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Hi, I have what I believe to be a 3.5hp Briggs & Stratton style engine, not sure on model as it was a supermarket branded mower. I have drained and filled with fresh fuel and oil, replaced spark plug and cleaned out carb with carb cleaner. I am getting no spark from the spark plug with a reading of 2.1k ohms when testing between the plug end and the body of the coil. I have also used the business card method to ensure correct spacing between the coil and flywheel. Is the coil in need of replacement?

Any advice or suggestions would be appreciated.

All engines have model numbers no matter where they are purchased from. That being said all we can give is general help without model number. Kill wire connected to coil needs to be disconnected to test if the safety switches are the problem or the coil.

Thanks, I will check later and see if there is a model/serial number anywhere. I can confirm that I removed the coil + spark plug and the kill switch wire before testing.

Kill wire to be removed for spark testing.

Yes I've removed the kill wire, grounded the tip of the spark plug spinning the flywheel by hand and still no spark. I am pretty sure it's the coil but thought I may have missed something. I know the resistance measurement of 2.1k ohms was just below what is said to be acceptable which I believe is 2.5-5k ohms. But I'm guessing this varies depending on which coil and motor ect... I know very little about lawn mowers and have only been doing some research the last couple of days.

Does your coil have a metal spark plug cap?

If it does then pull it off (its a press fit connector and might take some force but don't try and pull the terminal off which its connected too) and connect the other end to the plug which is a tight fit and try and start.

Briggs don't give out ohms readings and only give a simple spark or no spark.

You should also be using a spark tester which loads the coil as if its under load from the engine.

This is a pic of the coil. Do you mean pull off the rubber angled plug to expose the metal terminal inside and then connect spark plug and try? I know I should be using a spark plug tester but this is only a cheap lawn mower and not worth wasting too much money just to diagnose problem. I have already changed the cheapest items i.e oil, fuel, spark plug. Will be better off buying a new/used one. Was just hoping this might be a quick fix.

No dont pull it off as its not got a metal cap.
Model,type and code off engine would help.

Its very unusual for a coil to fail and a spark tester would diagnose easier.

I've looked over the engine and can't see any ID plate/model or serial number anywhere. Here is a pic of the mower.

Is this what you're talking about?

Its not a briggs and stratton but a chinese sourced engine.
You are going to struggle to get a coil even if its not producing spark.
Might be better buying a new mower.

Will have to remove engine cover to find it. It will be stamped or etched on the part I circled or almost anywhere.

Ah ok never mind, thought it was worth a shot. I think I'd rather look for a decent second hand mower than waste anymore money on this. Thanks for all the info and advice 

I suppose the best one to look out for is one with readily accessible parts. ��

Carl_1 said:

Ah ok never mind, thought it was worth a shot. I think I'd rather look for a decent second hand mower than waste anymore money on this. Thanks for all the info and advice 

I suppose the best one to look out for is one with readily accessible parts. ?

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All the easy profit is in selling a complete engine.
The big cost is maintaining a parts supply with big overheads and low turnovers.
Good news is that the mounting points are usually the same so any newer Briggs will go in.
I have this problem on a daily basis and sme time ago stopped even trying to find parts for cheap imported engines.
Customer keep o telling me "they said Honda parts will fit it "
and now my reply is the same, " go back to the store and ask them to get the Honda parts for you"

If you bought it from a big deparment store & it is fairly new make up a big sign, put it on the mower then sit in front of the main entry door.
Ring the local news department before you do.
Chances the company will replace the mower or refund your money.

From now on whenever you consider buying a power product google the product name and the engine name.
If you draw a blank or find nothing then consider the tool as a single use throw away item.

Carl_1 said:

Hi, I have what I believe to be a 3.5hp Briggs & Stratton style engine, not sure on model as it was a supermarket branded mower. I have drained and filled with fresh fuel and oil, replaced spark plug and cleaned out carb with carb cleaner. I am getting no spark from the spark plug with a reading of 2.1k ohms when testing between the plug end and the body of the coil. I have also used the business card method to ensure correct spacing between the coil and flywheel. Is the coil in need of replacement?

Any advice or suggestions would be appreciated.

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At the back of the engine, you will see where the cable from the handle goes in. Remove that cover and ensure that there is no grease or dirt in that area. This is where the coil grounds out when you let go of the lever on the handle. If that is clean and clear of grease and dirt, then yes your coil is defective.