So I picked up a basket case husqvarna 345 for $20 to use as a beginner learning experience. Put on a cheap 350 jug kit (yes china) and new carb. Fuel line shows fuel, plug has spark, but she won't fire up. Adjusted carb to factory workshop numbers. Impulse line appears ok, not pinched. There was one pull where it sounded like it wanted to go when I first tried firing up but nothing since. Where do I go next? Dare I say the dreaded air leak?
345 rebuild, spark but no fire????
- Thread starter JNap
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MechanicMatt
Cut Split Stack Burn
Compression and what did you use to seal the bottom end up with?
nmurph
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Did you try dibbling a little mix down the carb throat? A tablespoon or so, point the saw downward, pull the throttle, and slowly pull the starter over a couple of times. Then, pull it to see if it pops.
You don't know why the saw failed the first time? The bearings and seals in this saw are one-piece. If there is a leak around the seal, you have to replace the bearing at a cost of about $20/ea.
You don't know why the saw failed the first time? The bearings and seals in this saw are one-piece. If there is a leak around the seal, you have to replace the bearing at a cost of about $20/ea.
MechanicMatt
Cut Split Stack Burn
Is the plug wet?
Didn't check compression yet, can't find my gauge.... Sealed bottom with hondabond, if your not familiar it's great gasket material resistant to oil and gas. Used supplied gasket in between spacer and jug.
I did try dumping a little fuel (fresh) and still not go. It appears to have had straight fuel failure. New bearings and seals installed.
Not as wet as I would have thought it would be from pulling it 100 times. Even with dumping a little fuel right in there.
MechanicMatt
Cut Split Stack Burn
Screen on the muffler plugged?
Is the spark blue?
What did you use to set the gap on the coil?
Did the flywheel "jump" timing? It could be firing but not at TDC............
Is the plug fouled?
Hondabond is good stuff, I use the GM anerobic sealer only because I work at a GM dealership and get tons of it for free.
Good Luck, and don't give up. When you figure it out, all the work helps build up a great feeling of reward. Love that instance when a engine comes alive for the first time
Is the spark blue?
What did you use to set the gap on the coil?
Did the flywheel "jump" timing? It could be firing but not at TDC............
Is the plug fouled?
Hondabond is good stuff, I use the GM anerobic sealer only because I work at a GM dealership and get tons of it for free.
Good Luck, and don't give up. When you figure it out, all the work helps build up a great feeling of reward. Love that instance when a engine comes alive for the first time
Screen on the muffler plugged?
Is the spark blue?
What did you use to set the gap on the coil?
Did the flywheel "jump" timing? It could be firing but not at TDC............
Is the plug fouled?
Hondabond is good stuff, I use the GM anerobic sealer only because I work at a GM dealership and get tons of it for free.
Good Luck, and don't give up. When you figure it out, all the work helps build up a great feeling of reward. Love that instance when a engine comes alive for the first time
Spark blue, brand new plug not fouled, gap set with .305mm gauge. Magnet on flywheel appears to hit coil at TEC.
Gap set
A plug gap at .305mm may be too narrow to fire, open it up to 0.020" or .025", which is .5 to .6 mm
A plug gap at .305mm may be too narrow to fire, open it up to 0.020" or .025", which is .5 to .6 mm
Since you used a cheap chinese p&c I think I would check compression, also are you sure the flywheel is set correctly? If it won't pop when fed straight fuel and it's not flooded it has to be compression or spark....
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That was his air gap on his ignition....I think.
OK, my bad...the information kind of runs together as presented.
Yes I was referring to the coil gap when I said gap set at .305mm.
I checked compression tonight and after 3 pulls she was at 90, however, the threaded section of my tester was too long to be fully threaded to the shoulder and o ring seal. I had to make due with Teflon tape and partially run it in so I'm not convinced the reading was accurate. I'll have to find another tester to use.
How would I check flywheel? What exactly am I looking for? Like I said before, it has spark but maybe not at the right time??
MechanicMatt
Cut Split Stack Burn
When you were pulling the rope did you hear any hissing coming past the teflon taped threads? Id get the appropriate gauge. Id pull the flywheel and check the key way just to rule out the ignition timing. Next try a little more fuel. Remember, AIR FUEL SPARK. In our case AIR translates to compression. Good Luck
When you were pulling the rope did you hear any hissing coming past the teflon taped threads? Id get the appropriate gauge. Id pull the flywheel and check the key way just to rule out the ignition timing. Next try a little more fuel. Remember, AIR FUEL SPARK. In our case AIR translates to compression. Good Luck
Like Matt said, pull the flywheel and verify the key way is lined up. The key way can shear and change the timing.
Oh man, I missed the part where you said it appeared to pop once. Pull the spark plug and leave the saw upside down over night to make sure it wasn't flooded. When you try to start it again try cranking on fast idle without setting the choke.
What is my starting setting on the idle speed screw?
john_bud
ArboristSite Operative
If it's really at 90 psi with a new p/c, it has some issue. Is the ring installed upside down? Leak around the gasket? When I redid my husky 51, the cyl gasket was missing a hole for (i think) the impulse. Anyway, it wouldn't run till I duplicated the factory gasket.
