017 wont run when hot

[Kronker]

I have an older stihl 017 with almost zero hours on it.  I've had this problem for a long time so it just sits as I don't really need it.  Anyway, it will start and run usually for a few mins and then want to die.  To keep it running you have to blip the throttle constantly and once it stalls that's it.  I am leaning towards the carb needing replaced but could it be the coil.  Thanks for any info.  Would like to get it running to sell.

[beenthere]

Click on your forum name, and you will be where you can update your profile with at least your location.
Helps, as am sure you like it when reading others' posts that have location.;)

[deerslayer]

A coil usually has to be pretty hot to cut out and it isn't likely that blipping the throttle would keep it running.
First, try a different spark plug. Cheap and easy. Probably not the issue but it's on the list of possibilities.

Second thing I would do is check to see if you have spark after the saw quits. You may need to make a little jumper wire so you can ground the plug. I use a wire that has an alligator clip in one end (goes to cylinder fin) and the other end has a larger clip like what would come on a 1 amp battery charger. That goes around the threads of the plug.

The most likely issue is that it's fuel related. There is a very small screen in the carburetor that could be plugged, a fuel line could be cracked, the fuel filter could be plugged, etc. Also, if the carb is old, the diaphragms get hard and when they're stiff they don't work.

Something to start with at least. (before you do any of this, pull the muffler off and inspect the cylinder for scoring on the piston.)

Another thing to check while you have the muffler apart is to ensure the little spark screen is clean. If that's all carboned up the saw won't run. If it's nasty, leave it out, reassemble the saw and try it again...

[deerslayer]

The spark screen is under the little louver on the outlet end of the muffler in case you're not familiar with it.

[limbwood]

The holes in those carbs are so small they plug up pretty easy, soak it in cleaner for a few days and then try it.

[Kronker]

Thanks everyone. I'll try and get it sorted out this weekend. A good carb cleaning should be in order as well as checking all of the hoses while I'm in there.

[joe_indi]

I have an older stihl 017 with almost zero hours on it.  I've had this problem for a long time so it just sits as I don't really need it.

If it has been sitting very long probably the pickup body is nearly 100% blocked. Any fuel that was there in the carb would have dried up leaving some solid particles behind.
Try replacing the pickup body. On the handle close to the carb you will notice a small hole big enough for a small screwdriver. Insert a screwdriver and feel around for the adjustment screw there. Turn it anti-clockwise it its stop, I repeat, anticlockwise. Then turn it clockwise 1.5 to 2 turns.
Start it up, let it run at idle for some time, with occasional blips. If you are luck the blocks in the carb will clear out by itself. Otherwise you will need to clean the carb.

[Kronker]

Here's the latest. I took the carb off and inspected the fuel line. I didn't have a jug of carb cleaner to soak it but I did have some spray. I took it apart and everything looked clean. I sprayed everything good and let it sit. The diaphragm was pliable and the screen was clean. Checked the spark arrestor screen and cleaned everything up good. Reassembled the carb set the L screw 1 turn out and turned the idle screw 1.5 turns out. Started the saw let it warm up. It seemed rich and as it warmed seems to be dumping a lot of fuel. Tryed adjusting the L screw in to lean it some but made no difference. I could screw it in completely. It ends up flooding out and won't restart until dried out.
Any suggestions? I really appreciate the help on this, I'm not a small engine mechanic. Know enough to be dangerous.

[limbwood]

did you take the needle out and clean ? It could be not closing all the way and letting to much gas in at idle. There is a little spring under lever so dont let it go flying when you take the screw out.

[old2stroke]

My guess is the fuel inlet valve is sticking open.  It's the one operated by the fuel control diaphragm through a lever.  Remove it and if it has a rubber tip, make sure the tip is clean, and you can clean the orifice it seats in down in the cavity with fine silicon carbide paper wrapped around a toothpick.  If it doesn't  have a rubber tip, there is a rubber seat down in the bottom of the cavity that might be missing because someone blew it out with an air hose.  Make sure the control lever is set to the right height, usually the part of the lever that is touched by the button on the diaphragm should be level with the carb body with no gasket.

[ZeroJunk]

You can buy a new 017 carb on eBay for 11.99 shipped.

[Kronker]

Thanks for the help folks.  I took things apart again and did a bit more cleaning.  It seems to be better than it was but I need to get it into some wood to really test it out.  I think if it doesn't work this time I will do as Zero pointed out and get a new carb.  It seems funny that they are cheaper to replace than work on.  Thanks again.

[old2stroke]

Here are a few  other things I should have pointed out in my previous reply that will cause a flooding carb.  Has the inlet valve, lever and spring been installed correctly?  The pivot shaft for the lever has to be firmly held in place with its retaining screw and the spring has to seat on a dimple on the underside of the lever.  The lever has to be nice and free to move up and down.  If the end of the lever that is operated by the diaphragm has a forked end, it has to fit in a grove in the little metal button on the diaphragm or the diaphragm will be holding the inlet valve open.  Is the gasket on the right side of the diaphragm?  It should be between the diaphragm and the carb body (on the fuel side of the diaphragm).  If it is on the wrong side, the diaphragm will be too low and will again, be holding the valve open.  After putting the carb back together, place a short fuel line on the inlet fitting and try blowing into the carb.  If you can blow into it, there is still something wrong with the way the valve is seating or the control lever is set too high and needs to be adjusted.