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8hp Briggs/7hp Briggs ignition issues


Legal v8's Avatar
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09-09-07, 07:21 PM   #1  
8hp Briggs/7hp Briggs ignition issues

my 7hp (170432) had no spark, so I replaced the coil and points set (new) from my 8hp (190432). The 7hp runs fine. I replaced the points/coil with the solid state coil #398811 in the 8hp and now it will not run. It backfires and spits sometimes and I get some fuel dripping from the bottom of the carb. I am certain the flywheel key is intact and not sheared and I tried starting with the kill wire connected and not connected, and two different spark plugs getting the same result. What could be wrong? I installed the coil as the directions stated. I can't stop scratching my head.. any thoughts?

 
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09-09-07, 07:59 PM   #2  
Sounds to me like either the key (which you sated you're certain it's ok), or the carb is flooding.


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09-10-07, 05:22 PM   #3  
Posted By: cheese Sounds to me like either the key (which you sated you're certain it's ok), or the carb is flooding.
The 8hp ran fine before the coil swap. I'm going to pull the flywheel again and make sure the key is fine.

 
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09-10-07, 08:03 PM   #4  
Well, I thought a new flywheel key would last longer than it did, but in fact it was sheared off. I replaced it with another new one and it now runs again. Thanks for your reply.

 
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09-10-07, 08:44 PM   #5  
You have to really torque the flywheel bolt on. I mean REALLY tight! Or the key will just shear again. I don't know the exact ft. lbs (65 I think?)

 
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09-11-07, 12:42 PM   #6  
65 foot pounds is correct on the flywheel nut torque.

 
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09-11-07, 06:43 PM   #7  
Alright. I'll double check it and make sure its tight enough. How exactly are you supposed to torque that starter clutch on there and with what? I've been using a channel-lock pliers and just crankin it down.. (my engine doesnt have a nut, just a washer and recoil starter clutch hold the flywheel on)

 
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09-11-07, 07:50 PM   #8  
Can you post a picture of your setup, I have never heard of yours. Have a good one. Geo

 
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09-11-07, 10:15 PM   #9  
Briggs gas a special tol for turning the cranking ratchet, but you can use the channel locks if you can get a good enough grip, and hold the flywheel well enough. You won't be able to get a torque reading this way, but just tighten the stew out of it...that'll be close enough.


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09-13-07, 07:53 PM   #10  
Posted By: geogrubb Can you post a picture of your setup, I have never heard of yours. Have a good one. Geo
If you have Adobe Acrobat Reader, look at the illustrated parts list here: http://www.briggsandstratton.com/ipl...100/MS5850.pdf
its part #66 on page 6 of the .PDF... Most briggs engines I've ever had or worked on had this style of start mechanism.

 
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09-14-07, 09:29 AM   #11  
Legal v8, I see now, I was thinking vertical shaft mower with the cup and stuff. Thanks for clearing up my confusion. Have a good one. Geo

 
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09-14-07, 11:47 AM   #12  
You can purchase a Briggs starter clutch tool, part number 19244 at any Briggs service shop for around $11 and at the same shop, if they handle Stens aftermarket parts, they have a flywheel holder for this engine, part number 750-083 for around $33.

 
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09-14-07, 12:05 PM   #13  
Thanks for all of your replies. I will look into those tools when I get back from my weekend camping trip. have a great weekend folks!

 
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