Tecumseh 7 horse carb question

[jameswm1663]

Hello,

A while back I was given a Toro Powerthrow snowblower (with a Tecumseh HSK70), and managed to get it up and running--but it would only start if I sprayed starter fluid and ran it with the choke almost entirely open. It has run fine that way, but I heard from wise folks on this forum that something was up with the jets, and that the carb needed repaired or replaced. Since a new replacement is so cheap, I got one and installed it. I can get the machine to fire, but only with the choke open and with starter fluid. It cuts out right away. The fuel is new and clean. Am I missing some obvious thing here? Attached is a photo.

 

[Rivets]

Yes, you have an adjustable carb, which even new needs to be adjusted. Follow this procedure, skip the first part about checking the armature air gap. After going through this it should be running fine. Your initial adjustments are
1 1/2 turns out from lightly seated for the high speed needle and 1 turn out from lightly seated for the idle needle.

[FONT=&quot][FONT=&quot]Adjusting a carb[/FONT][/FONT]
[FONT=&quot][FONT=&quot]Ok, the first thing I would suggest is to reset the armature air gap with the single thickness of a business card, unless you are sure you have a gap of .010 inches. I don't normally recommend doing it this way, but in your case it may be best. Second, this is the procedure I always taught my students to adjust a carb with two fuel controlling needles.[/FONT][/FONT]
[FONT=&quot][FONT=&quot]1. Start the engine and move the throttle control to top speed.[/FONT][/FONT]
[FONT=&quot][FONT=&quot]2. Adjust the high speed needle (this is the one under the float bowl) clockwise very slowly until the engine starts [/FONT][/FONT]
[FONT=&quot][FONT=&quot] to bog down.[/FONT][/FONT]
[FONT=&quot][FONT=&quot]3. Back the needle out 1/8 turn, the engine should now run smoothly.[/FONT][/FONT]
[FONT=&quot][FONT=&quot]4. Now move the throttle control down to idle. If the engine stalls out turn the idle speed screw in one full turn,[/FONT][/FONT]
[FONT=&quot][FONT=&quot] restart the engine and bring the throttle control down to idle. If the engine is running to fast, turn the speed [/FONT][/FONT]
[FONT=&quot][FONT=&quot] screw slowly out until the engine seem to want to die and then in 1/8 turn.[/FONT][/FONT]
[FONT=&quot][FONT=&quot]5. Now with the engine running, adjust the idle needle out until the either gains in RPM's or starts to bog down. If[/FONT][/FONT]
[FONT=&quot][FONT=&quot] the engine gains in RPM's, continue to adjust out until the engine starts to bog down. At this time turn the [/FONT][/FONT]
[FONT=&quot][FONT=&quot] screw in 1/4 turn. Now the engine may be running to fast, so turn the idle speed screw out until you get an [/FONT][/FONT]
[FONT=&quot][FONT=&quot] RPM you like.[/FONT][/FONT]
[FONT=&quot][FONT=&quot]6. Now you must repeat step 5. If the engine bogs down right away turn idle needle back in to your starting point [/FONT][/FONT]
[FONT=&quot][FONT=&quot] and go to step 7. If it speeds up, repeat step 5 again.[/FONT][/FONT]
[FONT=&quot][FONT=&quot]7. Turn idle needle in until the engine bogs down and then out 1/8 turn.[/FONT][/FONT]
[FONT=&quot][FONT=&quot]8. Now the engine should run smoothly at all speeds.[/FONT][/FONT]
[FONT=&quot][FONT=&quot]9. To check, set the engine to idle, then quickly push the throttle control tohigh speed. If it dogs and does not [/FONT][/FONT]
[FONT=&quot][FONT=&quot] come to speed, open the idle needle 1/8 turn and repeat.[/FONT][/FONT]
[FONT=&quot][FONT=&quot]10. Set to go.[/FONT][/FONT]
[FONT=&quot][FONT=&quot][/FONT]
[/FONT]
[FONT=&quot][FONT=&quot]There are 2 reasons I have it done this way is, first the high speed needle controls the fuel going to the low speed circuit and second is that the idle needle controls how much fuel is used when going from idle to high speed. You should also review the section in the manual I posted before starting this procedure.
[/FONT][/FONT]
[FONT=&quot]Manual

[/FONT]https://www.mymowerparts.com/pdf/Te...P-4-CYCLE-L-HEAD-FLAT-HEAD-ENGINES-692509.pdf

 

[jameswm1663]

All good advice--but what do I do if it will not idle? It only fires until it burns up the starter fluid.

 

[Rivets]

Did you read the section on your carb in the manual I posted? Did you do the initial setting as instructed in the procedure? I’ll bet the answer is no. If after doing both and trying to do the procedure, make sure you have fuel flowing to the carb. Post back after doing both and then we will have a better idea as to how to proceed. Can’t help you out much more than that until you tell us what is happening.