Bill Jewell

Need Help on Adjusting Valves on 1930 Franklin

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Hello,

 

I am attempting to adjust the valves on my 1930 Franklin and have run into an issue that I have not seen before.  I adusted the valves for cylinders 1, 4, and 2.  When I got to cylinder 6 I am finding that i cannot get the gap to open for the exhaust valve.  The "rocker arm" / walking beam will not lift off of the top of the valve no matter how much I turn the screw.  I hand cranked the engine a few times and I am seeing the exhaust valve open and close.  Am I doing something wrong or is there a problem with the valve or walking beam?

 

Thanks for any help or advise!

 

Have a Great Thanksgiving!

 

Bill Jewell

Arlington, Texas

 

(cell) 817-739-8565

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Are you sure you have the piston at the top on a compression stroke? Not sure about Franklins but this is how most tappet clearances are set. From my manual the clearance should be .007 warm.

See attached for some general information.

 

1930 Franklin (Models 145 +147).pdf

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Hi Bill - 

 

Check to see if the pushrod is free when you unscrew the adjsuter.  You can even take the adjuster all the way out. The pushrod should spin freely with the valve closed (follow the book procedure of adjusting #6 valves when #1 exhaust valve just closes)

 

If the pushrod is hitting the rocker and is not free, then it could be that the valve cage was installed without checking this. Was the engine recently assembled?

 

If this is the problem, you can raise the valve cage with shims on top of the stud pads on teh cylinder head. The pads should already be about 1/16" above the cylinder head surface. Sometimes things are changed around and the valve cage no longer sits up where it should. Remember - if you change the position of the valve cage at all, you'll need to readjust the pushrod tube lengths. 

 

 It's also possible that the pushrod is too long. Is it an original pushrod?  You can also shorten the pushrod, but you need a good tip grinder to do a nice, square job and if you grind too far, you might grind through the case hardening on the tip.  You would not need to take off much, so you could grind a bit from each end.

 

It is better that the pushrods not be too short, so only take off what is needed and/or only shim the valve cage box up enough to get your clearance.  

 

If this is not the problem - let me know and I can help zero in on it. 

 

Tom Rasmussen

763-786-1518

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