wont start

[tarzan13]

My new baja wont start anymore.
i ran my first full tank when it was 3/4 empty it started to not run idle.
it would stall if i let it sit for 5 seconds tried to tune it but couldnt stop the stalling.
so i put it back to where it was before still not good.
I have to put trottle at half open to get it started.
i put a full thank of gas and still nothing it still stalls.
tried tighting carb and exaust.still no go.
it started a couple of time after that but now it wont start at all.
tried setting to factory default 1 1/4 low and 1 1/2 high still wont start.
can anybody out there give my some pointers would realy apreciate it.
Im used to tuning chain saw but this little motor is really hard.
spark look good.
need help please.

[mradlin]

Here's what I would try first. Change the spark plug (sometimes they can just foul up for no reason. Pull off the fan cover on the engine and check your coil to flywheel gap (if you have to adjust it make it the width of a business card) Also check your gas cap and make sure the vent plug is not plugged up with dirt or whatever. Good luck with it and let us know about your progress!
Mike

[VertigoPerformance]

When you play with the low end needle you almost always have to adjust the idle screw (the difficult to get to screw behind the roll bar) have you touched this screw yet?

[Rock Concepts]

redo the check list and make sure all is tight, take the plug out to see if it has spark. is the plug wet or dry make sure your air cleaner is clean. air, fuel, spark it should run

[Akela]

try turning your idle screw all the way in... yes I said all the way in! Richen up the low end screw some more. Get it to run in, then when you've got a few more tanks through the motor start to lean out the low end and then re-adjust the low end screw. But always first make sure that you have good spark and that your air gap is set right (the gap between your flywheel and your coil)

[tarzan13]

tried it today after letting it sit all night with spark removed and air filter off to dry out crank case. and I changed oil ratio to 32.1 like some of my chainsaw body suggested.
and it fired and ran for about 3 to 4 minutes on factory default setting.It idle good.
I had the idle screw wide open.
then it stalled and the same problems started had to clean sprak to make it start .
would only start with trolle half open and cranking like a maniac.
only runs half to full trottle.
i put low needle everyware and nothing.
will have new spark tomorrow hope it works.
the spark color is black and dirty and it should be brown .
another question Im running super unleaded with castor mixing oil and was running 25.1 what are you guys running?
thanks for all your replies, greatly appreciate your help!
ps I did cheque gas cap and every gasket for sign of leaking thighten every bolt on carb.

[VertigoPerformance]

I run 87 octane 40:1 Toro 2 stroke oil
USA uses a different Octane rating than many countries but 87-89 are close.

[Rex]

Try adjusting the high and low needle back to factory Standard.

Accodng to FG's instruktion, that means Turn them all the way in, and then 1 1/4 turn out for the Idle Mixture and 1 turn out for the High-speed needle.
(FG Catalog 3, page 130)


30:1 to 25:1 is fine for Running in. Zenoah recommends 25:1 both for running in and running.

[tarzan13]

Try adjusting the high and low needle back to factory Standard.

Accodng to FG's instruktion, that means Turn them all the way in, and then 1 1/4 turn out for the Idle Mixture and 1 turn out for the High-speed needle.
(FG Catalog 3, page 130)


30:1 to 25:1 is fine for Running in. Zenoah recommends 25:1 both for running in and running.

that weird they say in owner manual idle 1 1/4 turn and high 1 1/2.
well im willing to try any thing.
I live at 1000 feet above sea level can that effect needle adj?

[mradlin]

I find that once the low needle is set at 1 1/4 then you should only need to adjust the larger idle speed screw. That's the way that works best for me. Different altitudes will affect the carb settings a bit, but if you go by the book that's usually a good starting point. Let us know about your progress!

[tarzan13]

Im running big idle screw wide open.
will try new spark and will post result.
thanks guys!

[Budmancan]

Is there any way that you got dirt down the carb? When I snuffed my stock motor it acted the same way and then got progressively worse that it just would not start anymore. Do you have good compression? I find the best way to check without a gauge is to remove the spark plug and press thumb over hole really tight. Pull on rope, your thumb should blow right off the top of the motor. There is alot of compression so it has to blow off, if it just leaks around your thumb then no compression. Hope I make some sense.

[tarzan13]

Is there any way that you got dirt down the carb? When I snuffed my stock motor it acted the same way and then got progressively worse that it just would not start anymore. Do you have good compression? I find the best way to check without a gauge is to remove the spark plug and press thumb over hole really tight. Pull on rope, your thumb should blow right off the top of the motor. There is alot of compression so it has to blow off, if it just leaks around your thumb then no compression. Hope I make some sense.

when I put my thumb and crank it blow off but not extremely high like a millemeter around my thumb is that enough.
Im a big man so maybe i put alot of pressure on my thumb but the air dosent leak it comes strait out like a small fart.Lol
but where i was running was vrey dusty the filter was dirty out side but looked clean from inside.
does anyone knows how much compression pressure those engin should have?
when i crank the engin without holding car down the backend and cranker side lift off the ground like six inch .when i crank slowly i can lift car 3 in on cranker side looks like enough compression to me.
thanks for reply.

[Budmancan]

With my car once the motor went you could tell there was no compression left in the motor. When pulling the pull cord there was no resistance. If you pull it over without the plug in and then put the plug in is it alot harder to pull on the cord. With the thumb trick I do not put all my weight down on my thumb just hold it over the hole? I guess it really does not make sense unless somebody has shown you the difference. I have the compression numbers written doen somewhere will look around to see if I can find them. But somebody told me once(dont know if it is true) that the compression numbers dont mean very much on the smaller motors because of the very small volumes involved. Take it for what it is worth. Will look around for the numbers.

[Budmancan]

Ok read through some stuff. Here are some comments i forgot:
1. The volume in the linkage tube of the tester will throw your reading way off

2. ratio is 9.2:1 or 9.2:1 x 14.95=137.54ft lbs
3. But with a tester people are getting more like 50 - 60 psi on a stock motor.
3. If you put the car on the ground and pull the rope full length with a slow to medium fast pull the left rear tire should come off the ground.

[tarzan13]

Ok an update on the situation.
got new spark and it started with alot of cranking and half trottle.
tried to warm it up and it stalled.
it add 1 trun on hi and 1 1/4 low needle.
it had flooded.
waited and cleared chamber with a lighter.cranked a couple of time upside down clean spark and set the low needle leaner at 7/8 turn.
cranked like manac with half trottle and it started. I warm it up at half trottle with wheels of ground for two minutes and it idled.
ran it for 15 minutes then fine tune it (high needle 1 1/4 low 7/8 to 3/4)
ran it another 5 minutes then let it idle a while then shut her down tried to restart rigth away same problem wont start get flooded.
it gives that little starting sound with the choke and you crank it without choke and trottle and it floodes.
and thanks for the info on compression Bud and it does get the left wheel of the ground.
thank for your help guys!
I`am not new at this been running 1/8 scale for year. I`m the guy at the local track that tunes does .15 to .32 nitro for the newbies went in to 1/5 because it look tought and easy.But these little two strokes are hard.
will get it in time I guess.
thanks again for your help.

[mradlin]

Maybe there's something wrong with the carb. Do you have a spare carb to try on the baja?

[tarzan13]

no spare carb and the new spark plug that had a nice blue and purple spark now gives of a blue and yellow sprak.:(

[mradlin]

Did you check the flywheel to coil gap?

[VertigoPerformance]

How much you want to be it is the plug

[mradlin]

I've had my coil move a bit once. Probably when I hit that damn tree! What do you think would cause it to flood Mlocker?

[tarzan13]

ok i put in spark number 3 it seems to want to start .
so before i burn that one too what is the gap please.
and if the size my blister on my hand are an indication of my devotion to the sport then im a goddam nut case.lol

[mradlin]

ok i put in spark number 3 it seems to want to start .
so before i burn that one too what is the gap please.
and if the size my blister on my hand are an indication of my devotion to the sport then im a goddam nut case.lol
I think we're all a little nutty!! LOL!! If I remember correctly the gap is 0.035 thousanths

[tarzan13]

thats what i got on the gap.
what makes those sprak plug burn?
too much oil in the gas?
ive got some 50:1 in the garage for my chainsaw should i try that?

[tarzan13]

just finish checking magnito gap and its a buisness carte gap.
decided to keep the new spark for testing new gas tommorow.
same super unlead with stilh chainsaw oil instead of castrol, mixture 40:1.
thank for your help.
will post result and if you get any new ideas please tel me thanks again!

[Akela]

to me this is very much now sounding like a problem of getting proper spark. You should not have to give it any throttle to get it started. Try taking the coil off and bringing it in to a local small engine shop, ask if they can test it for you. Most shops will do this for free. Make sure the spark plug wire is making good contact with the plug(the plug is not a loose fit, it should more or less snap on)

[mradlin]

thats what i got on the gap.
what makes those sprak plug burn?
too much oil in the gas?
ive got some 50:1 in the garage for my chainsaw should i try that?
I wish I knew the answer for the plug fouling up. Other than too much oil mix, or the carb being set too rich I don't know. If I think of something else I'll let you know!

[Rock Concepts]

Have you taken the head off yet?

[Akela]

I was going to ask that, but it usally scares people when you ask that.

[Budmancan]

The spark colour should be white spark. Blue is bad. I pulled my plug and have a white spark. Sounds like a coil.

[tarzan13]

to me this is very much now sounding like a problem of getting proper spark. You should not have to give it any throttle to get it started. Try taking the coil off and bringing it in to a local small engine shop, ask if they can test it for you. Most shops will do this for free. Make sure the spark plug wire is making good contact with the plug(the plug is not a loose fit, it should more or less snap on)

Im using ngk sparks.the same kind that was on it .
notice that one side of the coil was closer to magnito then the other so i readjust it.
but the spark from the new plug is a nice blue could it still be no good.
will bring coil to local shop and have it tested.
thanks for info.
was think about removing carb and cleaning it .is it complicated to disaemble.
I did that once with my motorcycle and wound up with a bunch of spring and ball that fell out.ad to go see pro to get back toghter.
look simple on manual ,is there somthing i got to watch for when doing that?
thanks for all your help!
hope Im not asking to much of you guys I just poured alot of money to buy that buggy and I just want to race it so bad!!!
never got to try it on jumps. i just rolled around to breakin engin for 3/4 of a tank that all I got out of it.
thanks again!

[VertigoPerformance]

You don't have to take the carb apart, just remove it and clean it out.
How close is the coil to the fan? should be only a matchbook thickness

[tarzan13]

I haven`t remove head yet because I dont have replacement gasket.
the coil is a buisness card thickness from fan.
matchbook is thicker then card.
is closer better or bad?
what do you clean carb with? regular gas?
does someone as coil gap measurement in thousand of inch?
thank for your reply its realy helping me.

[VertigoPerformance]

I can't recall the thickness in .00"
I use HPI motor spray, about $5.00 a tin and if used sparingly lasts along time.
It is alcohol based so it evaporates very quickly with no residue and no smell.
Closer isn't bad just be sure when you spin your fan that it doesn't hit the coil.
try .02" (2 business cards) I line mine up by eye so I really cant tell but I just measured 2 business cards and it looks close.

[tarzan13]

i`ve got electric motor cleaner and throttle body cleaner.
i think i`ll use the throtle body cleaner.
coil is very close to flywheel but is not touching.
spark color is now white and yellow flash.
buggy too much torn down to try to start but will try after work.
should i make bigger gap between fly wheel and coil?
thanks

[VertigoPerformance]

The larger gap isn't going to make it run, if anything it will stop the flywheel from hitting the coil. The coil distance to my understanding will change the engines power (weak spark, strong spark) it shouldn't cause the problem you are having though.

[tarzan13]

my old sparkplug give a bright yellow spark and its a big flash and the new one with coil adjusted give a whiteflash bearly visible in day light had to close curtain to see it but the old one light up the room.
just giving you guys more info.
if you want good help you need to give lots of info.
thanks!

[VertigoPerformance]

NEW BRUNSWICK!!! Just realized you are from Canada..

[mradlin]

How's the progress Tarzan?

[tarzan13]

went to local small engin mecanic to get coil chequed and he coulnt. said to me that he doesnt know the spec of the coil he need ohms and stuff does anybody know does spec?
I sure the hell dont!
tought these guys should know that.
anyway if sombody could help me out on that one it would be a miracle!

[Budmancan]

According to the Zenoah manual it is the following:
Coil Resistance Prmary: 0.7 ohms Reading taken between primary terminal and iron core
Coil Resistance Secondary:6100 ohms Reading taken between sparking cord end and iron core
Hope this helps.
I belive they have the same coils.

[tarzan13]

found out whats wrong!
first prize goes to Budmancan.
Blown engin!
got wear inside over intake port like someone to 100 grit sand paper and scratch a patch the size of a dime and on exhauste port the size of a quarter!
look like it sucked in dust or dirt . how I dont now but its a pretty ugly sight!
now I need to figuer out if crank is dammaged!
any tell tale signe I should look for?

[mradlin]

Good call Budmancan!! Which engine do you have in your baja Tarzan?

[Budmancan]

When I took apart a good motor it had almost the same marks, but the motor was still good? I was told that these motors rub on the exhaust and intake cutouts causing wear marks?? Hope somebody else can confirm. Can you see crud inside motor? For the price of a complee rebuild kit it is usually not worth while to take the risk and not change out crank.
Dirt can get around the end of the air filter closest to the motor. To solve this use a thin layer of grease to make a better seal, and then use a outerwear over everything to seal it all up. Some people have had good luck with a red neck filter also. But always use a outerwear.

[tarzan13]

I have orignal baja engin in it.
piston and ring looks good and there is no crud inside.
the ware is on top of intake and below exhaust.

[tarzan13]

I just found a grain of sand in base.
thats not good.
how the f**k could sand get in!?
I will put a better filter next time.
thanks guys for all your help!
Now i need to now where to get parts cheap.

[mradlin]

When I blew a engine, these were the two choices I used.
http://www.davesmotors.com/store/product705.html (http://www.davesmotors.com/store/product705.html) This ones a 23cc long block.
http://www.davesmotors.com/store/product1413.html (http://www.davesmotors.com/store/product1413.html) and this ones a 29 cc long block.
If you purchase either one of these all you need to do is take you flywheel, coil, carb, and clutch from the "blown" engine and switch it out. I find this to be the cheapest option in my opinion.
If you choose a headkit, make sure you clean out the lower case really well so there is no dirt or sand in there, so this don't happen again!
Good luck with it! ;)

[tarzan13]

Budman you say that some engin have ware mark but are they deep enough that you could feel them with your finger cause the ware on mine is about paper deep you can realy feel where it ends but the ring and piston look very good only exhaust side of piston is faded in color but you cant feel any ware its only less shinny.
and i thing that the grain of sand fell in while disasembling head because i cant find any other sign of dirt or sand in the base.
Im going to put it back toghter and try it again.

[VertigoPerformance]

If your lower case is still good the 29cc stroker kit for about $90.00 is a smoking deal, I run that kit and the engine is so nice.

What pipe you running? May have gotten dirt in the pipe at one point.

[tarzan13]

thanks mradlin that looks mighty nice.
probaly try it for second engin.
have you ever seen engin ware like budman said?

[tarzan13]

it all orginal out of the box with first tank full.
i removed the silencer like manufacture suggested.

[VertigoPerformance]

That is a good start, now remove the engine and put a bigger one in LOL!!!!!

[mradlin]

I also have seen the wear marks like Budmancan, But if you saw sand in there. It could have worn down things enough to cause some problems. When my engine blew the piston ring was really worn down, causing blowby when it warmed up. There was also a lot of marks and scratches in the cylinder aslo. Good luck with whichever engine or headkit you choose. When ordering a headkit read all of the print to make sure you don't need something like a +2mm stroker crank for example. Because then you also need to order that separate too. If you forget to order that piece you can't put your engine together and have to wait untill that particular part come in.

That's just an example. Whatever you choose, just get it out there and tear up some grass or tracks!!!

[tarzan13]

but the ware would explain the flooding right?

[tarzan13]

has i move along my inspection i notice that the exaust was leaking.
that shouldnt affect anything right?

[tarzan13]

Well its dead found some sand and a grain of metal.
A new engin for me.
Clayton, you talk about putting 29 cc cylinder on 23cc base is that correct?
are o`neil racing engin good?
thanks again for all your help if it werent for you guys i would have gotten back to racing 1/8 scale!

[mradlin]

thanks again for all your help if it werent for you guys i would have gotten back to racing 1/8 scale!
That's what we're all here for! :D

[VertigoPerformance]

Oneills are good and if you are Canadian I think they take care of you since they are displaced Canadians (Canadians living in California) Akela has one of their engines and it is a screamer.

[Budmancan]

No the marks I say were more of a shiny peice of metal. But if you are finding metal shavings in your engine then its no good. I do not know if HPI will warrenty this? Its worth a try. Contact them and send them some pictures of what you found?