What makes engine get spark?

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, and others.

PHillary

Active Member
Messages
33
Location
Lakeland, Florida
I have a 23-26cc engine in a Redcat Baja Truggy I have been trying to get started for a friend....the motor turns over fine and gas is getting into the cylinder but the spark seems faint or non existent at times....could it be that the coil wire itself is bad or is not receiving charge to start the motor.....correct me if I am wrong but wouldn't the charge for the ignition come from the battery box somewhere to the ignition coil or does the pull start itself give power to the spark plug on these type of engines? Thanks in advance for any help.
 
It works when the magneto rotates around on the magnet that creates it own charge ,like a generator!

Make sure that the magnets are clean of rust ,an the coil fingers are clean & adjusted close to the magneto magnets ,
I set mine by a piece of paper width!

Could be a weak coil as well!
 
Well, when you turn over the engine, the flywheel rotates on the crankshaft, and that flywheel has a magnet on it, so when your pulling the pull start, the magnet passes under the ignition coil and that makes spark and sends it through the coil wire, into the plug, into the engine. This is the coil
kmkg320-10.jpg

This is the flywheel
rv670171.jpg
s-l300 (1).jpg
Those fins are for cooling,if 1 gets broken off, it will become unbalanced and the cooling will be compromised.
In short I think your coil is bad
 
okay for starters instead of buying a new ignition coil...take apart engine in that area and clean coil leads and starter magnets then put back together and see if I get spark if not coil wire and/or flywheel will need replacing...correct?
 
okay for starters instead of buying a new ignition coil...take apart engine in that area and clean coil leads and starter magnets then put back together and see if I get spark if not coil wire and/or flywheel will need replacing...correct?
Try cleaning the coils pick up and the flywheel magnet, if that doesn't work, get a whole new coil asembly, the magnet in the flywheel doesn't really go out often so I'd do a new coil first and if that's not it then go for the flywheel.
And coils are real cheap
 
Last edited:
Try cleaning the coils pick up and the flywheel magnet, if that doesn't work, get a whole new coil asembly, if the magnet is still strong (you'll be able to feel it) its fine. And coils are real cheap

LOL ,he can feel it by holding on to the coil wire as he pulls the rope!
 
Also ,make sure your kill switch isn't grounding out ,an the plug wire isn't damaged or fraid!
Those coils are common in all small engines ,like weed eaters ,small hand held leaf blowers ,some interchange with
each other ,so if the coil is bad ,an you have an old broken down piece of equipment laying around ,also your local
small engine shop should have one!
 
Last edited:
Check the gap between the Coil and the Flywheel first . The gap could be to big which would make the spark potentially weak .
@1Coopgt is onto something ? should be a gap the thickness as business card between the coil and flywheel? any bigger and the spark will be too weak? and if its too close the coil and flywheel grind/could touch ?
 
Thanks guys...still haven't taken the motor out of the car yet....a little nervous as I have never done a large scale rc...I keep telling myself it is not much different than a nitro but I know that's not true....I will probably tackle this on friday night into Saturday morning as on the weekdays/nights I am just too tired to deal. Thanks for all of the tips so far.
 
Thanks guys...still haven't taken the motor out of the car yet....a little nervous as I have never done a large scale rc...I keep telling myself it is not much different than a nitro but I know that's not true....I will probably tackle this on friday night into Saturday morning as on the weekdays/nights I am just too tired to deal. Thanks for all of the tips so far.

This is for your safety ,DO NOT try to start the engine out of the car with exposed clutch shoes ,or the shoes not
being covered!.....(y)
 
This is for your safety ,DO NOT try to start the engine out of the car with exposed clutch shoes ,or the shoes not
being covered!.....(y)
Damn it quoted the wrong person.
Thanks guys...still haven't taken the motor out of the car yet....a little nervous as I have never done a large scale rc...I keep telling myself it is not much different than a nitro but I know that's not true....I will probably tackle this on friday night into Saturday morning as on the weekdays/nights I am just too tired to deal. Thanks for all of the tips so far.

You don't need to take the motor out to check the Coil gap. Just remove all the screws holding the fan cover/pullstart on.
 
@1Coopgt its tight in a dbxl to get at them even with the pipe off. Its 5 bolts (4 if you don't have the engine cage front left bolt in) and 2 fuel lines and the carb linkage. The engine practically falls out. Never tried to take the pull start off in frame so I cant comment on how it would go.
Just a thought.
 

Attachments

  • 20190620_220307.jpg
    20190620_220307.jpg
    113 KB · Views: 3
  • 20190620_220414.jpg
    20190620_220414.jpg
    178.8 KB · Views: 3
@1Coopgt its tight in a dbxl to get at them even with the pipe off. Its 5 bolts (4 if you don't have the engine cage front left bolt in) and 2 fuel lines and the carb linkage. The engine practically falls out. Never tried to take the pull start off in frame so I cant comment on how it would go.
Just a thought.

Oops I forgot . I was thinking HPI 5B.
 
Back
Top
AdBlock Detected

We get it, advertisements are annoying!

Sure, ad-blocking software does a great job at blocking ads, but it also blocks useful features of our website. For the best site experience please disable your AdBlocker.

I've Disabled AdBlock    No Thanks