Cheap ignition coils
Posted June 15, 2017 - 01:50 PM
I put the battery on charge for awhile as I had been running it down a bit with all the attempts.
Right after full charge and before the battery settled back down ( reading 13.86 volts ) the motor spun a little faster and started right up, running fine as usual. Same deal this morning cold motor and a full charge battery, it started after several revolutions. Then when warm won't restart despite the motor turning over fast.
My theory now is the coil is weak enough that the carb cleaner having a lower flash point than gas helped it start with less spark and the extra bit of voltage in the battery after a charge helped the motor spin just a bitter faster increasing the voltage a bit from the coil and allowing it to start and once running the increased rpm allows the coil to put out enough voltage to run decent.
Your thoughts?, And any leads on where to get a good used Oem Briggs magnatron or better yet brand new Oem Magnatron would be welcome.
I think most of the new " replacement " coils out there on eBay will be the same Chinese quality labeled under different names.
- Mark 149 J. said thank you
Posted June 15, 2017 - 03:33 PM
Edited by boyscout862, June 15, 2017 - 03:34 PM.
Posted June 15, 2017 - 03:35 PM
I am always of the mindset you pay for what you get, in my years of selling so far the only coils that I have received defective were aftermarket ones, so far no OEM's have ever failed from what myself or customers used.
I do stock OEM B&S, if interested send me a PM so I can quote you shipping to Canada
- Alc, WrenchinOnIt, MolonLabe and 1 other said thanks
Posted June 15, 2017 - 08:47 PM
I have PMed Bolens 1000 and hope to get one from him.
- Bolens 1000 and Cvans have said thanks
Posted June 15, 2017 - 11:10 PM
Not to step on any toes here folks, or detour business, but I have never had problems with any of Oregons parts.
Before giving up on that unit, try setting the coil gap with an index card in between. Run the magnets to the coil when you tighten down the coil bolts, after they are tight, spin flywheel to remove card.
Lastly, don't completely reassemble the motor, you can check the spark with all that junk off, if it dont work, atlest you won't have to go through teardown again.
Try this 1st, nuthin to loose;) Keep us posted.
Edited by stiemmy, June 15, 2017 - 11:15 PM.
Posted June 16, 2017 - 05:25 AM
When you were cranking for long periods of time to you pull the plugs to see if there were wet ( gas fouled ) ? How's the compression , valve lash ?
Posted June 16, 2017 - 08:54 AM
Rainy weekend coming up so I may have time to get into it. I will do a compression test first and double check the air gap next and go from there.
Story and or rant to continue, grin.
Posted June 16, 2017 - 09:55 AM
A coil is a pretty simple thing. Why would one be weaker? Thinner wire? Fewer windings? Poor plug wire?
Posted June 16, 2017 - 10:19 AM
Week condenser? Don
Posted June 16, 2017 - 02:44 PM
In any event I have a OEM coil and a carb kit on the way from Bolens 1000. I don't think the carb is part of the problem, but I wanted one on hand anyway.
Posted June 20, 2017 - 11:02 AM
I've seen an engine that won't start after it gets warm. One that I owned was caused by a cracked coil, the other was caused by low compression and would not warm start. It ran as long as you did not turn it off.
- Rock farmer said thank you
Posted June 20, 2017 - 01:42 PM
Would seem to me that is decent enough to start? Briggs does not publish compression specs for the L head twins as I understand there is a sort of compression release built into the way the cam lobes are ground keeping a valve slightly open during the compression stroke. If that is true, then I am guessing those readings are decent and why the preferred test is a leak down test, but again I have no data to compare my findings if I rigged up something to do one with.
Posted June 23, 2017 - 09:03 PM
I decided to fiddle with the Oregon coil I installed a few months back first. Checking the air gap again one leg was around 10 thou and the other around 13 thou. I set them a little closer and made sure they were equal at 8 thou and turned the key, it consistently started after about 5-6 revolutions. Ok that's great but I wanted to compare with the Briggs coil. I switched out the coils set the Briggs at 10 thou and turned the key.
Much quicker starts, maybe 2 revolutions max.
So I guess I'll keep the Oregon as a spare but it seems to me it doesn't have as much umph as the Briggs. I just need to reinstall the cowling, fan etc, drop the motor back on it's mounts and reconnect the drive shaft tomorrow.
- Bolens 1000 said thank you
Posted June 23, 2017 - 09:25 PM
Glad to hear it worked out for you!