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accurate machinery
01-28-2013, 12:32 PM
I am trying to fix a friends Craftsman snow blower, it is powered by a 8HP Briggs overhead valve engine, the stamped production is 010804, so it is a 2004 as I understand. It has a one speed carb, no throttle control, no points. Just a coil triggered by the flywheel. The machine runs good when it runs, but to start it, I have to hold the throttle closed with my hand while pulling the cord, and even then it only will start sometimes if I warm it up (bring it inside). The spark is pink and erratic not bright blue like I would like. I have cleaned the carb, it is getting fuel and has good compression, I think the coil is failing. Do these coils go bad? I am not use to replacing coils but I have been out of the repair business. Any help would be greatly appreciated! *trucewhiteflag*

Patriot Services
01-28-2013, 12:48 PM
They do fail sometimes but try this first. Remove the coil and make sure all the mating surfaces are good and clean. Reinstall and set the correct gap (folded piece of paper works fine). See if that improves spark quality.
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Landrus2
01-28-2013, 12:52 PM
Briggs and cold don't mix very well. First thing I would replace would be spark plug.

accurate machinery
01-28-2013, 12:57 PM
Sorry, I forgot to mention that I did replace the spark plug. I sanded the minor rust on the flywheel magnet. Thanks, Ken

dutch1
01-28-2013, 01:08 PM
Follow Patriot's instructions--what he means is to clean the coil and mounting bosses that the coil is mounted to, Over time corrosion develops and contibutes to a bad ground.

In addition, you may try pulling the kill lead to the coil and check spark.

Landrus2
01-28-2013, 02:20 PM
Sorry, I forgot to mention that I did replace the spark plug. I sanded the minor rust on the flywheel magnet. Thanks, Ken

OK we having some progress have you tested it for spark you say you have pink colored sparks that is due from 95 octane fuel no problem there.
Do you have spark :waving:

piston slapper
01-28-2013, 02:43 PM
OK we having some progress have you tested it for spark you say you have pink colored sparks that is due from 95 octane fuel no problem there.
Do you have spark :waving:

OK...I'll bite...
Where does it say 95 octane caused or causes pink colored sparks...???:dizzy:

piston slapper
01-28-2013, 04:05 PM
No certification OK :hammerhead:So tell you story why do sparks get pink colored:rolleyes:

My apologies in advance to the OP...again...
I havent listed my certifications in over a week...this guy that has been a member of this site since 2006 must have forgotten...more than that I reckon...

Kohler Certified Expert Tech since 1998...yes I have an update school next week..
Briggs MST..Kawasaki Schools 98 to present...Hydrogear schools...Im sure Im leaving a few out..??
In any case..I cant figure out how 95 octane...or anything to do with the fuel can affect the color of the spark...
Im only familiar with yellow and blue sparks...we dont have pink sparks around here..
Yellow is weak..Blue is good...Pink ??? the lighting must be playing tricks on his eyes.

The 8hp Briggs in this thread has an inductive coil...clean the coil mounting areas and set the airgap to .010..with the kill wire disconnected...pull the rope...if you dont get a nice blue spark...coil is weak...

accurate machinery
01-28-2013, 04:25 PM
Thanks for the replies, I am guessing the owner has had this problem for a while, the electric starter is worn out and the pull rope is starting to frey. The gap on the coil has been set, the flywheel sanded and I have a weak looking spark. I know a spark should be bright blue, so I am suspect of the coil, since it seems at times to have no spark, wont start at all. Then with no reason it will start. That is what makes me suspect the coil, I am not used to replacing a coil and didn't want to go buy one to find out that it is not the problem, I also checked the flywheel key, it is normal. I know I have gas and compression, checked the valve clearances, all I have left is weak spark. :dizzy:

Patriot Services
01-28-2013, 04:36 PM
You still need to sand the coil mounts, not just the flywheel.
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ed2hess
01-28-2013, 08:41 PM
You still need to sand the coil mounts, not just the flywheel.
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That is good info I was working on an old Briggs on a tiller this morning and
no spark. I sanded the flywheel but didn't think about the coil mounting surfaces, thanks. This tiller was on the path to junk dealer, now it might have new life.

Patriot Services
01-28-2013, 09:36 PM
Growing up in the corrosion capital (Buffalo) I learned early on about good grounding and the gremlins it can cause. Electrical connections can never be too clean or too weatherproof.
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BigFish
01-28-2013, 09:49 PM
I am trying to fix a friends Craftsman snow blower, it is powered by a 8HP Briggs overhead valve engine, the stamped production is 010804, so it is a 2004 as I understand. It has a one speed carb, no throttle control, no points. Just a coil triggered by the flywheel. The machine runs good when it runs, but to start it, I have to hold the throttle closed with my hand while pulling the cord, and even then it only will start sometimes if I warm it up (bring it inside). The spark is pink and erratic not bright blue like I would like. I have cleaned the carb, it is getting fuel and has good compression, I think the coil is failing. Do these coils go bad? I am not use to replacing coils but I have been out of the repair business. Any help would be greatly appreciated! *trucewhiteflag*

Yes the coils can go bad.
Are you using a spark checker or a plug to check the spark? Could be a bad plug or a lousy ground on the plug/checker.
Also, the date code shows it being made on Aug(08) 4th(04) 2001(01)
And tells us nothing! It's best to post the Model & Type numbers.
Another thang......sanding the magnets and coil legs doesn't do a dam thing towards increasing the spark!
As Slapper suggested, a good ground is needed.
Is the coil set to .010 or so?
Prolly time to replace the coil.

Michael J. Donovan
01-29-2013, 10:19 AM
ok, let's get back on point and the discussion at hand...no need to disrupt the thread and take it off topic

thanks, we would appreciate it :waving: