Its not that hard to do the valves on the L-head. The hardest part would be a valve guide replacement which it sound like you may need to do here; seldom need to replace valve seats and sometime they not even available. You just need access to the correct tools. These can be expensive for an one time repair job. In a shop setting they are not that bad; although, it can be a rough on small start-up operating on shoe string budget. I have doing this for 6 years and only do a valve job less ten times a year.
The reason I think you probably needing the replace a valve and guide which is most likely the exhaust valve is the carbon build up that you just partially clean off the valve stem. This is usually caused by blow by of a worn valve stem and guide.
The valve spring retainer should be a self locking key hole type. These are much easier to remove then the split type or the pin type.
If you decide to do the repair download a copy the Briggs 270962 Single L-Head service manual. The instructions for doing valves is in Section 6 (Compression).
Last edited by AVB; 03/10/15 08:01 AM.
