Tuning a diaphragm carb on an HS40
Hey Andrew, this is just a shot in the dark, but I've heard from numerous Tecumseh guru's that the compression release on those cams is notorious for being troublesome. I was wondering if you checked the valve lash while it was apart? If the lash is off and the compression release was having issues, that could be your trouble.
it wouldn't hurt to double check the point gap, i have had a few incorrectly set the first time around, all they would do was idle, as soon as the throttle was opened even a tiny bit, it would die like someone hit the stop switch. turns out they were at like .024, not much but it made a huge difference. thats a tecumseh for ya:laugh:
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The new flywheel keys will be here tomorrow.
I took a look at the flywheel nut today. The flywheel doesn't look like it's back as far as it'll go. I think the first time I pulled it to check the points, I didn't put it back on tight enough and it bent something when it sheared the key. It would explain why I can't seem to get it tight enough now to keep it from sheering the keys now.
I'm going to lap the flywheel/crank with grinding compound in the morning. Hopefully, that'll help the flywheel seat correctly. I don't want to remove the head and oil breather unless I absolutely have to.
The paint job is already starting to look like shit from removing the three shroud bolts so many times. It's starting to flake around the head bolt holes. That's my fault for not going through everything before I painted it. I got excited and jumped the gun. Now I'm paying for it.
I took a look at the flywheel nut today. The flywheel doesn't look like it's back as far as it'll go. I think the first time I pulled it to check the points, I didn't put it back on tight enough and it bent something when it sheared the key. It would explain why I can't seem to get it tight enough now to keep it from sheering the keys now.
I'm going to lap the flywheel/crank with grinding compound in the morning. Hopefully, that'll help the flywheel seat correctly. I don't want to remove the head and oil breather unless I absolutely have to.
The paint job is already starting to look like shit from removing the three shroud bolts so many times. It's starting to flake around the head bolt holes. That's my fault for not going through everything before I painted it. I got excited and jumped the gun. Now I'm paying for it.
The engine is running like a champ. Some advice for you guys: Don't put your flywheel keys in backwards :doah:
I had spent about 20 minutes laboring on lapping the crank and flywheel with grinding compound before I thought about looking at the original photo of the stater plate. I noticed the flywheel key was facing opposite of what I had it at. Once I flipped that around, the flywheel slid right on and bolted up just fine. It started on the first tug.
I'm a little angry with myself, but glad that I figured it out before I took it somewhere and had them look at it.
There is also an issue with the kill switch, but I'm not sure what's going on with it. The bike won't run if the ground on the wiring harness is connected. I'm going to order a new switch for it and see if that fixes the problem.
I had spent about 20 minutes laboring on lapping the crank and flywheel with grinding compound before I thought about looking at the original photo of the stater plate. I noticed the flywheel key was facing opposite of what I had it at. Once I flipped that around, the flywheel slid right on and bolted up just fine. It started on the first tug.
I'm a little angry with myself, but glad that I figured it out before I took it somewhere and had them look at it.
There is also an issue with the kill switch, but I'm not sure what's going on with it. The bike won't run if the ground on the wiring harness is connected. I'm going to order a new switch for it and see if that fixes the problem.
