# help husqavarna 61 trouble



## tomatick (May 5, 2011)

OK had good running husqavarna 61, Oil pump when out.
When attempting to take off clutch to get to oil pump broke crank shaft (Left handed thread). Replaced crank shaft replaced oil pump. Put saw back together replaced gaskets. Now saw will not start, barely run for 10 seconds if gas put in cyclider and shut off....
Tried the following
Getting spark
Put fuel in cyclinder saw run 10 seconds
adjust carb to factory setting

What could be wrong? Could I have a air leak?

Please help


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## paulr44 (Oct 14, 2008)

It ran before you repaired it. What changed? Most likely a crank seal lip got damaged or inverted during assembly. Could have something incorrectly assembled in the intake area, causing the fuel pump not to function. Could also have a fuel line pinched or something you'd not expect. Unless you have the equipment to perform a crankcase pressure/vacuum test, you're going to have to poke around.

I'd lean toward a vacuum leak, like I said by a crank seal. There are too many unknowns for anyone to give you an exact diagnosis.
Paul


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## tomatick (May 5, 2011)

Paul, 

Thanks for your help, I so not know what changed. Nothing as far as I know. I will check crank seals. I did not mess with intake area. How does fuel pump work? Getting fuel to the carb, so do not think fuel line is pinched. I think I have crankcase pressue. How is vacuum test done.

OK ready to poke where should I start. Getting very fustrated


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## tomatick (May 5, 2011)

More information, only runs for 10 seconds when throttle is on half way or start. Will not run at zero throttle or choked. Only when throttle is on half and will only run for 10 seconds. Then need to put more full in cyclinder.


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## paulr44 (Oct 14, 2008)

I asked "what changed," to cause you to think. It worked before, so what changed is whatever you did, on purpose or by accident. If when you replaced the crank, if the seals on the crank were in place when you assembled the crankcase (CC), then most likely they're okay. But you have to review that in your mind if your a novice. You have to pay attention when putting seals on cranks, as the lip, of what's called a lip or garter seal likes to roll inverted. When this happens, the seal is rendered useless.

Husky likes to route a fuel line from the tank up through a grommet to the airbox where the carb. is. If it got pulled out some from the tank, the slack could have kinked, causting the problem you're experiencing.

If the cylinder gasket was re-used, or the new one went askew and isn't sealing, the problem you have would be explained.

Bottom line is, it ran before so you're missing something they you inadvertently changed, or something you inadvertently mis-assembled.

Review the steps you took in your head, perhaps you'll figure it out. Else you're going to have to perform a CC pressure/vacuum test or review the fuel system.
Paul


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## tomatick (May 5, 2011)

Paul, thanks again. I know it worked and now does not. This is the frustrating part. Yes something changed. I do not know what. I ordered new crank seal. I will change these and go from there. Getting fuel to the carb. Getting spark. Right now I am assuming a vaccum leak through the crank seals. After changing seals will report. If not this then will look to carb. No carb adjustment were made.

What else can I check and in which order should I check?


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## paulr44 (Oct 14, 2008)

ASSUMING that the compression is good, the intake side of the piston skirt is good, and that the saw ran well before...
(AND assuming if so equipped, the compression release is pops out and seals when the saw does start)

It's hard to say, but I'd start with the fuel system.

Test 1 - see if the carburetor is getting, and can administer fuel:
A simple test, requiring in reality, no special tools.
You need to have access to the carburetor main metering cover, assuming it's a WT type or similar carburetor. THIS cover, on Walbro's has 4 screws, while the pump side usually has one big screw. YOU MAY need to remove the carb. to gain access to the cover, and hole in it's center.
The fuel must be reasonably fresh.
You need either compressed air, and an blow gun with a tease throttle (one that the more you squeeze, the more comes out), or a dull probe such as a bobby pin.
SHAKE the saw some to stir up the fuel, creating additional vapor pressure.
If using blow gun, blow a little pressure at (NOT WITH GUN ON HOLE).
If using probe, press lightly into the center of the hole against the diaphragm tab.
Fuel should flow out of the venturi of the carb. and continue for awhile as long as you're blowing/pressing the diaphragm.
If so, the carb. should be good to go. If not, kinked line or restriction somewhere.

Test 2 - test for vacuum leaks.
THE ONLY way you can do this test, is to have the saw running, even if on near full choke. If it won't do that, you can't test it without a pressure/vacuum tester.
Run the saw. BEING MINDFUL of a hot muffler and the fire hazard, and wearing safety glasses, spray a little carb. cleaner around the intake manifold, LOOKING FOR A CHANGE IN RPM. *IF* you hit the THROTTLE SHAFT AREA of the carb., it will draw it in and change RPM. Spray around the cylinder base gasket to test that area.
TO TEST the crank seals, it's almost impossible to test the clutch side on most saws. To test the flywheel side, on Husky's you should be able to run the saw without the top cover, and spray behind the flywheel. AGAIN, please be careful. THIS IS WHERE you'll need the goggles!!

If you're going to be doing repairs on 2-strokes, you should invest in a pressure/vacuum tester, such as a MityVac.
http://www.mityvac.com/pages/products_hvpo.asp
http://www.harborfreight.com/catalo...m_term=mityvac&utm_campaign=SubBrands - Exact

In order to use the tester, you'll need to block off the exhaust port, and intake. STIHL sells nice wedges of rubber REAL CHEAP, or you can use pieces of an old inner tube. I have made my own plate from 3/16" or 1/4" scrap plate metal for special intake systems. but you can often use the carburetor as a plate. IF THERE'S A NIPPLE from the carburetor to the rubber intake manifold, you'll either need to make a plate, or improvise. Turn the carb. around, and use a golf tee in the hole in the man. for the nipple. Things like that. UNLESS you make your own plates, or buy some (Stihl sell them for their units, can't speak for other brands), YOU'LL NEED to get a compression tester fitting for the spark plug, and adapt it to the tester.

With the intake and exhaust blocked off, you apply pressure (via the spark plug boss or an intake plate) and pump it up to 7.5 to 8 PSI, or about 0.5 to 0.53 Bar (atmostphere). It shouldn't lose more than 1 PSI (.6 Bar) in 20 seconds. Vacuum test should be the same way, but the pressure test is more important.

NOTE: If you make you own block-off plates such as I've done, for either exhaust or intake you can drill a hole in the plate, tap it with a pipe tap and screw a fuel fitting into the hole to use as a hose connection for your tester. Cheaper and easier than fanagling a compression tester fitting for the plug boss.

IF YOU lose pressure beyond what I mention, spray soapy water around the intake, exhaust, spark plug too, cyl. base gasket, and of course those crank seals. And although very rare, the crankcase gasket too. Any bubbles are of course, pointing out a leak.

To have any gas engine run, you need spark, at the right time, good compression, and a fuel-air mixture. 2-strokes being what they are, have this giant intake manifold, called the crankcase. Any leaks in it can cause problems, with symptoms such as your saw has. Of course, other reasons can mimic a CC leak.

Paul


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## tomatick (May 5, 2011)

Paul,

Thanks, I am waiting for the crank seals. Will replace and go from there. Hopefully, this will be the problem. Any advise on how to change without creating more problems.

Saw does not have compression release. My 257 and 372 do have the compressoion release.

As said previously saw run strong before.


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## paulr44 (Oct 14, 2008)

Only advice is to be careful and ensure the lip (the inside edge) doesn't roll over and invert. A thin layer of red RTV on the perimeter of the seal isn't a bad idea either, but not mandatory.
Paul


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## tomatick (May 5, 2011)

Paul,

Ok changed crank seals. One was a little worn. Saw seem harder to pull (More compression). Saw still will not start. Ocasionally, will run a couple of seconds with throttle half open. A couple of things, saw will run a couple of seconds then bogg out. On the next pull seems to back fire. Ten more pulls will run for a couple of seconds then bogg out. Then back fire. . Will not start when choked, or throttle at zero for full. Tried to adjust high and low carb screws. No change. Could the timing be off? When changed crank shaft from parts saw flywheel side of crank shaft was bigger diameter so used flywheel from parts saw. How is timing set? Flywheel is keyed. Flywheels are same diameter on the outside.

What else could be the problem. Getting very fustrated. I think I have good compression, vaccum, spark, fuel. Please do not tell me carb. 

Thanks again

Todd


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## paulr44 (Oct 14, 2008)

From my previous post: "I asked "what changed," to cause you to think. It worked before, so what changed is whatever you did, on purpose or by accident."

Flywheels can change on same model units when they change ignition coil types. Or when they go from a breaker points set-up to a solid state set-up. You mention you used a flywheel from a "parts saw." Is it identical? The flywheel key orients the magnets and thus the ignition timing. If the flywheels aren't identical, then likely that's the problem.

Again, what changed is the best diagnostic tool I can suggest since it ran before....
Paul


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## tomatick (May 5, 2011)

Paul,

Thanks, The fly will was in the incorrect place. Moved and started on first pull. Runs strong, now happy.

I got so focused on crank change total forgot about flywheel change. I can verify the key slots on the cranks are different. I should have picked up on this.......

Thanks again saw runs as before.... 

The husky is a welcome return, had to use an old eager beaver in the mean time.


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