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I got a Craftsman leaf blower 79160 from an auction, it was new as far as the packaging was bit damaged. I followed proper instructions with the exception of maybe a clean yet older fuel. Used proper 40:1 2 cycle oil and it started just fine after a few tries.

In the beginning the throttle did take a while to break in, but eventually it ran great. About 30 minutes after using it, it shot bit of white smoke and stopped running.

I've checked spark and it sparks, drained and provided it with fresh oil+gas mixture. It still will not start.

Please advise on what to do

https://www.sears.com/craftsman-25cc...-07179160000P8

Did you tune carb screws any?
Is rope easier to pull now - compared to before 30 min run time?
Pull rope 10x. Pull plug - is it wet or dry?
Put tsp of fuel in plug hole. Re-install plug. Pull rope 15-20x. Should get a burp and 2 sec run IF: Good Compression & Good Spark at the Proper Time.

Hate to say it but these two strokes are about the cheapest piece of crap around. One main bearing, no real crankshaft, stamped steel rod, pot metal head, and so on. That puff of smoke is a real bad sign when the ignition is still good. Keep us posted on your findings.

Thanks for the tips folks.

Being it was new I didn't do much to it yet besides refresh tank of gas/oil mix. I did read reviews after for this 2 cycle blower and it was pretty horrid.

I will test the method you recommended soon as I free up. Dougand3

The only thing that I'm pondering over is when I unscrewed the choke part out to see the carb. There was a single small black washer that I wasn't sure where it was originally located. I put it where I think it should be, but were not able to find any diagram to confirm for sure where it should be.

tom3 said:

Hate to say it but these two strokes are about the cheapest piece of crap around. One main bearing, no real crankshaft, stamped steel rod, pot metal head, and so on. That puff of smoke is a real bad sign when the ignition is still good. Keep us posted on your findings.

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I happen to run into a local Ace hardware and noticed their store does small engine repairs, decided to just have a chat with them. Was recommended to purchase a pre-mixed Oil+Gas 40:1 that supposedly does not contain alcohol/ethanol. Even though the cap of the leafblower cap says 10% ethanol. I decided to try anyways. To my surprise on a very cold day it I emptied the tank and replaced it with the new oil/gas can. It started up right away for literally 1 second and died.

Few days later on a warmer day, I tried again and it started up just like it did originally. Runs, throttle control as it did before is rather Rev high, or too low where it dies. After running it for 5 minutes it died again. Then struggled to start up again.

I'm starting with agree with you that not just 2-cycle engine is the crappiest, but especially this model had terrible reviews on starting issues.

Not sure what to do now :thumbdown:

Another thing to look at. Get a piece of wire, bend a hook on it. Get into the gas tank and pull out the supply tube. Look for a crack in the line or a dirty filter. Maybe pull the filter off and blow through it.

tom3 said:

Another thing to look at. Get a piece of wire, bend a hook on it. Get into the gas tank and pull out the supply tube. Look for a crack in the line or a dirty filter. Maybe pull the filter off and blow through it.

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Okay cool, I'll give that a shot. Soon I may have to give up, sell it cheaply and buy a better one. Maybe even 4 cycle or battery powered ones Lol

When you have a problem like this you need to start by working out if it is fuel or ignition related.
This is done by spraying a very small shot of carb cleaned down the plug hole & give it a dozen pulls with a wide open throttle.
If it fires then the timing & ignition is OK.

If the engine fires then time to look at the fuel supply.
If the unit has a supply & return line to the carb then the entire fuel system runs at around 5 to 10 psi
So the next thing to do is pressure test it.
Starting with the tank which should hold about 10 psi and so 0 resistance to vacuum
Then the carb needs to be pressure tested the supply line should hold 10 psi of pressure and not leak down under vacuum
Then the return line which should again hold 10 psi of pressure and show 0 resistance to vacuum .
I like to pressureize the tank and watch the flow of fuel out of the supply line.
If it has a felt filter then very small amount of water can effectively block the filter.

My personal "best guess" is there is something holding the needle off the seat.

some people buy a product, take a part off for their own device then put the part off theirs back on and return it. Looks new but the part that was replaced can be used. It is unethical as heck to do that but I hear people brag about it all the time. The problem you are describing sounds like the fuel pump diaphragm flap on a lot of small carbs. When it doesn't seal the engine doesn't bet a steady supply of fuel. The solution is usually to replace the carb with a new one because they are about the same price as a carb kit. I think the last carb I rebuilt cost me $10 plus $3 shipping for a carb kit and $14 free shipping for a new carb. Anyway, I think I would put a new carb on it and see if that cures it.

Running then dying, sometimes is the ignition module going out, but hasn't completely gone bad.

PTmowerMech said:

Running then dying, sometimes is the ignition module going out, but hasn't completely gone bad.

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Nothing like trying to diagnose a failed ignition module that never looses spark. Mostly related to the spark advance type modules with the internal revolution limiter. Those things can give some strange symptoms.