I've diagnosed what I think is too much compression/ valve lash on briggs and stratton 9l902 0305 engine. I've searched you tube on how to adjust the valves but can only find videos on OHV engines. Am I missing something?
How to fix valve lash on a non OHV engine
- Thread starter Cory N
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cpurvis
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There is no valve adjustment on small flathead engines. That is taken care of when the engine is originally built (or the valves replaced) by grinding the end of the valve stem to obtain the correct clearance. It takes a pretty expensive piece of equipment to do that accurately.
bertsmobile1
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On side valves doing a valve lash adjustment is a big job.
You need to pull the head & carb off to access the valve chest then measure the gap carefully before you remove the valves
If the gap is too small you remove metal from the end on the valve, I use an oil stone for this.
Usually the exhaust valve will have closed down the gap
To fix this you have to grind down the valve seat.
It is very rare for the inlet to be out but when it is usually it will be too small from general wear so is an easy fix but the exhaust is a problem and best taken to a workshop.
Most will do it for about 1/2 hour labour.
You need to pull the head & carb off to access the valve chest then measure the gap carefully before you remove the valves
If the gap is too small you remove metal from the end on the valve, I use an oil stone for this.
Usually the exhaust valve will have closed down the gap
To fix this you have to grind down the valve seat.
It is very rare for the inlet to be out but when it is usually it will be too small from general wear so is an easy fix but the exhaust is a problem and best taken to a workshop.
Most will do it for about 1/2 hour labour.