HS40 might become gunshot victim

[capguncowboy]

I've been working on getting my HS40 up and running for some time now. For a week, I messed with the points system and finally got everything all tuned up. I put it on the motor, and it had good spark. I could hear the motor wanting to fire (the chug).

However, through some poor decision making involving me starting it with a power drill, I sheared the flywheel key and the flywheel came off (long story) and knocked the magneto/stator out of alignment. I was unable to get it to spark correctly after that. Finally I said :censure: it, and ordered a Nova II Electronic ignition system.

I installed it this morning. Once again, I have a really good spark. I haven't hooked it up to my ohm meter yet, but I'm certain it's ample.

No matter what I do the motor just won't start. :2guns::2guns::2guns::2guns: :censure: you engine!

It's getting gas. I've pulled the plug and it's wet. I've cupped the intake and it's getting air (I could feel it pulling. I checked the adjustments on the carb and everything is set up correctly. I have the valve cover tightened down, so it's not leaking. The compression is spot-on.

WTF else could it be!? I'm about 3-4 more attempts away from this thing becoming the next target at the local gun range.

 

[Havasu Dave]

What did you end up setting the timing at?

 

[capguncowboy]

.035 as directed in the manual.

I'll pull the valve cover and check it again. It's possible something got knocked out of time I guess. What else can I try at this point?

I'm really at my wit's end. There have only been a few things in my life when I've admitted defeat over figuring something mechanical or electrical out.

If this doesn't work, I am defeated. That 25lb boat anchor will have won.

 

[Havasu Dave]

If you set points at TDC .020, then set timing so the points break contact at .035, it should make fire, as long as you were able to win the battle with the magnets.

I understand your frustration at this. I went through the same thing. If the motor is all there, it's always better than a boat anchor.

Maybe you could send it to MB165 or ATKRIDER as a long block and have one of them take a look. No shame in that.

 

[capguncowboy]

I just took the flywheel off and had another look at it. I really have no way of setting the points or ignition timing at this point. I removed all of that when I put the electronic ignition on it.

I put the flywheel back on and tried to give it a go again. This time it sputtered a few times, but immediately died when I tried to give it a little throttle. I turned the idle screw all the way down but it didn't seem to make a difference.

This is currently how it's set up:

The condensor and points have been bypassed with the Nova 2. I know this is a different image (the coil is on the outside of the motor) but it's the same concept

If it's the timing, how does one adjust that while using this system? Turning the unit back and forth?

 

[Havasu Dave]

I am pretty sure that your original points type flywheel isn't going to work with this module. Nothing telling it to trigger at .035 BTDC, and no way to adjust it statically to do so.

I hope someone more knowledgeable chimes in. But I think that module was not the way to go. :shrug:

 

[capguncowboy]

That's exactly what this unit was made to do -- bypass the points system and condensor.

I've read threads on other sites where people have been successful at using these. It has spark... but I'm just not sure it's firing at the right time.

UPDATE: I just slightly adjusted the carburetor air mixture screw and it fired... it was running really sluggishly though, and giving it more gas did rev it up but it sounded really dirty. I'm starting to think it's this :censure: Chinese carb. Maddening!

UPDATE2: I just realized that I ordered this carb based on the Shroud saying it was an H40. Since then, I found out it's an HS40 motor with the H40 shroud. Would the carburetor be different?

 

[capguncowboy]

Today I adjusted the carburetor. I tightened both the jet screw and the air mixture screw all the way down and backed both out 1.5 turns. I pulled the flywheel and the key wasn't sheared but it almost was. I replaced it and put it all back together. It fired up.

It was running rough, so I adjusted the air mixture screw. When I turned it out, it got worse, so I tightened it about a half turn and it was running really well. However, it still won't open up when I lay into the throttle. It chugs and sputters. I played with the adjustments some more, but nothing seems to help. I'm really not a motor guy (I feel like I'm getting there though, despite my wishes). This is baffling to me.

Clearly, the timing is no longer an issue, and the electronic points system is working great. It has to be the carb, but I'm not sure what it is.

Does anyone have any suggestions?

Thanks!

 

[capguncowboy]

And it sheared another pin. What causes that? That's three now

 

[Stangrcr1]

Ignition timing.

Also, before you put a new key in, lap in the flywheel to the crank taper.

 

[capguncowboy]

Ignition timing.

Also, before you put a new key in, lap in the flywheel to the crank taper.

I'm not sure what you mean? How does one lap in the flywheel?

Nevermind, I found it. I've never heard of doing this before. Hopefully this will help solve my issue

 

[creia]

And it sheared another pin. What causes that? That's three now

Not tightening down the flywheel nut adequately (too loose). Are you using a torque wrench and tightening to Tecumseh specs?
Michael

 

[capguncowboy]

Not to tecumseh specs using a torque wrench, but I'm cranking it down pretty tightly. I used an 18v dewalt impact gun. There is no play in the flywheel at all -- at least not that I can tell. And when you loosen the nut, the flywheel doesn't come off on it's own

 

[creia]

Not to tecumseh specs using a torque wrench, but I'm cranking it down pretty tightly.

I believe that is your problem right there. The proper torque of that flywheel nut is critical.
Michael

 

[charliechaindrve]

I'm having the exact same problem, with the exact same model of engine. What is the tecumseh torque spec? I'm really at my wits end as well. I got the darn thing to run one time, but it ran like crap. Idled way high (I know, that's the idle screw in the carb) and it just didn't sound quite right when it was running. When I tried to bring the idle down, it died and I haven't been able to get it running since.

 

[capguncowboy]

Mine turned out to be the ignition timing. After exhausting what I felt was every option I gave up and sent it off to another member. He changed the condenser and points and reset the timing. It started on the first or second pull after that.

Don't give up. Odds are it will be something simple. It gets frustrating but it's worth it once you get it to idle and rev properly the first time.

 

[Phil1958]

http://www.barrettsmallengine.com/manual/tecumsehlheadmanual.pdf

this has everything you need. :thumbsup:

 

[RUSigX]

I've got a sore arm and a high level of disgust and what I believe to be a similar issue. My bike was given to me from a friend, it's a Rupp Roadster 2 with a Tecumseh HS40. I've rebuilt the carb, new spark plug, air filter, fuel line, added a new condensor, new points, and a new coil. I set the points gap to .02 when I replaced them.

The plug gets good spark but the HS40 wont crank to save it's life and I'm about at the end of my rope! Out of 100 pulls you may get it to fire and idle for just a moment. A lot of times when I'm pulling on it, it will kick back and rip the pull start out of my hand...:censure: that hurts! As soon as that happens the next couple of pulls are your best shot at getting it to crank.

Could my timing be off? I have no idea how to check or set it. Just not sure what else could cause this!

 

[capguncowboy]

I've got a sore arm and a high level of disgust and what I believe to be a similar issue. My bike was given to me from a friend, it's a Rupp Roadster 2 with a Tecumseh HS40. I've rebuilt the carb, new spark plug, air filter, fuel line, added a new condensor, new points, and a new coil. I set the points gap to .02 when I replaced them.

The plug gets good spark but the HS40 wont crank to save it's life and I'm about at the end of my rope! Out of 100 pulls you may get it to fire and idle for just a moment. A lot of times when I'm pulling on it, it will kick back and rip the pull start out of my hand...:censure: that hurts! As soon as that happens the next couple of pulls are your best shot at getting it to crank.

Could my timing be off? I have no idea how to check or set it. Just not sure what else could cause this!

I'll save you a lot of trouble. It's likely that your timing is off. It doesn't take much for it to throw it off and keep it from running. First off, check your flywheel key. If it's sheared or even bent, you need to replace it.

Secondly, set your ignition timing. If you don't have a tecumseh dial indicator, you'll need to remove the head from your engine. Rotate the motor to top dead center (the piston will be at it's highest position possible). Then rotate it back until your piston is .035 (I think that's the tecumseh recommended spec) before top dead center. I used a gap-gauge on mine. While the piston is in this position, you'll want to rotate your coil assembly left or right until it opens your points all the way up. Then set your points gap to .020"

Button it all back up and give it a whirl.

Through the entire process I pulled my starter at least 500 times. I couldn't move my arm afterwards. I ended up sending it to another member and they were able to get it to start right up by following the instructions to a T.


The other option is to sell that old Roadster to me. You probably don't really want it anyway :laugh:

 

[RUSigX]

Thanks for the reply capgun! I should note that I did not remove or adjust the stator on the motor when I replaced the points, condensor, and coil. Now that's not to say that it wasnt off before I messed with it.

When I had the fly wheel off previously I didnt notice any issues with the key. That doesnt meant it's not bent. I can probably pick one of those up at any lawnmower repair?

I've never removed the head on a engine like this before, will this ruin the head gasket? I dont have a dial indicator but I do have a micrometer. I am a little confused on this statement

'While the piston is in this position, you'll want to rotate your coil assembly left or right until it opens your points all the way up.'

I might just let you have this thing :angry:, it's probably a 71' model or so and all original but it looks a little tired. Probably hasn't run in at least 20-25 years.