goneracing_83

OK i got the truck used and i cant get it started for the life of me. its a Firehammer with stock engine. here is what i have done. i tried to run colman fuel with 2 cycle oil. 25:1. didnt even pop once. so i dumped that out went and got some pump gas and some more 2 cycle oil. mixed it 25:1 and STILL nuttin. went and got a new plug Had the old torch plug in it and i got a coulpe NGK CMR7H plug. i have my needles set as follows..... Low 1 turn High 1.25 turns. im getting gas the plug is wet. when i checked for spark for the 100th time. im lost here. could some one please send me in the right direction???? i havent ran this truck yet bc i need to get things for it. and i was really hopeing to run it this eveing bc it is nice out.

thanks

TJ

clubin

Compression is very important, if you have spark/fuel/air. It should run providing you have good enough compressoin. I tried colman fuel once and I couldn't get mine to run either. Fresh fuel, and prime the bulb to get some of the fresh stuff in. Are you experienced with these BIG toys?

goneracing_83

not really with the rc world but i can tune a weedeater and what not i dont get y its not even trying to pop. this is my first large scale truck and im gettin a lil well upset at it right now. i have fuel air and the compresstion well when i put my finger over the plug hole and pull it over i cant stop the air from leaving the cyilnder.

clubin

Did the seller say it ran? Air filter over oiled?

Flip the model up side down and give the recoil a couple brisk yanks. Just to blow out any excess oil there may be in the cylinder. Warm the plug up a bit with a propane torch, or better yet install a fresh plug if you have one. Choke open/closed?

goneracing_83

ya he said it ran. he ran it before he posted it on RCU to make sure it ran. it has a cone filter on it and i got the cleaner can and the reoil can and just put a medium mist of oil on the filter so that shouldnt be a problem. i have tried to start it with out the filter too just to make sure. i will give that a try quick and see if it will fire on my last new plug i have. my needles should be ok where they are right? just want to make sure

LSALLOY

My Feedback: (1)

check to make sure the kill switch is not pushed in. Everyone forgets to look for this when it does not start.

clubin

How should I adjust the jets on a Walbro Carburetor (WA-167 / WT-603 / WT-668 / WT-257 / WT-813, etc)?
These carburetors require regular adjustment to ensure peak performance, and also to avoid an unsafe lean condition, which can prematurely damage your engine. If you find your top-end RPM's have fallen off a bit, or if you experience lagging or surging, it is probably time to re-adjust the carb jets. To ensure max performance and engine life, follow this procedure:
1) Locate the low and high RPM jets on the side of the carb - they are usually marked with a L and a H. Turn both jets completely CLOCKWISE ( to the fully closed position).
2) Rotate the Low jet counter-clockwise to 1 and 1/4 turns open.
3) Rotate the High jet counter-clockwise to approx 1 and 3/8 turns open.
4) Now, start the engine. You may need to turn the Low jet slightly one way or the other for the engine to start.
5) Adjust the Low jet as desired until the idle is where you like it. Turning clockwise ("CLOSING" THE JET) will produce a higher idle, and counterclockwise ("OPENING" THE JET) will produce a lower idle (and eventually flood and the engine will kill, if you turn it too far).
6) Open the throttle lever to full blast. Adjust the High jet until you get maximum RPMs. Note: this will probably be REALLY LOUD. Listen for the highest-pitched whine to tell you where max RPMs are hit. AFTER YOU FIND THE MAX RPM SETTING, TURN THE HIGH JET COUNTER-CLOCKWISE ("OPEN" THE JET) APPROX 1/16TH OF A TURN TO ENSURE YOU HAVE SUFFICIENT GAS/OIL MIX TO COOL THE ENGINE PROPERLY.

Note: The above are just general guidelines. You may need to adjust both the H and L screws once you begin riding, depending on engine loading, altitude, humidity, etc. The trick is to find settings that work well for you, and stick with them.

Here is some helpful information regarding common carburetor tuning problems:

If your engine stutters at full throttle and cannot reach full RPMs:
The high jet is too far open. Close the jet by turning it clockwise slightly, and then ride-test. If no improvement, repeat until desired results are achieved. Once you have found a workable setting, open the jet approx 1/16 of a turn to ensure sufficient fuel/air mix.

I copied and pasted this from another forum. Very useful info.

If your engine bogs out when transitioning from low speed:
The high jet is too far closed. Open the jet by turning it counterclockwise until you are at least 1 1/2 turns open, and then gradually close the jet until performance is as desired. Poor engine compression, blocked exhausts, and very heavy engine loading can all also cause bogging.

If your engine idles very fast and kills if you attempt to slow the idle:
You may have an air leak in your intake. An easy way to check for leaks is to spray the intake manifold and area surrounding it with WD-40. If the idle changes after you spray the WD-40, there is an air leak. Common areas for leaks are between the manifold and the cylinder, and between the carb and the intake manifold. Inspect the manifold, carb gasket, and intake gasket for cracks or other signs of damage, and replace if necessary.

If your engine idles but then slowly kills:
Your low jet is too far open. Close the low jet by turning it clockwise until a stable idle is achieved.

goneracing_83

i have spark tho. and its bright enough for me to see it in the sunlight. so it cant be the kill swich bc the kill switch stops the spark right?

clubin

If you have spark, that is a good thing. Read through the stuff I posted.

goneracing_83

the funny thing is tho clubin is that thats where i started from and i have gone both ways with the low needle and it still wont start. i do 1\8 turns in my adjustments and not even a pop. i dont get it. the thing that is really erkin me is that i had the engine running my self on the bench shotly after i got it now it wont even pop. dont get it.

morespeed

go get a can of starting fluid and sqiurt it in the air filter in take,pull it few times and seee what happens. then come back and explain what it did. this will people give you a better answer.

clubin

You primed the bulb a bunch of times to get the camp fuel out of the carb? Changing to that fuel requires some different settings on the carb.

You had the carb apart? The bulb fills itself easily? If you remove the top line on the carb and prime the bulb, fuel squirts out the top? Maybe if you removed the carb you mixed up the fuel lines?

goneracing_83

well since i had the carb apart and NO i didnt hurt anything but since i had the carb apart all the fuel in it was gone and when i put it back on the truck i only had to press the primer a few times and fuel was there . and yes when i push the primer fuel comes out of the nossel like a water thru a fire hose. i might just have to get some starting fluid and see if that works like suggested above

goneracing_83

well looks like i will have to wait till tomorrow to see if starting fluid works. wife wants to go out tonight. GRRRRRRRRRRRRR. i wanted to get my RC runnig yet tonight so i can show the guys at work. they really want to see it run. as so do i. LOL well thats married life i guess LOL. thanks for all the help so far guys.

goneracing_83

well guys i have came down to the idea that the gas that one of my coworkers mixed for me is too rich on oil. i cleaned the old torch plug off with some brake cleaner and put it back in and with out choke it wanted to run since there was some brake cleaner still on the plug. so im going to dump out the mix and start over. what i think happend is that he put mixed gas (50:1) into my gas jug and then added my 5 oz of oil to it. i looked at the mix in my tank and it is really dark! i cant see the bottom of the tank and the tank is half full. so I'M going to mix my gas this time and see what happens. if that works then moral of this forum is DONT LET YOUR FRIENDS MIX YOUR GAS!!!!!!!!!!!!!!!!! even tho if that is the reason it dont run i still have learned alot from all of you. i will let you know what happens tomorrow after work.

morespeed

GR83
look i hope i didn't mislead you, but starting fliud is NOT going to fix it. it will give us a starting point cause if it starts up and then dies with it. then it's your carb. maybe

morespeed

GR83
NEVER MIND, SORRY DUDE. for that last post. i just reread yours and you said it DID START with the rag trick. sorry. your close to running it now.

goneracing_83

Morespeed, its ok i was kinda leary about useing staring fluid in the sence its a VERY dry burning fluid and could score the cylinder wall ( depending on how much is used ) but ya it did fire on the brake cleaner that was still on the plug so im going to try to mix MY OWN gas and see if that makes a differance. if not then i have a carb probelm. thats the only two things i can think of. thanks for the help tho

TJ

willig10

A couple of things.

1. Since you had the carb apart did you ensure the diaphragms were put back together the same way they came off? If the diaphragm (reed valve) is put back on backwardsit will not run.

2. If the carb is mounted to a phenolic (nylon or plastic block). Make sure you didn't run the screws in too much. If you really torqued down the screws the length of the screws can bottom out and actually push the block away from the cylinder head. Overtightening the screws can crack the block and caause an air leak. Check all your fuel lines for integrity and the block for cracks.

3.Iwouldrun 32:1 mix if you are using a gas engine. The bearings will like it and although you might get a little smoke from transition from idle to full throttle.If you havethe engine tuned properly(low end to high end) it will not be a problem withfouling the plug.

Hope this helps.

Glenn

splcrazy

if your co worker mixed in the wrong fuel oil mix then the entire tank with the carb needs a good flushing out , empty out the tank and put in a bit of fuel in the tank with NO 2 STROKE OIL , then un clip the return line from in the fuel tank and point it away from your RC and keep pressing the primer bubble untill its running clean , when you done that put the return fuel line back into the tank , then open the fuel tank and empty out the tank , and refill the tank with properly measured 2stroke oil and petrol, and try starting it again , if it still does not start your carb needles are out of wack keep playing around with the carb needles untill you get the engine to pop then carefully continue to fine tune the needles untill you get the engine to stay on, you might need to keep checking the spark plug cos its gonna keep getting wet with fuel untill the carb is tuned so make sure you blow it dry in between pulls.

goneracing_83

thanks SPLCRAZY! i did that and got all the NASTY gas out of the lines and carb by useing the primer. NOTE: to get the gas line back in here is a tip. use either a bench grinder or a really sharp knife to make a point on it clean it up and use some kind of lube. i just used gas. and it will slide right in. now after i got it all cleaned i put my new mix in and it still wouldnt start. the top of the piston was pretty damp so i closed the needles all the way and tried to start it and it fired up on the 2nd pull. i continued this til it wouldnt start anymore. then opened my needles back up and with out choke it fired up on the 3rd pull. now i have a different problem. My rear end (diff) is slipping. going to start a diff thread for that. thanks for everyones help. hope this helps other pple too.

TJ

goneracing_83

well took my truck to my dad bc it wouldnt idle right and found out that the diafram that is under the primer bulb was well bad. it didnt sit strait anymore and was holding the needle open so there for was flooding the engine out under a idle but anywhere off idle it ran good. well got a new diafram and now it starts ALOT easier and idles really smooth too. now i hope a friend of ours (dad and i) can weld my dogbone up and hope it holds up long enough to get it fine tuned and then off to the or a bash ground and see what it can handle...LOL thought to put that in here too. my dad has told me alot about these carbs so why not share with fellow members that may run into this problem.

TJ

devo208

i'm kinda having the same problem i'll read some more and do some checking and let yall know tomorrow.

goneracing_83

ok. if you still have'n problems im sure we can get you up and going again. keep us posted

devo208

Well i did what yall said i took the LSN and the HSN back to factory then leaned the low end down a little bit more and it started up i adjusted the low end and now today i'll adjust the high end. THANK YALL FOR YALL HELP. FS racing 35cc 4wd truggie. check out some of my vids. on youtube.. http://www.youtube.com/watch?v=JzynCAckm7k http://www.youtube.com/watch?v=ZoQ3ykBuAQo