Vave lash qun...

Ford had a tower intake manifold adapter so you could run the engine with the valley exposed. Good luck finding one of them.

Meanwhile back at the farm, if a tolerance calls for 0.014-0.018 clearance I just split the difference and set them at 0.015-0.016 and call it a day. Hasn't let me down yet.
 
The KRW lifteruppers were just for locating valve train noise and misbehaviors.
They were NOT intended for adjustment because no Fords had any provision for any sort of adjustment that could be done on an assembled engine.
The intent was that the mushroom stem valves were set by length* at factory assembly assembly and reset only as part of teardown and valve job in service. The idea, supported by mushroom stems and later by hardened seats, was that the valves would not need adjustment until the engine needed major work anyway. I do believe it worked...flathead valves in normal service don't need adjustment in use. Obviously the factory numbers were based on engineering calculations and measurements of what would be right hot.

*(I think the factory procedure was that the seat-to-lifter depth of a finished block was measured with special micrometer and the dimension scribbled on the block surface. Then pre-measured valve assemblies were dropped in to suit. This is essentially what would have been done in a professional garage valve job, too, measure the depth with special cone-seated micrometer, grind stems in the refacing machine. Welding or brazing lifter and cutting its top in same machine for loose assemblies, or hot rod cams.)
 
Walt Dupont--Me. said:
If you set them 10-12 cold they would be 8-10 hot. SO, set them 12-14 cold and forget about it. Walt
Click to expand...

Correct me if I'm wrong but this seems backwards.

Sorry to bring up an old thread but I'm trying to set my valve lash and it calls for 10-12 hot. Does anyone have a idea how much they expand. I know on my ohv with iron block and heads it's 4-6
 
As the valve and lifter expand it is going to decrease the clearance. No idea what the real number is, but using the same numbers posted in this thread if the clearance was set at .010 on the intake cold and hot it expanded .002 the clearance would now be .008. As the valve and lifter expand the clearance decreases.

On an OHV engine it is a totally different thing. You have a lifter, a push rod, a rocker arm and then a valve stem. All of these components are going to expand and it is going to be more expansion than just a lifter and a valve stem in a flathead. OHV procedures are not going to transfer well to flatheads in the valve train area.

"Sorry to bring up an old thread but I'm trying to set my valve lash and it calls for 10-12 hot."

Now why would anyone provide flathead cam numbers in Hot vs Cold? Where is the cam from and why hot valve lash number??
 
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JSeery said:
As the valve and lifter expand it is going to decrease the clearance. No idea what the real number is, but using the same numbers posted in this thread if the clearance was set at .010 on the intake cold and hot it expanded .002 the clearance would now be .008. As the valve and lifter expand the clearance decreases.

On an OHV engine it is a totally different thing. You have a lifter, a push rod, a rocker arm and then a valve stem. All of these components are going to expand and it is going to be more expansion than just a lifter and a valve stem in a flathead. OHV procedures are going to transfer well to flatheads in the valve train area.

"Sorry to bring up an old thread but I'm trying to set my valve lash and it calls for 10-12 hot."

Now why would anyone provide flathead cam numbers in Hot vs Cold? Where is the cam from and why hot valve lash number??
Click to expand...

I might be picking pepper out of knat **** but the cam also increases 3 dimensionally with temperature. Wonder if Farmer John knew about pepper in knat **** back in the 40's?
 
If it is that important to know the hot setting here is a possible approach. Set them a bit loose or even the 12 - 14 will work. Take the car for a good ride to eat everything up. It will stay hot for a while now. Pull the intke and check the valve clearance for one cylinder or maybe two. Compare with the original settings. If you set them at 12 and you measure 10 you will need 14 toy get 12 hot. You have now determined the expansion characteristics for YOUR engine. And now you will have a corresponding cold setting to get the hot one you want. A little loose might be noisy but too tight will not let the valve seat and cool sufficiently. That is where you definitely do not want to venture into.
Just wondering if anyone ever tried to adapt hydraulic lifters to a flathead. Would be a ton of work but we're noted for stupid stuff like that.
 
I am in the process of overhauling my 59ab and am setting valve lash this morning. I have been working from the small ford company engine service manual. It's the one with the orange cover. 'Stock' engine, stock cam, nos 8ba valves and guides without rotators, adj lifters. The chart in the back of this ford manual states that valve clearance for 59 ab intake is .010-.012 and exhaust is .014-.016. As I install each valve I have been setting them at .010 and .014 because That's within factory specs and I like them quiet. While everything is open and accessible, should I open them up a bit like .011 and .015 just to be safe? All work shown in this book is being done on an engine stand or work bench so we know the settings are for 'cold'. Maybe I'm picking pepper, but hey, why not at this 'easy to change stage'.
 

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GB SISSON said:
The chart in the back of this ford manual states that valve clearance for 59 ab intake is .010-.012 and exhaust is .014-.016. As I install each valve I have been setting them at .010 and .014 because That's within factory specs and I like them quiet. While everything is open and accessible, should I open them up a bit like .011 and .015 just to be safe?
Click to expand...

I would set them tight like you have (or are going to have). .010 & .014, they are going to get looser over time.
 
It might be fun to take a spare or used valve and measure it accurately and then heat it with a torch and re-measure and give the answer here for the rest of us.
 
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