quantum start problem

[wilson.campbell]

Brig and Strat quantum with auto choke and primer.

Would apprec some help and advice. Cleaned carb and replace sparkplug (as faulty). Mower worked for one long cut with multiple starts. Week later started for couple of second and I turned it off to adjust height setting and now it will not start no mater what (fuel and oil levels ok). Have checked and spark plug OK (using multimetre) and there is current from the magneto (used tester that lights up). Motor does not even seem to turn over. Just pull card and magnet etc works but no ignition. Tried with out filter, tried to spray some carb cleaner into carb in case it is not priming (has auto choke and primer). Fuel is held in can so no chance of water in fuel etc. Auto choke arm sitting OK and moving correctly. Also loosened carb bolt to check if fuel in bottom and their was (let it empty). Checked again after trying start again and there was fuel in it again. I am now stuck. Any ideas.

 

[wilson.campbell]

Brig and Strat quantum with auto choke and primer.

Would apprec some help and advice. Cleaned carb and replace sparkplug (as faulty). Mower worked for one long cut with multiple starts. Week later started for couple of second and I turned it off to adjust height setting and now it will not start no mater what (fuel and oil levels ok). Have checked and spark plug OK (using multimetre) and there is current from the magneto (used tester that lights up). Motor does not even seem to turn over. Just pull card and magnet etc works but no ignition. Tried with out filter, tried to spray some carb cleaner into carb in case it is not priming (has auto choke and primer). Fuel is held in can so no chance of water in fuel etc. Auto choke arm sitting OK and moving correctly. Also loosened carb bolt to check if fuel in bottom and their was (let it empty). Checked again after trying start again and there was fuel in it again. I am now stuck. Any ideas.

UPdate:

Tried following. Spark out, throttle low, pull cord couple of time to clear a flooded engine (wait 5 minutes otherwise this will not work). Place spark in. Tape auto choke leveler into close position. When pulled OK but with a little misfiring. Let run for a minute and stop it. Try again and it will not start, will not start with tape removed or any setting on the throttle including choke position. This has worked twice now. Do you have to get it running for a very long time to overcome a badly flooded engine?

 

[wilson.campbell]

UPdate:

Tried following. Spark out, throttle low, pull cord couple of time to clear a flooded engine (wait 5 minutes otherwise this will not work). Place spark in. Tape auto choke leveler into close position. When pulled OK but with a little misfiring. Let run for a minute and stop it. Try again and it will not start, will not start with tape removed or any setting on the throttle including choke position. This has worked twice now. Do you have to get it running for a very long time to overcome a badly flooded engine?

update again: Got started using technique above. Ran for 15 minutes cutting grass. Had to stop to empty collector. Would not start again and tape no longer needed as choke now correct pushed forward by auto choke. Tried the above again and it started again. Cut grass for 5 minutes and then shut down to move to another park of garden. Had my lunch. Would not start using the technique until I tried it the second time. This is confusing, there is no leaking fuel from the carb at the air filter side so float etc should be OK but engine seems to be flooded every time a try to start it.

Spark plug shows no sign of problems, not wet and no dark areas of fouling.

Anyone any ideas?

 

[Rivets]

Carb needs to be cleaned and replace the float needle and seat. Here's the procedure I recommend.

Needle and seat replacement

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.

I would either give the carb a good 24 hour soaking or have it ultrasonically cleaned at this time.

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. *Next check to make sure that the float does not have any liquid in it. *If it does, replace. *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 the jet is open both horizontally and vertically. *You should be able to push the old float needle wire through the vertical opening.

 

[pugaltitude]

Your autochoke thermostat could be siezed, sticking or out of adjustment. http://www.lawnmowerforum.com/toro-wheelhorse-forum/24253-toro-recycler-will-not-start.html

Also quite common with autochoke is if the flywheel key is sheared then it causes bad starting symptoms like a carb problem.

Another thing is the metal spark plug cap causes a difficult start due to resister breaking down.

Replace with normal terminal and boot.

 

[wilson.campbell]

Carb needs to be cleaned and replace the float needle and seat. Here's the procedure I recommend.

Needle and seat replacement

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.

I would either give the carb a good 24 hour soaking or have it ultrasonically cleaned at this time.

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. *Next check to make sure that the float does not have any liquid in it. *If it does, replace. *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 the jet is open both horizontally and vertically. *You should be able to push the old float needle wire through the vertical opening.

Hi,
Thanks for the responding. When I cleaned the carb I did replace the Needle and seat with a new one In fact the carb was very clean already with no dirt or staining. I damaged the seat on getting it out and did not realize until I had re installed carb and added petrol/gas. Then petrol was leaking out of the carb at the air filter side. I bought a new needle and seat and fitted and that problem was resolved. The floats was in very good condition

 

[wilson.campbell]

Your autochoke thermostat could be siezed, sticking or out of adjustment. http://www.lawnmowerforum.com/toro-wheelhorse-forum/24253-toro-recycler-will-not-start.html

Also quite common with autochoke is if the flywheel key is sheared then it causes bad starting symptoms like a carb problem.

Another thing is the metal spark plug cap causes a difficult start due to resister breaking down.

Replace with normal terminal and boot.

Hi,
Thanks for the response.

The auto choke seems to be working correctly. The thermostat is moving the choke pulley forward as the engine heats and goes back as it cools down. Does this mean it is OK?

Would sheared flywheel cause starting issues especially as I can get it started using the engine flooding recovery procedure I outlined. I have limited knowledge with this.

I used a spark tester that lights up and sits between the spark plug cab and the spark plug. It was lighting up fine. Would this mean it is OK?

 

[wilson.campbell]

Found the cause of the problem, I think The Governor spring was very lose. Bent the front holder back a bit to tighten it and it starts no problem. Just need to make sure RPM not too high. Now it is back firing every 2 to 3 seconds so need to find that problem now

 

[wilson.campbell]

Please note that there is a known problem with the spark plug cap. The metal version does not work most of the time hence on these lawnmowers everyone is getting starting problems. This is a known problem and should be fixed under warranty. If not, simply replace with the plastic version. Because I was working on the lawnmower I was unable to get it fixed under warranty but it is a cheap and easy fix.