QuestionQUESTION: I have a Briggs and Stratton Twin II I/C 16.5 HP Model # 42A707 Type 2653 Engine that I have been trying to troubleshoot for some time and was hoping for some direction.
The Engine only fires at the plug when touched with a ground – it then fires up and runs great until it is shut down and then the same thing over again will not start until ground is applied.
This is my 6th brand new Briggs and Stratton Armature (Coil) it does the same right out of the box. The Spark Plugs, Key Switch, Solenoid are New as Well. The Air Gap is set at .012 - the spark plug gap is set at .030 – the magnets on the Flywheel are fine (support the weight of a screwdriver). I have totally removed the wiring harness soldered all connections and reinstalled – found no shorts. I have removed all safety switches from the mower.
Briggs and Stratton themselves suggested the Diode on the Stator – checked it (Has ohm resistance in one direction and not the other – isn’t that what it is suppose to read?) why would this affect the Grounding for the ignition?
This wiring system has a dual Circuit Stator – One Circuit runs the Headlights the other charges the battery.
The only Items involved it the ignition circuit are the Magnets, Armature, Spark Plugs and the kill wire (Which is fine – no effect connected or not and it is not shorted) I believe The Engine Block is grounded because the Starter works fine.
Why does it take a Ground to draw the fire from the coil and run fine afterwards?
6 Coils in a row can’t be all Bad – can They?
Any Help would be greatly appreciated – this has been a personal challenge to try and figure this out..
ANSWER: Hello Kerry:
What are you Grounding? Where are the 2 Ends of the Ground Wire Connected? If you are Grounding the Engine, then Run a Separate Ground Strap to the Engine from the Frame. A Starter can Make a Ground Connection because it Demands Current to Operate. A Coil Does Not Demand Current, it Just Requires a Ground. Once a Ground is Made, then it can Operate. If there is Oil, Rust and Dirt Under the Engine Mounting Areas, this Reduces the Ground Effect for the Engine. I have Engine Ground Straps Installed on All my Equipment to Prevent the Grounding Problem. I have Discovered Over the Years that Losing Ground has been a Major Cause for a Lot of Burnt PTOs, Bad Stators, ect. Are you Installing the Coils with the Side Marked Out/Up Showing? If you Hit a Snag or this Does Not Correct the Problem, I am Here if You Require More Assistance. Hope this Helps. Let me Know What Happens, Please. May the All Mighty Bless You and Yours. Thanks.
Good Luck
Respectfully
John
PS: I am Allowed to Answer 10 Questions a Day. If you See I am Maxxed Out, then Try Submitting your Question at or Just After 8pm EST (US). My New Day Starts then. Thanks.
Respectfully
John
---------- FOLLOW-UP ----------
QUESTION: John - Thanks for taking the time to respond to this communication - Greatly Appreciated.
Sorry I had failed to be more specific - I am actually applying the Ground from the engine block itself (Bolt on the Head) to the Spark Plug Wire terminal - where the terminal snaps onto the spark plug.
I have applied the ground to the base of the spark plug itself with no results. I discovered this while Cranking the engine (it not starting)and touching my test light to the spark plug wire to see if it was get fire and it started.
Sir the "this side out" is facing up on all the new coil installations that I have done - I have been compulsive about making sure of this due to the number of times I have changed the coil.
I will and haven't yet run a ground to the engine block itself as you have told me that you do.
This dosen't make much sense does it?
Again Many Thanks.
Kerry
AnswerHello Again Kerry:
Turn the Coil/Magneto Over so the "this side out" is Not Out. If the Coil/Magneto Fires Properly with it Mounted this Way, then it is the Wrong Coil/Magneto. I had an Incident in the Shop a Few Weeks ago where we had the Same Problem. The Mechanic Turned the Coil Over and the Engine Fired. Apparently the Windings are Reversed on some of these Coils/Magnetos and if Mounted Wrong you get the Problem you Described. I Assisted the Mechanic for 4 Hours to Locate the Reason for have a Store Room with 6 Bad Coils. You are Describing the Same Problem we had. If you Hit a Snag or this Does Not Correct the Problem, I am Here if You Require More Assistance. Hope this Helps. Let me Know What Happens, Please. May the All Mighty Bless You and Yours. Thanks.
Good Luck
Respectfully
John
PS: I am Allowed to Answer 10 Questions a Day. If you See I am Maxxed Out, then Try Submitting your Question at or Just After 8pm EST (US). My New Day Starts then. Thanks.
Respectfully
John
