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McCULLOUGH Blower/Vacuum XXV


Glened's Avatar
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11-14-08, 01:00 PM   #1  
McCULLOUGH Blower/Vacuum XXV

Engine won't start
The wire from the stop switch to the magnito reads grounded
when testing with an ohm meter. Could this be the reason that the engine won't start?

 
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cheese's Avatar
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11-14-08, 08:45 PM   #2  
That wire will read some continuity to ground...it's normal. Have you checked for spark with the spark plug body grounded to the engine block?


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11-17-08, 08:38 AM   #3  
Thanks cheese,
The continuity to ground is dead short and there is no spark with plug grounded to engine.

 
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11-17-08, 05:39 PM   #4  
Are you testing the wire with it disconnected from the ignition module??

If so, disconnect it and test again, also check for spark with this wire off of the module.

 
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11-17-08, 08:06 PM   #5  
Dead short as in 0 ohms may indicate a problem, but the best way to know for sure is to verify the plug is good, grounded, the air gap between the coil and flywheel is correct, and crank the engine to check for spark with the kill wire disconnected from the coil. If still no spark, then the coil is bad.


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11-18-08, 10:28 AM   #6  
Thanks again cheese,
This engine is very old, in fact I find that McCULLOUGH is now out of business and with that I probably won't be able to find parts. Just throw it in file 13 is what I may do but I am one to try to fix the problem. On checking the magnito ect. I find that the air gap was factory set at .60. There is no visable spark with the plug grounded to engine case and then I connected the plug wire thru multi meter to engine case and there is no indication on the meter when pulling the starter cord.
Glened

 
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11-18-08, 11:15 AM   #7  
Thanks for your reply 30yearTec
Yes,am testing with wire disconnected from stop switch. 10 ohms to ground (engine case)
No spark at spark plug, even tested for spark with multimeter , spark plug wire to ground.
Plug wire tested 150K to ground.
Air gap of magnito factory set at .60
Can't find replacement magnito if needed.

 
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11-18-08, 12:05 PM   #8  
Correction to last thread.
Multimeter not working correctly,switched to another which reads as follows
Stop wire to plug wire 887 K ohms
Stop wire to engine case 5.8 ohms
Plug wire to engine case 877 K ohms

 
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11-18-08, 12:15 PM   #9  
Correction to last thread
Multimeter not working correctly switched to another which reads as follows.
Stop wire to plug wire 887 K ohms.
Stop wire to engine case 5.8 ohms
Plug wire to engine case 877 K ohms

 
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11-18-08, 05:32 PM   #10  
Some McCulloch parts are still available, depending on the actual age of the unit. MTD purchased them, you can check their website and see if you can locate your blower there. It sounds to me like your Ignition module is bad and needs to be replaced. If you can locate the part, it may still not be cost effective on a unit that's very old.

 
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