# HS 521 dies out after it starts up



## Biketrax (Jan 28, 2015)

Cleaned carburetor 3 months ago, no new parts. It ran well then.
I did not use it at all, over the winter. Starts right up, Runs about 5 min.
Then after it sits for awhile 20 plus min. it starts right up again. However after running a few minutes and it warms up it does not start up again. I am not that familiar with this unit it was given to me. It ran well no issues for years from previous owner.
Gas is Fresh! Plug has good spark( could it be faulty?)
The few things of issue for more information:
1) when I stand it on end gas trickles out of the cap, it does have a (loose) gasket so is it an air issue? I have loosened the cap while running no change.
2) When I first put it together few months back, a little oil was coming out from under the governor arm lever. (When checking oil seems there is excess pressure with the oil, the oil level seems right on) I cant really tell if I still have this issue? 
Whats the next step??
Start over again with cleaning and replacing new parts in the carburetor.


----------



## bwdbrn1 (Nov 24, 2010)

It's not unusual for gas to leak out when you stand the machine up on end. Nothing to worry about there. I believe there is a filter inside the gas tank on those. You might want to remove the tank and drain everything out of it and check to make sure debris hasn't clogged it up.

I'd try cleaning the carb again, maked sure the sediment bowl is clean, and install all new gaskets between the engine and carb.

Take a look at the video here. It's from Honda Europe, and it shows how to best clean the GX160 carb.

Service movies - Honda Engines

They show applying heat to remove the cap from the pilot screw. I don't think you can do that with the U.S. ones anymore. I believe you have to break the cap off, and replace the pilot screw with a new one.

This chart shows the innards of that carb.

http://honda-engines-eu.com/documents/10912/31055/1483/e9844030-8016-4d4a-8d30-d1e8cd215253


----------



## Hap (Mar 15, 2015)

If you go back to the carburator you may want to consider just buying a new one. I bought a used HS520 that was surging and backfiring and rather than cleaning the old one out since it was an older machine, I opted for just replacing it. They are fairly cheap on ebay, about 35-40 bucks, and another 10 for the gaskets. I did remove the fuel filter and replace with new one as well which was located inside the fuel line where the line is attached to the tank. It was very dirty and there was debris in the tank as well. After putting it back together (hardest thing is to line up the gaskets and spacers with governor attached) the HS520 ran and choked perfectly.


----------



## [email protected] (Nov 21, 2011)

Verify the choke is working properly.

It's easy to get a gasket, insulator, etc. on backwards or upside down on this engine. Triple-check all and the governor spring, linkage, etc. 

Best image I have, sorry:


----------



## bwdbrn1 (Nov 24, 2010)

Forgot about the orientation of the gaskets and insulator. They have to go on the right way, and like Robert said, easy enough to get them on incorrectly.

Yes, you can buy a new carb, but GX carbs are more serviceable than GC carbs, plus, I'd recommend cleaning a new one just to insure it doesn't have anything foreign lingering in it.

The carbs on the GC engines are easy to get off, but a lot fiddlier to get back on than the GX carbs because the whole bolt comes off on a GC while GX carbs are held in place by bolt studs that remain on the engine block. 

So not to take away from Biketrax's thread, I started another to show a trick for removing and re-installing GC carbs.

http://www.snowblowerforum.com/foru...removal-re-installation-trick.html#post581833


----------

