[AT] 430V

Wed Sep 13 08:03:34 PDT 2017

I think one reason "rocking" a wheel sometimes works is that you are
working both directions. Ever have a tooth pulled? The dentist doesn't just
place a steady pull on a tooth and pull until your jaw pulls out of your
mouth (even though it may feel that way). He grabs the tooth and yanks it
one way and back the other. Back and forth. The travel of the wheel made up
of all of the minor play in all of those gears allows a small amount of
impact first one way then the other.
My point being that I think it is a mistake to keep trying to force the
piston in only one direction. In the case of Steve's wedges for example it
would be nice to be able to reverse that force and maybe move the piston
back a smite (technical term  :-)  ) even if it was only a near microscopic
amount. One factor to consider I would think is that I think that the push
Steve is showing would maybe be less likely to cause any damage than
pulling it back might cause. More strength in compression than in tension?
Of course trading a stuck piston for a block crack isn't much of an
improvement so use a lot of discretion. I'm sure you will...

Steve... Am I thinking right that when rocking one wheel  you lose half of
the force advantage because of the differential gearing and the other wheel
being stationary?

Our dog and I have been discussing the possibility of multiple universes
this morning and my head was hurting already. She has some interesting
thought on the matter but I still think she is wrong...
:-)

.

On Wed, Sep 13, 2017 at 8:08 AM, Stephen Offiler <soffiler at gmail.com> wrote:

> Hi Spencer:
>
> Getting back to the point where the discussion brushed on the
> toggle/knuckle press analogy.  See attached sketch.  When almost at TDC, a
> force applied at the toggle "hinge" (crank pin represents the hinge) is
> multiplied on each of the "arms" (con rod and crank throw represent the
> arms).  On the tractor, when you apply force to the rear axle with
> transmission in 5th, this force tries to spin the crank, creating a
> torque.  Relation between this torque and the force at the toggle hinge is
> shown in the sketch.  How big is this force, I asked myself.
>
> I looked up the bore and stroke numbers:  4.25" x 4.00" so the crank throw
> is 2" which is .167 ft.  I made a couple quick assumptions about engine rpm
> and tractor ground speed in 5th and came up with roughly 30:1 reduction
> ratio thru the transmission.  That's the engine's advantage over the rear
> axle, so it is a disadvantage working backward.  If you could hang 100lb at
> 6' horizontally behind rear axle (say a 4x4 chained to the wheel) that's
> 600 ft-lb on the axle and with that ratio it works out to just 20 ft-lb on
> the crank.  With the 0.167 ft throw, that's a force (shown as big F in the
> sketch) of 120 lb.
>
> What I'd be trying to do is apply larger force at F.  I was thinking of
> maybe driving wooden wedges between the crank and the block.
>
> SO
>
>
>
> On Tue, Sep 12, 2017 at 11:44 PM, Spencer Yost <yostsw at atis.net> wrote:
>
> > Be glad to Mike.
> >
> > But first I want to mention some of the comments about patience. I've
> > never had a tractor that begs to be "snuck up on". This is clearly a
> > tractor that deserves to have a chance to be freed with the least amount
> of
> > tool marks, grease removal, and parts replacement. If I can get this
> > tractor running well without any disassembly or noticeable "technician
> > marks", this is it.  I feel certain, based on what I've seen, that I can
> > get this tractor freed and running. If it doesn't run to my satisfaction
> > then I will tear it down. But I think I can get it to run well without
> > tearing it apart.
> >
> > What I have tried:
> > 1: I shot it a couple of birds. This did not work
> > 2: I drink a couple beers and stared at it. This did not work.
> > 3: I soaked it for three months in a variety of different penetrating
> > fluids.
> > 4:: I raised one wheel, put it in fifth gear, and tried to apply force to
> > the raised wheel while the other wheel was  on the ground and chocked.
> This
> > did not work.
> > 5: I tried raising the entire rear of the tractor with chains on the rear
> > wheels and 5th gear.  Nothing.
> > 6:: I tried refrigerant. This seemed promising, but did not do anything
> in
> > the long run.
> > 7: I tried a hydraulic jack  on the counterweight of the crankshaft. But
> > the front end of the tractor is  the light and I feel sure I'm not
> putting
> > much pressure on it.
> > 8:  I have tried putting air pressure on the cylinder to try to drive the
> > penetrate down.
> > 9:  Rapping the piston with a brass bar during all of these
> >
> > To do:
> >
> > 1:  air pressure:  I am having still a little too much trouble with air
> > pressure leakage through the valves. So I am closing off the exhaust
> > manifold and the intake manifold with some bar stock and gasket material.
> > I have yet to finish this, as the exhaust flange was a real bear to get
> off
> > of the exhaust manifold. I just got that off tonight. Hopefully within a
> > day or three I will have that finished. Then I should be able to apply
> > plenty of pressure to the cylinder.
> > 2:  Create an opposing force for the hydraulic jack on the counter weight
> > on front cylinder. I will be fabricating a frame that  mount to the
> > cultivator bolts. This will allow the jack to push against something
> other
> > than gravity.  This should be easy, but I am cheap. Channel iron, anchors
> > and eye bolts are expensive.  So I'm trying to find something that I can
> > fabricate, or buy, that will allow me to inexpensively build some sort
> of a
> > frame or chain sling to mount the hydraulic jack on top of.  Still
> > researching this.
> > 3:  Additional hyper cooling. I may still try the dry ice and alcohol
> > method.
> > 4:  A penetrate that works on the aluminum oxide in the galvanic
> > corrosion. There are a few compounds that do this. I got one from Brice
> > Adams who got it from a chemist at the university he works at(methyl
> > salicylate). If I try any type of solution, this will be it. But it seems
> > like black magic. So I'm going to leave this for later.
> >
> > Things I have ruled out:
> >
> > 1: Pulling it. If I can't get it to free with methods I've tried,  I'll
> > just leave rubber on the road.
> > 2:  Rust removal solutions. I may try this yet, but the compounds I have
> > looked at I doubt will do anything, as I believe galvanic corrosion
> between
> > the aluminum and iron is my main problem.
> >
> > As usual, keep the ideas coming!
> >
> > Spencer Yost
> > > On Sep 12, 2017, at 5:41 PM, Mike M <meulenms at gmx.com> wrote:
> > >
> > > I've heard of the diet coke idea as well. To think I used to drink the
> > > stuff.
> > >
> > > Spencer, this has been a long thread, and your patience is incredible.
> > > Would it be possible to give a short summary of what's been tried so
> far?
> > >
> > > Mike M
> >
> >
> > _______________________________________________
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> >
>
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>

-- 
-- 

Francis Robinson
aka "farmer"
Central Indiana USA
robinson46176 at gmail.com