I was on here a month ago and explained my issue with my blaster. Its bored .40 over and everything else is stock. When i start it, i hit the gas and it boggs for a second then races up real high for about 5 to 10 seconds depending on how hard i tapped the gas. Then once that gas burns up finally it will gradually come down and die unless i hit the gas again and it repeats itself. People on here told me to do a leakdown test and change the stock jets to a 360 main jet and a #35 pilot jet. Same problem. i tried changing the needle and no difference. Please someone tell me what this is cause im ripping my hair out trying to figure this stupid problem out. Thanks Bill
my blaster still revs out of control
- Thread starter bdubbs82
- Start date
Not a leakdown test but i did a compression test and its 125. I had a guy inspect it for leakage but not sure what he did exactly. He just said it wasnt leaking. do u think that a leak could be making it rev up and stick by itself? And for the jetting it didnt seem like it made a difference whether it was the 360 or the stock. But ill get a 260 anyway its worth a try.
not sure where you got a 360 jets. I myslelf didnt know they went that high. but maybe they do.
I don't know what that person looked at or did to confirm its not leaking.
a compression test, does not confirm it does not have a air leak. most air leaks seem to happen in the cases. gaskets to bad crank seals.
I would reocmmend that you follow up and see how they did a leak down test ? what the tool looked like and how it was hooked up.
There are a few things else it could be, but i think until a proper leak down test is done. you might be just passing by what it most important to do now.
If you keep at it, trying to start and run it. you likely will lock it up or blow it up and cause real costly damage to the motor.
However, I will mention some other things 4 you.
replace the spark plug.
cuse cable lube, clean your cables, make sure the throttle cable is not shot or worn out.
confirm the reeds are good and not worn out or damaged.
If you running oil injection and not the block off kit.
clean the tors and slilder
Lower the main jet to a lower number, if indeed you found a 360 and had it installed. to a 260 or 270.
A compression test is not a test, that checks the lower pressure of the crank case. See that pressure, no air leak.
A blaster is a vacuum fed engine. the 2 cycle engine, the ports and wholes in the piston, lower, the post wholes in the piston and cylinder match up in cycle, suck in the gas and oil. puts it into the top of the cylinder, and ect.
A lower end crank case, air leak. would not provide the proper suction of the air flow to pull in the gas and oil.
And if you do fail a proper leak down test, it might not just be the seals, it could be a crack or broken inner case ! or a bad seal with the two case halves.
Sporty
I don't know what that person looked at or did to confirm its not leaking.
a compression test, does not confirm it does not have a air leak. most air leaks seem to happen in the cases. gaskets to bad crank seals.
I would reocmmend that you follow up and see how they did a leak down test ? what the tool looked like and how it was hooked up.
There are a few things else it could be, but i think until a proper leak down test is done. you might be just passing by what it most important to do now.
If you keep at it, trying to start and run it. you likely will lock it up or blow it up and cause real costly damage to the motor.
However, I will mention some other things 4 you.
replace the spark plug.
cuse cable lube, clean your cables, make sure the throttle cable is not shot or worn out.
confirm the reeds are good and not worn out or damaged.
If you running oil injection and not the block off kit.
clean the tors and slilder
Lower the main jet to a lower number, if indeed you found a 360 and had it installed. to a 260 or 270.
A compression test is not a test, that checks the lower pressure of the crank case. See that pressure, no air leak.
A blaster is a vacuum fed engine. the 2 cycle engine, the ports and wholes in the piston, lower, the post wholes in the piston and cylinder match up in cycle, suck in the gas and oil. puts it into the top of the cylinder, and ect.
A lower end crank case, air leak. would not provide the proper suction of the air flow to pull in the gas and oil.
And if you do fail a proper leak down test, it might not just be the seals, it could be a crack or broken inner case ! or a bad seal with the two case halves.
Sporty
Depending on elevation and tempature, every thing stock needs a #230 main, 32.5 pilot and stock needle on middle clip.
If you run 32:1 premix add one size main.
Here you are try this as advised earlier.
If it passes the test with no leaks proceed with setting the idle.
Idle adjusting.
Start with air screw 1.5 turns out.
Set idle screw so that it has some sort of idle.
Warm up motor and then set idle screw for a fast idle.
Adjust air screw either way to get the fastest idle.
Adjust air screw a little at a time leaving 10 secs to allow the motor to respond.
Re adjust idle screw for desired idle .
I would bet a dime to a pinch of poop that the problem is an air leak.
If you run 32:1 premix add one size main.
Here you are try this as advised earlier.
If it passes the test with no leaks proceed with setting the idle.
Idle adjusting.
Start with air screw 1.5 turns out.
Set idle screw so that it has some sort of idle.
Warm up motor and then set idle screw for a fast idle.
Adjust air screw either way to get the fastest idle.
Adjust air screw a little at a time leaving 10 secs to allow the motor to respond.
Re adjust idle screw for desired idle .
I would bet a dime to a pinch of poop that the problem is an air leak.
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