20 Most Recent Husqvarna Chain Saw Models 51, 55 Questions & Answers

Check flywheel key again, I've seen ones that were partially sheared, would not start. New key and they start right up

Larry,Carburetor may be dirty, remove and clean or rebuild. Check the attached links,videos,instruction and guides, Good luck "I hope this helped you out, if so let me know by pressing the helpful button. Check out some of my other posts if you need more tips and info." Husqvarna Chainsaw 235Troubleshooting Repair Help How to Troubleshoot Husqvarna Chainsaw Problems eHow Husqvarna 136 Chainsaw Carburetor Rebuild Fuel Line Repair http://www.mymowerparts.com/pdf/Husqvarna-Service-Repair-Manuals/W9200002.pdf

Several bar and chain combinations fit the 51 model saw. If your saw runs an H46 / H80 or H81 style chain you will need a 7/32" (5.5 mm) If you are running a H21 style chain you will need 3/16" (4.8mm)

check fuel lines are not damaged check carb diaphrams and inlet needle

Check to make sure the brake binder is not engaged...which is the same as saying: check and make sure the kickback brake handle is fully cocked. The handle should be oriented rearward towards the forward hand grip. If it is forward, pull it back stongly until it lockes in place. (Hint: also make sure the binder is released/brake cocked always before attempting to remove the brake assembly from the saw drive engine subassembly.)

Make sure you are using a resistor plug. This is extremely important on this model. If this is not the issue, remove coil, use emory cloth to clean the mounting area for the coil. Trash or oxidation can prevent a good ground on the coil. Lastly make sure the air gap (distance from flywheel to coil is correct) itshould be .012"

If spark is ok then I would say the carburetor is the likely problem or the fuel is not entering the engine. Something like the following instructions might help. How to Adjust Husqvarna Carburetor eHow Look at this manual for model 51 carburetor adjustments. http://www.getsaws.com/PDFs/w9600001.pdf

These saws were normally ran on a slightly richer mix. The reason was becuase of the mix oil available. I would recommend running a 40:1 or 50:1 mix. Make sure you use an "FD" rated mix oil and Premium ethanol free fuel. The premixed fuels / oils are even better. They contain the FD rated oil 95 octane fuel and no ethanol.

Here is the manual for the 51 saw. The sprocket should not wobble and I think you are on the right track, probably should replace it! http://www.manualslib.com/products/Husqvarna-51-240393.html Hope this helps ! Cheers!

Here is a link for the throttle link manual diagram and instructions. http://www.manualslib.com/manual/74034/Husqvarna-340.html?page=17#manual good luck!

Sounds like you have a stretched chain if it has not been replaced

dont know off the top of my head however you can get a thread identifier tool for 5 bucks, or if you have a tap and die set you can see which one fits then read the number off the side

You should check the carburetor to see if you don't have any vacuum leaks or gas leaks. You may have to replace the gasket under the carb. Before doing that , check to see if your choke is working right.Also check the filter and hose inside the gas tank to see if they are good. The filter unclogged and the hose not leaking. If it is none of the above, the carb probably gave out. You may need a new one.

Most saws have a compression release valve which you press for that reason. It is located on the cylinder at the back of the saw. I don't know if the 55 has one , but it should.

You can do that. But it would not run as good or as long as it would buying both the piston and the cylinder housing. You either have to buy both or the try installing a new piston with new rings in it. It should give you enough compression to start it up. But it can't be guaranteed to last too long.

The 55 spring is supplied in a black plastic keeper, its just a matter of removing the centre screw, remove the pulley, the spring is then captive in the keeper, carfully ease out ( always wear saftey glasses ) you can now drop the new spring in.

Check piston rings. Sounds like you have a seized engine.

In my experience you can do all the testing you like, but if the coil does not perform properly on the machine then it requires replacment