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Rick, Factory Authorized Trainer
Category: Small Engine
Satisfied Customers: 8063
Experience:  Outdoor Power Equipment technical trainer since 1990, covering eight states.
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I have a Briggs & Stratton 16.5 HP Engine for my riding lawnmower.

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I have a Briggs & Stratton 16.5 HP Engine for my riding lawnmower. Everytime I try to start it, it won't crank, It will crank one and stop. When I take the sparkplug out, The engine will crank as many times as possible. What is preventing the engine from cranking when the sparkplug is installed?
Should be an easy fix. Can you let me know the full model, type, and code number off the shroud please? I'm betting this is an overhead valve?
Customer: replied 6 years ago.

I'm not sure if I got the number right, the labels are fading after years of use.

Its a Briggs & Stratton 16.5 I/C OHV engine.

the number are as follows. I not sure which # is for Model # or Type or Code #.





let me know if this helps



Thank you. Let's try a valve adjustment first.and then let me know if you still have problems, but this fixes it in the majority of cases.

Intake - .003"/.005"
Exhaust - .005"/.007"

The setting should be done on a cold engine with the piston 1/4" past top dead center on the compression stroke.

Here's some additional information that shows the process in detail. Scroll down to the bottom of the page to where it talks about adjustments. It will link to some helpful pictures as well. If there's anything you're not clear on, please let me know.

Valve Info

Hope this is helpful!

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