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Discussion Starter #1
I just completed replacing the connecting rod in my H60 motor. It's my first time opening a motor....you might call me a youtube mechanic. As far as I can tell, everything went back together correctly. No parts left over. I lined up the timing marks, etc. In the youtube video, the guy removed the crankshaft and removed the piston from the bottom. His reasoning was to save replacing a head gasket if he went in from the top. I hammered a bit on the flywheel before coming to the conclusion that replacing a three dollar gasket was going to be a lot easier than fighting with the flywheel.

So the motor is back on the snowblower, and I just tried to fire it up. It won't start, and the problem appears to be lack of spark. I tested this by removing the plug and holding it against the engine block while engaging the electric start. So now I'm wondering if I reassembled something incorrectly, or possibly damaged something while hammering on the flywheel. Or maybe the old plug wire didn't like being jostled around on the bench.

I'd appreciate any advice on how to proceed/troubleshoot this....hopefully starting with the least invasive.
 

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Did you gap the points correctly? Magnets ok inside the flywheel? Do you maybe have the kill switch improperly wired? Do you have the key in the slot? Start with the simplest thing and go from there. That wojld be working backwards from what I just posted.
 

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Hello and welcome to the forum Tommy. Did you by chance remove the ignition coil? If you did, did you use a business card to set the air gap between the coil and the flywheel magnets? Also make sure the throttle is in the run position and you are using a KNOWN GOOD spark plug.
 

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Discussion Starter #4
I did not (knowingly) remove the ignition coil or any other electrical components. The plug is a few years old, but was working last week when I threw the rod. Correct me if I'm wrong...the coil and points are behind the flywheel? I didn't remove the flywheel, but did give some good whacks with a hammer and wood block before coming to the conclusion that it's will to not move was stronger than mine to remove it. I removed the head instead.

There is no kill switch or key. This thing is 50 yrs old......
 

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Sorry Tommy, I didn't realize it had a points ignition. Your engine will have or should have an ignition cutoff on the throttle control. When you move the throttle to off, the linkage contacts a small spring that gets grounded and shuts off the spark, so make sure the throttle is set to run. Posting your engine numbers stamped into the top of the recoil shroud near the spark plug will let us know more about the engine. The numbers may be underneath the electric start push button assembly.
 

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Discussion Starter #6
Sorry Tommy, I didn't realize it had a points ignition.
I don't *know* whether it has points or not...I only mentioned it because micah asked about them.

It's a Tecumseh H60-75003W motor. I'm not aware of a ignition cutoff on the throttle control. The throttle is a single cable going to the carb linkage. I've worked on the carb several times and never noticed a grounding spring. That doesn't mean it's not there...I just never noticed it. I didn't remove the carb during the dis-assembly I simply disconnected the throttle cable and the governor. I'm really hoping it's just something stupid that I missed, but I don't see any wires other than the plug wire.
 

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There has to be ONE other wire...it's the ignition kill, and its black, and will lead up under the flywheel...You may have inadvertently snagged that wire and its caught up under the shroud, and touching the block...thus grounding out the ignition [?]..
 

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it's will to not move was stronger than mine to remove it.
That is one of the funniest things I've read in a long time:D
If you post up a few pics of the motor, Grunt can set you straight on those Tecumsehs. Like most have posted, there is a wire from the underside of the flywheel that goes to the bottom of the throttle mechanism. Do you have a key switch? If you track that wiring, you'll see the wire that goes up inside the shrouding to the engine.
 

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Did you check the key on the flywheel? It could be sheared. Also, make sure the connector on the end of your plug wire is making good contact with the copper core. A good spark tool will give a better reading than holding the plug to ground. I would pan on pulling the flywheel to clean and reset the points as well. MH
 

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Discussion Starter #10
That is one of the funniest things I've read in a long time:D
If you post up a few pics of the motor, Grunt can set you straight on those Tecumsehs. Like most have posted, there is a wire from the underside of the flywheel that goes to the bottom of the throttle mechanism. Do you have a key switch? If you track that wiring, you'll see the wire that goes up inside the shrouding to the engine.
There *is* a wire I'd overlooked running from the underside of the flywheel to the carb/linkage. I've wiggled it around, and it doesn't seem to be touching the block. No, there's no key switch.

motorhead64 said:
Did you check the key on the flywheel? It could be sheared. Also, make sure the connector on the end of your plug wire is making good contact with the copper core. A good spark tool will give a better reading than holding the plug to ground. I would pan on pulling the flywheel to clean and reset the points as well. MH
I didn't make note of the key. I just removed the recoil mechanism and shroud. Then backed the nut holding the flywheel out till it was flush with the wnd of the shaft. Then I placed a wood block on it (the nut) and whacked it with a hammer. When it didn't budge after a few tries, I didn't use force, I got a bigger hammer.

It's starting to sound like the flywheel is going to have to come off...the thing I was trying to avoid. When I get the motor back on the bench, I can take some pics. Until then, any tips?
 

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Make copy cat mounts for the engine, or c-clamp it to your bench. I have air tools and cheat with a blunted tip on the chisel with the nut up flush with the threads (it will walk right off). If you don't have that, you can try the pry and wiggle approach.
Donyboy has a series on the tube, look at his points tutorial also.
 

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If you're still hoping to avoid removing the flywheel again...Then certainly check that kill wire leading from under the flywheel to throttle..."Disconnect" it...Check for spark at plug..or check it with an ohmmeter for needing to be "ungrounded"... If that checks ok, and you still have No spark at the plug...Then you need to re-remove the flywheel and see what went wrong..
 

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Discussion Starter #13 (Edited)
I have the motor back on the bench, and it looks like the flywheel key is sheared. I've attached some photos hoping somebody can confirm what I'm seeing. It looks like the flywheel may be rotated a bit over 90 degrees out of position. This would throw the timing off, right? But would that alone prevent me from seeing a spark? The photo doesn't show it well, but the kill wire seems to be clear of the block....not grounding out.

So the sheared key would explain why the flywheel was too difficult for me to remove, right? How do I get this sucker off now? Is there some sort of wheel puller I can use, or would that damage the flywheel?

H60.jpg
Key.JPG
Wire.JPG
 

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Have you downloaded the tecumseh manual?
http://www.asos1.com/tecumseh4hp/Tecumseh.pdf
it says

Thread the
appropriate flywheel knock-off tool part # 670103,
(7/16") or part # 670169 (1/2") on the crankshaft until
it bottoms out, then back-off one complete turn. Using
a large screwdriver, lift upward under the flywheel
and tap sharply and squarely on the knock-off tool to
break the flywheel loose. If necessary, rotate the
flywheel a half turn and repeat until it loosens (diag.
13).


The tool mentioned is a long nut to place the hammer loads along more length of the thread. Give another go as you did before with the regular nut. Do not pry too hard, but some pressure pulling on the flywheel while you are hammering on the engine shaft to break it loose.
If it moves even a hair, it will be loose.
 

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That does look like it is possibly sheared. It will mess up the timing and prevent the engine from running properly, but you should still have spark.
 

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That does look like it is possibly sheared. It will mess up the timing and prevent the engine from running properly, but you should still have spark.
I agree with Shryp, the key is sheared,and although the timing is way off, you should still have spark at the plug, but far to late. That is why it is so important to torque the flywheel nut correctly when reassembling.
 

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Discussion Starter #17
Give another go as you did before with the regular nut. Do not pry too hard, but some pressure pulling on the flywheel while you are hammering on the engine shaft to break it loose.
If it moves even a hair, it will be loose.
Thanks for that link to the service manual.

OKAY! I've got it off using the pry bar and hammer method (with the help of some PB Blaster.... Hopefully I can pick up a new key at a local repair shop. I'll clean and set the points. How can I troubleshoot the other components? I'm still concerned that I didn't see any spark when I turned it over.
 

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A sheared key also means the magnets on the flywheel are NOT timed with the closing and opening of the points. This has nothing to do with actual ignition timing.
Replace the key it should have spark. My guess is the key sheared because the flywheel was not tightened properly.
 

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Discussion Starter #19
That's what I'm hoping. Everything was working fine before the connecting rod blew. My local repair shop won't be open till Monday, so I guess it's a cliffhanger till then. Fingers crossed that I get this working before we get a Nor'easter. I want to thank you all for your support.....
 

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That's what I'm hoping. Everything was working fine before the connecting rod blew. My local repair shop won't be open till Monday, so I guess it's a cliffhanger till then. Fingers crossed that I get this working before we get a Nor'easter. I want to thank you all for your support.....
For the time being, just to test it with the spark plug out of the engine, you might be able to stick something in there temporarilty just to see if it will throw a spark.
 
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