Hs40 carb replacement

Mini Bike & Go-Kart Parts

#23
Just setting the gap won't do on a Tec. Read up on timing the engine correctly. I'm not sating you dont have a carb issue, but I can;t stress enough that the timing has to be correct with these for them to run correctly.
Looks like I need one of those nice dial indicators that thread in the spark plug hole
 
#25
I prefer just pulling the head and getting an accurate reading. The Tec tool works, but is more difficult to orient than it is worth in my eye.
im not sure I understand the “orient” part....put the foot over the piston....now on h30 and smaller you’ll have to pull the head....
 
#28
Pulling the head you will replace it and probably need to anyway... and in reality pulling the head is probably the best and truest way?!? But I find no issues using the Tecumseh tool....except on smaller engines....and I’ve had pretty good luck
So far....just an opinion....
 
#29
Just setting the gap won't do on a Tec. Read up on timing the engine correctly. I'm not sating you dont have a carb issue, but I can;t stress enough that the timing has to be correct with these for them to run correctly.
My buddy brought home his dial indicator home from work so that is what I am going to do this weekend
 
#30
My buddy brought home his dial indicator home from work so that is what I am going to do this weekend
My points were out of spec. Reset and cleaned. Set the timing and put it all back together and guess what.... Won't start. I can't make this up. This happened when I initially put new points and condenser on months ago. It ended up being that the threaded piece where you attach your coil and condenser dropped back a bit so when I tightened the nut down it wasn't making contact with the spring. I assume that is the issue again. Who said these were ready to work on? Lol
 
#32
My points were out of spec. Reset and cleaned. Set the timing and put it all back together and guess what.... Won't start. I can't make this up. This happened when I initially put new points and condenser on months ago. It ended up being that the threaded piece where you attach your coil and condenser dropped back a bit so when I tightened the nut down it wasn't making contact with the spring. I assume that is the issue again. Who said these were ready to work on? Lol
That is why I said a while back that maybe you should check the points for pitting/gap and condenser etc. It is crazy that you are having all of this trouble. As I said before I've had several that have literally sat for decades and usually within an hour or so I can have them up and running fairly decent no problem. For starters I would of just cleaned up what was originally on it and filed and set the points and went from there. Even with cars,trucks,tractors etc most of the new points on the market today are poor quality compared to lets say vintage nos ones from back in the day. Send it to me I will getting running good for you if you pay the shipping.
 
#33
My points were out of spec. Reset and cleaned. Set the timing and put it all back together and guess what.... Won't start. I can't make this up. This happened when I initially put new points and condenser on months ago. It ended up being that the threaded piece where you attach your coil and condenser dropped back a bit so when I tightened the nut down it wasn't making contact with the spring. I assume that is the issue again. Who said these were ready to work on? Lol
I guess spring is wrong word. If your looking at your points to the left of the set screw is that flat piece that connects to the threaded piece that you attach your coil and condenser to. That backed out of it's spot and was not making contact with that piece that metal piece that goes to the points from that terminal.
 
#34
That is why I said a while back that maybe you should check the points for pitting/gap and condenser etc. It is crazy that you are having all of this trouble. As I said before I've had several that have literally sat for decades and usually within an hour or so I can have them up and running fairly decent no problem. For starters I would of just cleaned up what was originally on it and filed and set the points and went from there. Even with cars,trucks,tractors etc most of the new points on the market today are poor quality compared to lets say vintage nos ones from back in the day. Send it to me I will getting running good for you if you pay the shipping.
They were so burnt when I checked them. I put a new set of nos points and condenser on. I always use nos if I can find it. Thanks for your insight
 
#36
Are you totally sure that it is a carb problem ? Did you check for pitted points,gap on points,and or timing etc ? I know the China carbs are not that great but I've really never had too much trouble with them or even with the Tecumseh originals once they are cleaned and or rebuilt etc. I've had/have several engines that have literally sat for decades and I can usually have them up and running very well within just a few hours.
Set the timing. Put it all back together, no spark. This started out fun but now it is not. Is there anyone close to Philly that can help out and take a look at this thing? I just wanted to do something cool with my grandsons and it has turned into a chore. No fun. I admit I am a novice but you guys and YouTube helped me out. I just don't get it. Very frustrated
 
#37
Set the timing. Put it all back together, no spark. This started out fun but now it is not. Is there anyone close to Philly that can help out and take a look at this thing? I just wanted to do something cool with my grandsons and it has turned into a chore. No fun. I admit I am a novice but you guys and YouTube helped me out. I just don't get it. Very frustrated
These can be tricky to get right. FWIW I always pull the head.
After setting the ignition timing, I put the flywheel back on hand tight and spin it over by hand to check for spark. Just connect the spark plug and rest it on the top of the block.
That way if there is no spark, it’s easy to disassemble and make adjustments, rather than putting everything back together and have to pull it all apart again.
In the flathead service manual (available on this site, link below) there are specific instructions to set the ignition timing.
If you follow those instructions carefully, you should be fine.

http://www.smallenginesuppliers.com...cumseh_L-Head_Engines_Service_Information.pdf

Good luck, you can do this. Plenty of great people here to help
 
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#38
These can be tricky to get right. FWIW I always pull the head.
After setting the ignition timing, I put the flywheel back on hand tight and spin it over by hand to check for spark. Just connect the spark plug and rest it on the top of the block.
That way if there is no spark, it’s easy to disassemble and make adjustments, rather than putting everything back together and have to pull it all apart again.
In the flathead service manual (available on this site, link below) there are specific instructions to set the ignition timing.
If you follow those instructions carefully, you should be fine.

http://www.smallenginesuppliers.com...cumseh_L-Head_Engines_Service_Information.pdf

Good luck, you can do this. Plenty of great people here to help
I have the manual thanks. I had spark before I set timing. Points and condenser and plug are new. Coil tested fine at my buddies work. Even if timing was off I should still get spark right? I set to .035 btdc. Do you need to set the gap between coil and flywheel? If so I don't know how. Could that be a problem since the coil is inside not outside of flywheel
 
#39
Did you use a multimeter and rotate the stator plate? Did you make sure to remove all leads from the points and tighten the nut back down before hooking up the multimeter?
You should not have to worry about the air gap on a points engine.
When I do this, there are 3 main steps—
1. Set the points at .020” with the points on the high side of the points cam.
2. Position the crank so that the piston is .035” BTDC on compression stroke.
3. Remove leads from the points stud, attach multimeter to points stud, and to ground. Loosen stator bolts and rotate stator plate until the circuit just breaks, tighten stator bolts.

If you have doubts about the points, you can use the multimeter to make sure they are opening and closing and power is getting through.

Is it possible that the kill switch wire is touching ground somehow? You won’t get any spark if that is the case
 
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#40
Did you use a multimeter and rotate the stator plate? Did you make sure to remove all leads from the points and tighten the nut back down before hooking up the multimeter?
You should not have to worry about the air gap on a points engine.
When I do this, there are 3 main steps—
1. Set the points at .020” with the points on the high side of the points cam.
2. Position the crank so that the piston is .035” BTDC on compression stroke.
3. Remove leads from the points stud, attach multimeter to points stud, and to ground. Loosen stator bolts and rotate stator plate until the circuit just breaks, tighten stator bolts.

If you have doubts about the points, you can use the multimeter to make sure they are opening and closing and power is getting through.

Is it possible that the kill switch wire is touching ground somehow? You won’t get any spark if that is the case
I did all that as you explained. I found tdc with the dial then turned it back then came up to .035. no wires connected. Kill switch is brand new and no shorts. It ran before I set the timing
 

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