throttle very slowly :)

On the idle hang, I had issues with that aswell...I had searched alot for the issue and found that when the carb is up to temps the part where the metal and composite meets will tend to generate an air leak. Lucky 7 or some sort of sealer around this area will eliminate the issue and should eliminate the idle hang.

On the throttle sticking, make sure you set your throttle end point so the carb slide only opens as full as it needs too, if you go past that it will begin to bind and cause the slide to not close fully. Getting a good return spring on there will help alot aswell.
 
Last edited:

RC Builds

Back
Top