Briggs Stratton valve problem

[JackT]

I have an 11 HP Briggs (flathead) and the intake valve spring retainer keeps popping off the valve stem. Doesn"t appear to be worn. Any ideas why this is happening?

 

[Anonymous-0]

Jack, go to bat auto technical on the www and scroll down and click on small engines. Under new topic type in your problem. There are some helpful
guys there that will probably have the answer.

 

[JDemaris]

There has to be wear somewhere. That thing probably has the keyhole type retainer. If won't work off unless the machined cut in the valve stem - or in the retainer is worn. The upper edge in the cut of the valve stem has to per a perfect 90 degrees with no wear. If you buy a new valve, it comes with the new retainer.

Now - if you DON'T have the keyhole retainer - that's a whole different story.

 

[JackT]

Yup, its a keyhole type retainer all right. After I pulled the valve out and looked closely I did see that its worn. Time for a new valve.

Thanks to both of you for your replies!

 

[Joe (Wa)]

I had the same thing happen on a 10 hp B&S engine exh valve on a portable gen. Power went out early evening, it would start but bucking every few seconds. Pulled the side cover and keeper was adrift and cocked under the valve spring.

Got it real clean with carb cleaner spray, put a couple drops of crazy glue on the retainer/bottom of the spring and pushed it back in place.

Run it for ~14 hours until power came back on next morning. Bought a new valve, spring, & keeper. That was 3 years ago, new parts still in the packages. Gen has run about 50 hrs since using it to run pumps, tools, etc waiting for it to happen again.

Bought a new gen with Honda engine for the dozen or so times a year that the power goes out in this area.

Joe