OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Engines Questions On Briggs & Stratton Engines Qantum Priming query

I have a key start Rover Mower with a Qantum 6HP Motorola on it. If you use the pull start it starts easily. It seems that using the electric start doesn't quite spin it as quickly. The battery is fully charged and as such my thoughts are around the primer, carby is clean and I've tried two primer plate gaskets as we'll.
Any thoughts?

Hi Andrew,
These are my thoughts after reading your symptoms.
Sounds to me like your battery is failing under load.

I'm not familiar with your machine.
But, you say it is starting easily with the manual starter, so you can eliminate the primer being at fault.
Sounds like your starter motor is OK, as it is turning your engine over.

A fully charged battery is no indication of how it will perform whilst doing its designed task.
The only true way to test any battery, is to measure its terminal voltage under load.
Do you have a multimeter?
Cheers

I agree with Mark, if it feels normal and starts normally when you pull the recoil starter, failing to crank properly or to start when you use the electric starter is a problem in the electric starting system. It has nothing to do with the carburetor or fuel system.

There are both mechanical and electrical things that can go wrong with the electric starter. As Mark said, you always begin by checking the voltage - right at the starter motor as well as at the battery.

Hi Andrew,
I agree with the other posts. One thing I have come across, if by chance your quantum is ohv ( which normally they are not) on ohv Briggs the spark plug gap is vital for easy starting. I had several 6hp ohv engines on Stiga compact ride-ons , which would not start with the key but with the rope. After many hours of stuffing around it came down to a 20 thou gap on the spark plug (which is in the workshop manual) solved the problem.