Craftsman 358.794963 leaf blower will not start

New to the forum and looking for some help. I have a craftsman 2 cycle leaf blower model # 358.794963 that will not start. It was running a couple of weeks ago and while I was using it the last time it kind of just died out like it ran out of gas. I replaced the plug and a gasket on the carb, as after I took the carb off I noticed one looked like it was blown. Still nothing. The primer ball seems to be working but it appears it is not getting fuel in the cylinder as the plug is dry. I am thinking it is the carb, but just looking for some other opinions before I buy a new carb. Oh, it has spark and will start when put fuel in the cylinder manually, but will not continue to run, just acts like it runs out of fuel.

 

First, inspect for loose fasteners, the ones securing the carburetor and the cylinder to the crankcase.

If the fuel line has a crack or is dry rotted, it will suck air instead of fuel into the carburetor and will not start.

Carbon build up in 2 cycle engines is common and will not let the engine breath. Remove muffler and clean out the carbon. Inspect exhaust port for carbon and remove if needed.

Could be other possibilities but try these first.

 

All fasteners are ok. Very little carbon on exhaust port. I will check fuel line for cracks. If they are cracked I should have a hard time with the primer ball correct? The primer ball is sucking plenty of fuel to the ball, but it is not making it to the cylinder. Also, when I take the carb off and push the primer ball it is pushing plenty of fuel through the carb. I also forgot I found a little clear looking washer that was damaged in the carb, I guess that could be causing a problem. Looks like I am going to have to buy a carb.

 

Just get a kit for it & rebuild the old carb... The kit should come with all the parts you need & the carb manufacturers have excellent manuals to help on there weebsites... Roger

 

Do you know where you can get a kit? I know the carb is available at sears parts direct, but I don't see a rebuild kit.

 

Sears shows the carburetor as Poulan PN 530071775 which converts to Walbro WT-606. Confirm the carburetor is a WT-606; the PN is on the carburetor body.

I would attempt to identify the “little clear looking washer” and where it came from. Was it a metallic disc (welch plug) or a screen (filter). Whatever it is you need to determine what is and where it came from. This is likely the cause of your problem.

Rebuild kits may not contain the part you need. Most small engine shops keep a variety of Walbro parts on hand that are not available in kits or may be just an individual component of a kit.

The links below should help you identify the piece.

WT-606 Carburetor Parts List.
Select a Component*[Frontstep Customer Center*5*Frontstep, Inc.]

WT Series Carburetor Service Manual:
http://wem.walbro.com/distributors/s...s/WTseries.pdf

Diaphragm Carburetor Service Manual:
http://wem.walbro.com/distributors/s...viceManual.pdf

 

Great comments,

When trouble shooting these things most people run to the spark plug.

On 2 cycles not always the issue but in rare cases can be.

On older 2 cycles always replace the gas lines, primmer bulbs, dump gas and start over.

If you have no exprience stay away from removing and diassembly of the carb. Reassembly with no exprience causes and hides the real issue with the machine.

Then check and clean the intake, exhaust, Spark arrester.

If gas is used for preprimer through the carb after all this and it wants to run short periods then it is the Carb and it needs rebuilding and or cleaning.

I have learned that rebuilding with a kit doing it right once for about 10 bucks is the right answer. But once again it takes some know how of the Carb as in needle setting, gasket placement, Welch plug removal, welch plug installation, needle valve settings, Screen removal and installing, pop testing, leak testing and most importantly what to remove and not to try to remove I/E Fixed jets so on. If it is Brass in color Do not touch! These are factory set and will cause you to toss a 30 plus Carb. Also some have a small screw type jet with a very small hole in it. If you dmage this trying to get it out, then it is a done deal. It is soft and will flack off and strip out.

I hope I have helped!

Henry

 

Replaced carb, tried to start, still not getting fuel into combustion chamber, plug is dry as a bone. Just a waste of $30 for the carb. Primer bulb sucks fuel from tank so I doubt it is the line. These 2 cylces pull fuel from vacuum from engine correct? I am used to working on race cars and some 4 cycle small engines that use electric fuel pumps. For some reason it is not getting fuel into the combustion chamber.

 

Make sure you used the right intake gasket if the pulse for the fuel pump goes thru the intake or if it has a seperate line, make sure it's OK & fastened @ both ends..You checked the bolts that hold the cylinder to the crankcase when you checked fasteners in above post?? You do have compression??? Roger

 

If I manually put fuel in the cylinder it will run until it runs itself out of fuel. I have not ran a compression test yet, but I don't think that is the problem.

CRAFTSMAN | Model #358794963 | BLOWER | HOUSING/HANDLE | SearsPartsDirect.com

See above link for parts info. I replaced #1, 2, 5, and now 6. Thanks for all the help, this thing was running great until the day it decided to stop, hopefully I can get it figured out. Where exactly is the fuel pump on this, is it in the carb? Not too familiar with 2 cycle engines so I am kind of learning as I go.


Also, if part #32 is stopped up can that cause t? They list it as fuel tank assembly. I haven't looked at it yet, but it appears to be a filter? If it is a filter I guess I will try that next.

 

Yes, it is a filter and if it is blocked, even partially, it will prevent fuel flow to the carburetor.

 

Thought so....should have checked that first...

 

Yes the fuel pump is in the carb... That's why Airman asked you to check the fuel lines in the second post as it's easier to draw air thru the cracked fuel line than it is to pull fuel from the tank.. Hope it's just a filter,,, Roger

 

I may go ahead and replace the fuel lines as well as the filter as I will have to take all that stuff off anyway. Could it still be the filter even though when I press the primer ball it fills up with fuel? Also, shouldn't primig it put enough fuel in the combustion chamber to make it at least start?

 

How much compression does it have?

Priming the carb doesn't put any fuel into the cylinder, so no.