[AT] tractor hydraulic pressure measuring? Dean

[Steve W.]

Cecil R Bearden wrote:
> The early tractor's relief valve was replaced with the later relief 
> valve with no problems.  I cannot find a reference to the pressure of 
> the to-35 pressure, but the MF-35 was 2800 .  The valve was usually 
> referred to 2750.  This seems to be correct in my memory of working on 
> the early Ferguson and fords.   I spent a lot of hours in a tractor shop 
> working on the hydraulics.   I would suggest looking to see if you have 
> a control valve that has another relief in it that could be allowing the 
> oil to bypass the control and go back to sump when you load it above 
> 1750 psi.
> 
> Early loaders had about a 2 in diameter piston in the cylinder and the 
> cylinder operated at a 45 deg angle usually.   If you work on the 300 
> psi difference, and take the area of the piston, it figures out to 1884 
> lbs of thrust combined.  At a 45 degree angle, this would be the cosine 
> of 45 (.707) x 1884 = 1331 lbs to raise a load.  This is about 1/2 yd of 
> sand, and that is about what the old tractors would handle.    It sounds 
> ok to me......   A large round bale or hay would be nearly flatten the 
> early tires. The rear tires would have to be ballasted and then put a 
> box blade on the rear also.
> 
> I am sure someone will try to  shoot holes in my figures, but it is a 
> close approximation.
> Cecil in OKla
> 
> 

Sounds about right. I'm just wondering if this is the tractors system. 
John says his tractor has a "front mount pump" The 35 I have has an 
internal pump for the hydraulics.

I've seen more than a few broken axles/spindles and front castings from 
heavy loads on these tractors. They are a handy tractor but loaders are 
not really fun on them. Especially the ones that don't have power steering !


-- 
Steve W.