4hp Briggs problem.

cruhr1 · May 23, 2015

I have an early 60's 4hp Briggs all stock with the pulsajet carb that starts to pop and sputter at higher rpms. It has always run great with no issues up until about a month ago. It starts and idles fine and runs great up to a certain rpm. I thought it sounded like it was running out of fuel but I've cleaned that carb several times and it's got a new diaphragm and gaskets. I've tried setting the needle lean and rich and it still does it so now I don't think it's the carb.This engine does have the old breaker points ignition. I've set the points gap, the flywheel air gap and the flywheel key is not sheared. What do you guys think the cause could be? Is it the old points ignition going bad?

Thanks-Chad

joshua. c. · May 24, 2015

something in the ignition could be going bad but I don't know how to confirm that or how to find out which peace. I personally don't like maintaining points having to pull the flywheel every time they need cleaning. the non points ignition coil is a direct fit so why not buy one and eliminate the points all together?

cruhr1 · May 24, 2015

joshua. c. said:

That's what I plan on doing. I was just wondering if there is anything else I should be looking at that may cause this. I guess it is possible that there is still some sort of blockage in the carb. It runs so well at the low to mid rpm range that I don't think it's a valve problem. I guess I'll get the new ignition and probably check that carb again and see what happens.

jackeo21 · May 24, 2015

How hard is it to start? I put a '91 Magnetron (non-points) on my 5hp and it starts and runs well. When I was rebuilding it I put the points in, and they no longer worked :laugh: So I didn't even bother to fix them because I have coils all over the place :thumbsup:

4hp Briggs problem.

cruhr1

joshua. c.

Well-Known Member

cruhr1

jackeo21

Member