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Adjusting valve clearance

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I've got a Briggs Model # 326431 and I may need to adjust the valve clearances on it. There was some excellent advice on this subject earlier on this board, but I am wondering if someone could explain this further to me. I'm a self professed novice, so it might have to be explained to me like I am a 3 year old. Thanks!

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You will first need to locate the crankcase breather plate, since the valve adjustment area is behind that. Follow the breather hose from the carb to the plate. On most single cylinder B/S engines you will need to remove the carb since the plate is behind it. Once you remove the freather assembly from the engine, you will be able to see the valve stems (with the valve springs mounted on them, and the camshaft followers which meet with the valve stems in that cavity. You will need a set of feeler gauges that go up to at least .020 in .001 increments. Next you will need to make sure the follower is sitting on the base circle of the cam and not the lobe when you do the measurement. To do this watch a valve and rotate the engine, you will eventually see the valve moving upward and compressing the spring. Rotate the engine till the valve is completely down (closed) then rotate it at least another 90 degrees to make sure it is completely down. At this point you can use the feeler gauges to measure the valve clearance. If it is insufficient, use a screwdriver to pry the valve upward and insert a file between the valve stem and follower. Use it to remove a little material. Then re-check the clearance. Don't remove too much. I think the numbers should be .009 on the intake valve and .018 on the exhaust valve. You can tell which valve is which by checking whether the valve lines up with the intake or exhaust on the block. It is easier if you have the head removed. The exhaust valve is usually smaller and you will see that it has been much hotter. You do not have to remove the head, but be sure which is which since the clearances are different. Hope this helps. If this is not understandable, then maybe some others can explain it more clearly.

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