dan rox 90

Hi I have a hpi baja and yesterday I was running the car and I ran it empty I've just bought this baja from a guy and he said it was one year old but it's in good condition and I was running it yesterday and now for some reason it dosnt want to start, could it be a bad spark plug? Could I have flooded the engine I did flip the baja over and pull the pull start to unflood it but nothing much came out.
cheers help much appreciated

phmaximus

Could be......do u have much experiance with starting 2stroke engines?? We're u doing the cold start method?
Does it have a kill switch?

first things to check... Air, fuel spark.

does it have spark??
if fuel making it up into the fuel bowl??
is the air filter clean??, make sure the hole in the fuel cap is not blocked

dan rox 90

Yer the air filter is clean and the spark has a spark because I tested it on the engine. What is the cold start method.
cheers

phmaximus

Cold start.... Prime fuel bowl, full choke, pull cord till it "pops". Turn of choke and pull... It should start away,
pops=starts and runs for 1 second

ok, so it has spark, is it a good bright spark??

next.
take the fuel cap of the tank, u will see a little hole in it... This allows air to enter the tank as the fuel exits....
Can u check the hole?? Can u blow though it??

next... With all that checked Does the motor pop???
and ur using fresh 2 petrol/oil and the motor has good compression??
is it a genuwine HPI Baja or a clone?

dan rox 90

Nah it's a genuine hpi baja yer I have a feeling it has something to do with the spark plug or carb. It has good compression I'll try a new spark plug them I'll check the fuel cap.
thanks for the help!

LORD SHADO

I use camp fuel from walmart no smell

cbaker65

It could be an air leak in the fueline or primer bulb is cracked.Also,make sure the fuel filter didnt get stuck at the
top of the tank.
To check the gas cap,its quite simple,just loosen it up,or remove,an then try to start,if it fires an run,then the breather
is bad on the cap.
To check in general with sparkplug or lack of fuel,pull sparkplug,put alittle gas in cylinder head,put spark
plug back on,then crank it over,if it fires up,then your good.
Worst scenerio,bad diaphram,or technicly,the fuel pump.Usually the engines start on choke mode,but
will die asoon as you take choke off...

nitrosportsandrunner

take the spark plug out, put a few drops of fuel right into the engine and try to start it.
If it starts and runs for a bit and then dies, you at least know you have both spark and compression.
If you ran it dry, the primer bulb on the carb should be enough to get fuel to the carb...unless the bulb is cracked or there is some small air leak in the carb or between the carb and tank. sometimes if an engine is hard to prime, putting fuel in the spark plug hole and making the motor run on that for a few seconds is enough for the engine's suction to pull fuel through the lines and into the carb.

phmaximus

If u are worried about the spark plug just do a visual inspection. There are a few videos on YouTube that will help learning what to look for.
but generally they are very resistnt.

so yeah, report back when u have checked the fuel cap, and like the other guys sugested try manually adding fuel to see if it will at least pop...

if u can get it to pop by putting feel down the spark plug hole but it won't anyother time it's safe to say its a fuel system related problem...
if that's the case... You need to work out if the problem is in the tank/lines or the carby.
If it's priming properly and still not starting with the cap removed it's generally safe to say it's no the tank

so that leaves the carby..... As far as carbys go they are very basic and there are a few how to rebuild videos and threads. Either way it might be worth fleshing it up anyway just to get that bit of experiance

dan rox 90

Hey guys I tried to start is without the cap and it didn't start then I put 8 drops of fuel in the engine and it still dosn't want to fire up. I'm really confused on what to do next. Should I take to carb off?
cheers, thanks for the help guys.

LORD SHADO

The gap of the generator and fly wheel you need to check . If no spark on plug

phmaximus

I wouldent take it off just yet.....
Did u put the fuel down the spark plug hole, refit the spark plug and turn the choke off before trying to start?

also does it have a electronic kill switch and are you 100% sure that it has a good spark not a weak spark?
test the spark againe and try more fuel down the hole

phmaximus

Here I've got an idea...

If u are sure it has spark and it's good, maybe replace the plug anyway... But get yourself a can of this....

http://www.supercheapauto.com.au/onl...a-*******-350g

dan rox 90

A can of what? ( the hyperlink didn't come through), and tomorrow my new spark plug will come and I will I form you on what happens when it comes.
thanks for the help much appreciated.
cheers

phmaximus

Go to supercheap and get a can of.....



Or or a cheaper option, but less funny



And if that does not work with a new plug report back

cbaker65

You can also pull the plug,put plug wire back on,hold the spark plug against the head,then pull starter to check spark.
You should see spark,if not,it could be bad plug,bad coil,or bad kill switch that is shorting out.

Check switch by removing it,un hook the wire,an try starting it with out it...

phmaximus

I think he tries that..... 3 post.

dan rox 90

Hey guys so today I got my new spark plug and I put it in and my baja still didn't want to start. I sprayed Somme of the start ya bustard spray in the carb but still didn't work. Should I take the carb off and have a look at it. There is spark coming from the new plug I try a few drop of fuel in the piston but it didn't work. What now?
thanks

dan rox 90

I started it using this method


Remove plug
Whip engine over about 12 times very fast
Place 3-4 drops of straight 2 stroke oil down the plug hole
Turn engine over very slowly 4-5 times
Put a known good plug in
Choke off, throttle wide open and pull to start.
May take alot of pulls but it will go.
Once fired hold throttle open to clear out excess oil from the engine.
thanks for your help guys.



so was running it and it was running rather slow I just bought this car a few weeks ago and I noticed that it was running slow from when I first had it. Could there be any reason whys it's running slow?

dan rox 90

The accelerations good but the top end ain't so good..

phmaximus

Yay.... It starts.... Now u need to tune it....

i dont know if no if I recemend this but... I tuned my 5ive like a chainsaw.....and it worked very well

get it on a bench with the wheels off the ground, start her up and get it to normal running temp. Never tune a cold engine.... Then get someone to hold full throttle while u adjust the HSN. U want to adjust the HSN so u are getting maximum rpm from the motor... And when doing it try to set it as quick as possible so u are not holding the engine on readline for long periods of time

dan rox 90

Ok thanks I'll give that a try

Gavman316

Hi guys . I have a HSP BJ5S BAJA . and it's on a week old . I've followed the book in running it in . I've had it take off on me and smash into my own car while out with the Baja . And brake the front lower suspension arm and steering mount . I fixed then . Sweet took it out today running just half throttle and it's stops . And I can get it to fire . It's got gas it's got spark . I installed a kill switch fail safe that cut the engine off as well as applying the brakes . I've unplugged it to see it was the cause and no difference. I've done all I can think of to see if it's the problem. Could it be a poor spark even though it has spark and not sparking how it should . Eney ideas guys . I have a new spark plug on the way . But I've tried all I can read to try or think to try but a new spark plug ... Help me please .. it's bull at this stage as the car is only a week old ... Gavman