tune question brand new mt wont fire

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wwbiker

wwbiker

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hey my truck was running ok but i little ruff so i went to tune it according to this link. https://www.largescaleforums.com/show...06&postcount= no it wont even sputter or fire up, i tryed to get it back to the original settings but it wont fire. i am know alot about gas engines and im getting spark and gas but wont start. what is the factory low and high speed settings? someone help please im only on third tank!!
 
1st your settings may be too rich.

Put your L at 11/4
Put your H at 11/4

This will be leaner then you want but it will get it started.
Keep it running and do the following:
Form there you can richen the L until the idle starts to go to far down and it wants to cut out. Lean it about a 16th and start there.
Now richen the H to 11/2-13/4 and start with that there.
Follow ESP's recommendations from there.

Note:
If its flooded you need to take the plug out and dry it off. Take the buggy with the plug out and flip it upside down and pull the pull start about 10-15 times to allow the gas at the bottom of the case to rise and exit the exhaust or the plug hole.
Now try pulling it over without the choke on.
 
i have tryed both of the above, i have excellent spark, good fuel, good compresion, and fuel getting to the plug ( not to much so i know its not flooding) i see no reason what so ever while it shouldnt at least sputter, this is really starting to annoy me!!!!!!!!!!!!!!!!!!
 
when i turned it over probabaly a 1/2 to 1 oz of drak oil gas came out before i even pulled starter rope, so i was like yes that must be it, then i put a brand new plug in checked for spark then srewed it in and nothing to sputter or nothing:no:
 
Trip said:
Did you pull the plug out to see if it is covered in gunk?
Click to expand...

i pulled plug had a little gas on it not gunk and not enough to make it flood out, i have decent experience working on engines in dirtbikes etc... so i some what know what im doing, and i have never seen anything like this it should fire, ive tryed almost every tuneing option please is there something im missing!
 
If you have all of those things present then there is no reason for it not to fire up, even if it was tuned badly it should at least pop a little.

Could be the coil is failing under compression and needs replacing...have seen this before with exactly the same symptoms you mention.
 
The motor will not "push" out the "sludge" unless you have a plug in it...It needs the compression of the motor to push fuel/gunk through the ports.

So you need to put the old plug in it, flip it upside down and pull the pull start a few times... Pull the plug and look at it..

Is it covered in poop?

A cheap and easy way to remove gunk is by using WD-40, Carb cleaner or Brake cleaner. Spray it down the throat of the carb, liberally (make sure the spark plug is out!!!) Pull the recoil a few times then do it again. Do this 3 times, put the old plug back in and pull it a few times... Take the old plug and set it aside. It will probably be coverd in gunk...

Pull the recoil at least 10-15 times and get all the "Cleaner" out of the motor...

Install a new plug. Prime the fuel bulb, pull the choke and give it a few pulls... When the motor pops, open the choke and pull 3-5 times... It should start. If it doesn't let us know..

The gunk you have in the lower end can be cleaned out, but if you don't clean it, it will never start. All it will do, is foul the plug...
 
Do you have an air compressor? If you do, make sure your top end is clean so nothing can blow in the top end. Take the plug out, tip the model over, pull the throttle wide open, pull over the motor 15 times upside down. Now take your piston and put it to the bottom of the head. Take your compressor and spray air inside for about a minute. Spray off the plug with the air. Now reinstall and DO NOT USE the choke. Make sure the choke it not closed. Pull it and see if it pops.

We all know your frustration!
 
Ducky said:
If you have all of those things present then there is no reason for it not to fire up, even if it was tuned badly it should at least pop a little.

Could be the coil is failing under compression and needs replacing...have seen this before with exactly the same symptoms you mention.
Click to expand...

is ther anyway to test the coil under compression???
 
Trip said:
The motor will not "push" out the "sludge" unless you have a plug in it...It needs the compression of the motor to push fuel/gunk through the ports.

So you need to put the old plug in it, flip it upside down and pull the pull start a few times... Pull the plug and look at it..

Is it covered in poop?

A cheap and easy way to remove gunk is by using WD-40, Carb cleaner or Brake cleaner. Spray it down the throat of the carb, liberally (make sure the spark plug is out!!!) Pull the recoil a few times then do it again. Do this 3 times, put the old plug back in and pull it a few times... Take the old plug and set it aside. It will probably be coverd in gunk...

Pull the recoil at least 10-15 times and get all the "Cleaner" out of the motor...

Install a new plug. Prime the fuel bulb, pull the choke and give it a few pulls... When the motor pops, open the choke and pull 3-5 times... It should start. If it doesn't let us know..

The gunk you have in the lower end can be cleaned out, but if you don't clean it, it will never start. All it will do, is foul the plug...
Click to expand...

i spent 2 hours today doing that, no gunk came out only just the carbcleaner and wd 40, the engine is only on second tank, is it even possible to have gunk down there allready??
 
wwbiker said:
i spent 2 hours today doing that, no gunk came out only just the carbcleaner and wd 40, the engine is only on second tank, is it even possible to have gunk down there allready??
Click to expand...

You posted earlier, that you had some dark oil coming out of the plug hole. That was the gunk I referring to.

How bright is the spark? If it's too bright, the plug could be fouled. If you know dirtbikes, then you know, once a plug is fouled it's junk. All it takes is once.
 
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I really don't know... Out of the 3 motors I've had, if it takes more than 5 pulls to start them, I should put some gas in the tank.. I've had great luck with these small engines.

I wish I could be more help! Is there a small engine shop around your area, someplace that works on lawnmowers and chainsaws? They may be of more service than I. After all, these motors are just fancy weed whacker motors..

Sorry man, I don't know.
Trip..
 
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