Neil wrote:

Thanks Jim, it's been a long time since I was on a wheel tractor but I didn't recall ever seeing pressure controls for the remotes. I'm guessing there's some amount of standardization on remote pressure these days?

Hi Neil,
Most farm tractors (Wheel) these days have hydraulics in the 2500 PSI range with some outliers being a little more or a little less. The progression of hydraulics over the past 50 years has been phenomenal with larger gpm capacities and good cooling systems. I have an old M International with a factory hydraulic system that was for single acting cylinders and very low output and pressure.

Old wrote:

Might consider a hydraulic bowl conversion...

OM, thanks for the photos and the suggestion. Comparing the hydraulic bowl conversion with the original Cat 40 it appears the Cat engineers were going hydraulic but could not totally get the thought of cables out of their heads, hence the hybrid cable hydraulic 40 scraper! That bowl conversion makes sense. I had never seen one of those.

The conversion in OM's pics belonged to a contractor not far from here. I had a good look at it 10-12 years ago. It was quite nicely done. He had four of those No40's being pulled by case tractors building holding ponds on citrus farms.

OM, thanks for the tip on the Servicemen's Reference Book "Hydraulic Controls and Equipment". I got a copy yesterday and it has an entire section on the 40 scraper hydraulics and in particular how to align the lift cylinder when replacing. Lots of good info that I would not have been aware of except for your post.

Started on the lift cylinder project this week and found out the botched repair weld job was worse than expected. The flange is not only welded to the cylinder, the cylinder and flange are also welded in spots to the main scraper body. It is going to take a lot of grinding just to cut the welds to get it all off.
Cat was able to supply drawings for the cylinder assembly and parts so will still be able to rebuild like original. I debated on converting to the hydraulic arm but decided to leave it original but now I am not so sure that was the easy route to take.

Surface finish inside cylinder shows as a 16 but I thought that sounded a little rough. Different subject, does anyone know offhand what the surface finish of Jo blocks are?

all you need is just a hound finished for the new cylinder 16 ar is getting down there as a good finish. I bet if you most hydraulic guys they don't know what a surface finishes are. jo block that will ring and way lower but you would not want it anywhere near that they are cylinder.

Getting ready to get a machine shop to make the new mounting plate for the Cat 40 lift cylinder but Cat cannot find a detailed drawing of the mounting plate 5F6577. The assembly drawing 5F6586 has enough details for making the plate except for the thickness. The one on mine that some yahoo welded on is about 7/16 thick but it may be just a piece of scrap he had around when he tried to repair it.

Could someone measure the thickness of the mounting plate on a 40 scraper to find out what is correct? I am guessing it is probably 1/2" but that is a guess. Earlier pictures in this thread show the conglomeration welded up. As Glum said, the problem was the mounting plate and everything else appears to be usable with replacement piston parts .

Assembly drawing 5F6586 below

Thanks!

Looks like you saved me some searching! I wanted to have some new mounting made for mine as well. I believe I patched a missing chunk of it with 1/2'' flat plate. It sure would be nice if someone had a NOS tube laying around to buy, but doubtful. If you have your machine shop make extras, I would be interested in one or two...Thanks, JM

juiceman wrote:

Looks like you saved me some searching! I wanted to have some new mounting made for mine as well. I believe I patched a missing chunk of it with 1/2'' flat plate. It sure would be nice if someone had a NOS tube laying around to buy, but doubtful. If you have your machine shop make extras, I would be interested in one or two...Thanks, JM

The Fabricator will order enough 1/2" cold rolled plate to make two mounting plates, one for each of us. He recommended CR rather than HR as it is much easier for him to machine.
The tube would be a tough one to make with the tight tolerances and relatively thin wall. Thankfully I don't have to have that made (yet). My guess is that when Cat made the original tubes they had a special reamer that precise dimension as I don't think they could bore that thin wall tube that accurate. In the meantime maybe Cat can magically find the drawing.