It surges and backfires at high idle with no choke. I smoothes out with one click of the choke so it's running lean. This is non adjustable carb, it don't look gummed up any suggestions?
It surges and backfires at high idle with no choke. I smoothes out with one click of the choke so it's running lean. This is non adjustable carb, it don't look gummed up any suggestions?
It's all there from when it was new. Looking in the manual that came with the snowblower, it has a repair kit part number 632760. Not sure if it needs a rebuild or not, I've read of the same thing happening after a rebuild. I'm trying cleaning with carb cleaner and compressed air to see if that does it but what is causing it?
The engine you have is an HMSK90-156543E. If it came into the shop I would be removing the carb and give it an ultrasonic cleaning. After cleaning, I would install a new float needle and seat before reassembling and installing back on the engine. Part number for the Kit is 631021B. You probably don't have an ultrasonic cleaner, so what I would do is disassemble the carb and remove all rubber parts and soak it in a bath of fresh gas and SeaFoam, 50/50 and then blow clean and rebuild. Attached is a manual which might help.
The engine you have is an HMSK90-156543E. If it came into the shop I would be removing the carb and give it an ultrasonic cleaning. After cleaning, I would install a new float needle and seat before reassembling and installing back on the engine. Part number for the Kit is 631021B. You probably don't have an ultrasonic cleaner, so what I would do is disassemble the carb and remove all rubber parts and soak it in a bath of fresh gas and SeaFoam, 50/50 and then blow clean and rebuild. Attached is a manual which might help.
The kit number you posted is a full rebuild kit, while the one I posted is a float needle and seat kit. No need to purchase a full kit, when you just need to replace the needle, seat and gasket. Some people say to replace everything, but I only replace the parts I need. It's up to you the direction you go.
I changed the seat and needle in the carb, cleaned and blew compressed air through all orifices and it's still surging. But now it does it under load which before it would only do it at high idle. I'm not sure if I got the governor arm in the proper position as I had it revving like crazy in the beginning but I have that under control. With that I wonder if it has something to do with the governor as I see that moving as well as the throttle as they are linked.
#8
Fish
Remove the bowl nut again, look closely at it. Take a small wire and thoroughly clean all of the tiny holes in it, and look for a tiny one at the top of the threads,
clean it too.
Remove the bowl nut again, look closely at it. Take a small wire and thoroughly clean all of the tiny holes in it, and look for a tiny one at the top of the threads,
clean it too.
I don't feel SeaFoam is going to do the job for you at this point. I suggest that you remove the carb again and go through this procedure after you have it ultrasonically cleaned or given it a 24 hour bath. I understand that you have done this once already, but something is either plugging one of the passageways or it is not assembled correctly.
Remove the carb, and then remove the float bowl. Check the float bowl jet (which is the bowl screw) and make sure the jets both horizontal and vertical are clean and open. Tip the carb upside down and remove the float pin and float with needle attached. Look in the float needle passage and you should see the red float seat at the bottom of the passage. This is where a #5 crotchet hook would come in handy as you need to remove this seat. If you have no hook, but compressed air, you can blow through the fuel inlet and try to pop the seat out. Put your thumb over the passage to prevent the seat from flying who knows where. No air or hook try bending a stiff paper clip to dig the seat out.
With the seat out clean the passage way with carb cleaner. Now you must find a drill bit slightly smaller than the passage way, to be used to press in the new seat. Apply a very, very small amount of a very light lube to the new seat. 3-1 oil or lighter, to help seat it better. Carefully insert the new seat in the passage way with the rings on the seat down toward the carb body. Slowly and carefully force the seat down with the back end of the drill bit. Once it is seated, check to see that it did not flip and the rings are up. If everything looks correct, attach the new needle to the float and install with the float pin centered. It everything is correct, the float should seat level to the carb body, when looking at it upside down. If everything looks good reattach the float bowl, making sure that both the bowl gasket and the nut gasket seal properly. Reinstall on the engine and test unit. Remember to have patience and take your time. Good luck, but I don't think you'll need it.
PS: *On the side of some Tecumseh carbs you will find a plastic cover. *Under this cover will be an idle jet. *Remove it and check to see that theist is open both horizontally and vertically. *You should be able to push the old float needle wire through the vertical opening.
