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5th valve modification advice requested

Postby roweenie » Sun Apr 14, 2019 6:01 pm

I'm currently revisiting an older 5th valve addition, and I'd like to get the TNFJs opinion on a few ways I might go - - -

First, some facts:

1 - the valve is a top loader, and all parts are easily removed for service while attached to the horn.

2 - the horn plays equally well as a 4 valve or 5 valve instrument

3 - the set up is currently detachable, but it is an IMMENSE hassle to get it out as presently configured (the valve needs to be removed from its casing to get the assembly out, and even then it's a hassle to remove)

4 - this horn will never leave my possession (barring an unforseen catastrophe)

So, with that in mind, should I:

a) reconfigure the tubing so it is easier to remove (even then, I will still need to remove the valve from it's casing to extricate the assembly)

b) attach it permanently (this will also likely require re-routing, so I have easier access to the bottom 1st valve cap)

c) leave it alone as it is

Note - although the valve is serviceable in place, removal makes it easier to get to the #1 bottom piston cap, and also easier to clean and service the tuning slide.

Sometimes, I'm just a little too close to the job to decide what the best course of action is :oops:
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Re: 5th valve modification advice requested

Postby Ken Herrick » Sun Apr 14, 2019 6:51 pm

It's hard to offer any comment without seeing what you have now other than, if it works don't fix it.
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Re: 5th valve modification advice requested

Postby the elephant » Mon Apr 15, 2019 2:18 am

Pics…?
Image

For all you do, this " target="_blank's for you.
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Re: 5th valve modification advice requested

Postby roweenie » Mon Apr 15, 2019 8:41 am

Sorry I didn't include pictures - - - I was thinking my question was more "philosophical" (opinions and advice) than practical.......

I will take some this morning and post them.
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Re: 5th valve modification advice requested

Postby iiipopes » Mon Apr 15, 2019 11:33 am

With all due respect, in most contexts, opinions and advice are based on experience rather than theory.
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Re: 5th valve modification advice requested

Postby roweenie » Mon Apr 15, 2019 2:19 pm

Well, I was looking at it today, and I've determined how I can modify the 5th valve assembly without a complete rebuild.

Image

The problem was clearing the valve spindle (next to the 4th valve knuckle) and the bottom crook (next to the large branch) simultaneously. So, I took about 1/8" off of each end of that bottom crook, and now both clear their obstacles (it's very close, but it works). I still need to remove the stop arm to make it work, but that's much better than having to remove the entire valve cylinder first.

An old timer who taught me a lot about engine rebuilding told me once, "ten thousandths of an inch clearance between parts (in a motor) might as well be a mile".

Image

Image

Image
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Re: 5th valve modification advice requested

Postby YORK-aholic » Tue Apr 16, 2019 11:23 pm

roweenie wrote:An old timer who taught me a lot about engine rebuilding told me once, "ten thousandths of an inch clearance between parts (in a motor) might as well be a mile".

Image


Yeah, could you imagine boring out the cylinder bores .010" but using standard sized pistons? How long would that motor last? :shock:

Are those York bottom valve caps?
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Re: 5th valve modification advice requested

Postby roweenie » Tue Apr 16, 2019 11:59 pm

YORK-aholic wrote:
roweenie wrote:An old timer who taught me a lot about engine rebuilding told me once, "ten thousandths of an inch clearance between parts (in a motor) might as well be a mile".

Image


Yeah, could you imagine boring out the cylinder bores .010" but using standard sized pistons? How long would that motor last? :shock:

Are those York bottom valve caps?


Ok, so I guess I need to be a little more specific - I was talking about the clearance between a connecting rod and the oil pan on a 1924 Ford, NOT the clearance of a piston inside its cylinder (and IIRC it was probably closer to .020).

And yes, they are original York caps.
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Re: 5th valve modification advice requested

Postby roweenie » Wed Apr 17, 2019 12:33 am

iiipopes wrote:With all due respect, in most contexts, opinions and advice are based on experience rather than theory.


True, but I probably should have more clear that the gist of my question was to ask if it was worth the trouble to keep it detachable, when servicing the valve while in place was doable. :oops:
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