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-   Onroad Nitro Engine Zone (https://www.rctech.net/forum/onroad-nitro-engine-zone-71/)
-   -   STS .28 pull-start engine (https://www.rctech.net/forum/onroad-nitro-engine-zone/59523-sts-28-pull-start-engine.html)

jfc_tech 07-17-2006 04:23 AM

on behalf of myself as a STS user, i acknowledged yer problem. im sure STS is working on it.

pullstarting: this is how i do it and also as adviced by Dino:

check the page 7, post #209. here

hope in anyway gonna help u. :nod:

savagegarden 07-17-2006 09:20 AM

i have a problem
as soon as i want to tune the LSN needle the engine starts to run in high rpm's well not immediatly but the engine
help me out here please

Artificial-I 07-17-2006 09:29 AM

Did you try lowering the idle via the idle screw? Also leaning the LSN will make the engine idle higher.

savagegarden 07-17-2006 09:56 AM

i tried everything but i don't think you understand what i mean
it starts acting funny like it is running lean and very hihg rpm
then when i hit the throttle it runs great again
when i go WOT on a parking lot and i let go on the throttle the engine revs high
strange

Artificial-I 07-17-2006 10:02 AM

Well I understood as much as I could from what you wrote. But yeah from what you explain now it sounds like your LSN is too lean or idle is too high. Try richening it and go from there. STS motors kind of like a rich bottom end.

What kind of plug and fuel are you running on the motor. Id still also try to get that idle as low as possible.

savagegarden 07-17-2006 11:05 AM

i run tornado 20 % (the new one they make special for monstertrucks and buggy's, has more oil in it)
the plug is an OS 8

i have just put a new carb on the engine because i had a lott off trouble with the old one (could get it to tune either, even after i changed the o-rings)

here are some pics (i hardly even touched the LSN)

http://i69.photobucket.com/albums/i7...h_DSC00005.jpg
http://i69.photobucket.com/albums/i7...h_DSC00004.jpg

jfc_tech 07-17-2006 08:05 PM

i noticed u put it on savage..great.
anyway, whats yer HSN /LSN?
mine at HSN 2T: LSN 4T. run great. and yes, STS 28 likes to have a rich bottom end.

Car Breaker 07-20-2006 10:57 PM

I have a problem with my D28M, it is the pull start, the string of the pull broke on its own not long after I fire up the car, I didn't know what happend but often time just after a few tanks of fuel, when I examine the car, the pull is gone, I like pull start as a basher but it keep broke on me. this is the fourth that break with no clear cause

jfc_tech 07-21-2006 01:41 AM


Originally Posted by Car Breaker
I have a problem with my D28M, it is the pull start, the string of the pull broke on its own not long after I fire up the car, I didn't know what happend but often time just after a few tanks of fuel, when I examine the car, the pull is gone, I like pull start as a basher but it keep broke on me. this is the fourth that break with no clear cause

try dino advice here pg 7, post #209.

mine still original. :nod:

simonh 07-30-2006 02:39 AM

Breaking in STS .28 - Can't Start - Factory Needle Settings??
 
Ive just bought myself an STS .28 and am having trouble getting it started for break-in.

I read here that they are HSN - 2 turns LSN 3 to 4 turns. I set it at these settings but it refuses to start unless the needles are just about all the way out.

I've sealed the engine (carby, backplate, and fuel nipple) and have got the needles just about all the way out.

It pretty much refuses to start unless the needles are just about all the way out.

Once they are all just about all the way out it fires up, and spits lots of fuel as expected.

Will these settings improve with time, or am I missing something here?

Does anybody know any tips on getting it running easier?

jfc_tech 07-30-2006 04:18 AM

sorry for the late reply. yes thats about the correct HSN/LSN factory setting. it does happen like that depending whats yer outside temp.

dont worry as long as it starts. keep small increment of needle turning clockwise after every tank. like 1/2hr turn. FRom what u said your HSN is all the way out it shud be really rich. but its ok for run-in the engine.

my final needle at 35degree Celcius outside temp end up at HSN 2T LSN 4T.

Artificial-I 07-30-2006 05:47 AM

Yeah 2 out on the HSN is wayyyyyyy to lean if you ask me. Make the needle flush on the HSN and make the lsn poke a bit from the brass throttle linkage on the lsn.

In reality you shouldnt even touch your motor from the factory as thats where its set....it can be off , but not much and thats where your user input comes in to adjust it a bit to your environment , glow plug and fuel.

If you can get it to fire....thats a correct setting and at least close to it. This is why you shouldnt really listen or worry about factory settings. When you goto tune a motor you want to set it to have good smoke , cool running (at least not overly hot) and lots of power.

As for break-in you want to set it as rich as possible , without making it want to shut off all the time.

simonh 07-30-2006 06:57 PM


Originally Posted by Artificial-I
Yeah 2 out on the HSN is wayyyyyyy to lean if you ask me. Make the needle flush on the HSN and make the lsn poke a bit from the brass throttle linkage on the lsn.

I thought 2 turns for teh HSN was too lean, as it was a fair bit below the brass housing. So I made it flush and even set it 2-3 turns further out. As for the LSN, it was screwed just about all the way out of the brass housing.

Got it firing consistently, and have been using the heat-cycling method to break it in. Had about 5 runs of getting it up between 80-100C (around 3 mins runnig normally), and the needles are slowly moving in. Each new run I have had to turn the needles in a bit to get it running. The HSN is now flush, and teh LSN is about 1-2 turns out from flush.

So hopefully a few more heat-cycling runs and it will be firing more consistently. Making sure there is plenty of smoke. Thanks for the advice!!

jfc_tech 07-30-2006 07:40 PM

yep usually 2T out HSN is waaayyyyy too lean. but as for my case, its the right one. i even gone thru that setting for 45minutes Main. no problem. it even got light smoke on the straight top :nod: as i said, dont follow others setting ... racing tune i mean. with different outside temp & humidity. definitely diff from every individual. unless u live near me.

for engine run-in, as usual, as long as it start & the idling is good for run-in..then thats the tune u want. im not saying u shud idling it. no no no. use whatevr method u favor, either the WOT style or the manufacturer recommend. its your engine after all. but keep it rich. really rich. even u use WOT, the vehicle wont move. best to clear everything inside the engine.

all the best. im sure u gonna enjoy the engine after the full run-in. :nod:

simonh 07-30-2006 08:38 PM


Originally Posted by jfc_tech
use whatevr method u favor, either the WOT style or the manufacturer recommend.

What is WOT method for breaking in??


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