how can I tell what hydraulic set-up I have?.....all I can find on the tank is the serial no. which reads 54G843. In a parts book it for the nearest contender 78A series crawler it shows for 62G1>

Richard - 54G S/N prefix is a Model 141 or 143 Hyd Control .. and they can have one or two valves (typically just blade or blade and ripper).. or three valves (typically blade, ripper and tilt cylinder). The 141 has a smaller capacity hyd pump (17 gpm as against 29 gpm for the 143).

The 141 is used for blade and agricultural applications, the 143 can be used for these as well .. but the 143 is mostly only used, where a blade, ripper and tilt cylinder are fitted. All the systems look the same, use the same reservoir, and have either one or two valves in the tank .. however the third valve of the 141 or 143 is externally mounted.

Thanks Oz.....it's clear now

i have a parts book somewhere if you ever need anything
mine has only the one valve ,but i would like to make it in to a 2 valve
with the ports at the rear to use disc,s etc
you are making a grand job of that richard ,thanks for posting the pictures
cheers graham

"d4c24a" wrote:

i have a parts book somewhere if you ever need anything
mine has only the one valve ,but i would like to make it in to a 2 valve
with the ports at the rear to use disc,s etc
you are making a grand job of that richard ,thanks for posting the pictures
cheers graham

thanks Graham I got a P/B off e-bay which comes close....to be hon. whenever I speak to Chris in Moore's before i can find a page in the parts book he already has reeled the number off

Must say I have got a lot of satisfaction out of the job..... so far.

What I'm interested to know is how I'd go about putting a "Tee" in the line in order to run a seperate spool block for services on the back - for example a small tool-carrier.

The rollers are on a pallet ready for reconditioning up country later this week

richard that is what i would like to do ,if you do find out ,i would like to know
cheers graham

You need a change over valve, it has to operate two lines at once i will get you both some details.

Hi Richard, I once fitted a block of three auxiliary valves (with thier own relief valve as it is a higher pressure system) on a D4D, I took a line from the pump outlet across the dash panel and along the RH fender to the valve block, then the return hose along the same route back to the front of the hydraulic tank where the pump supply went in. The implement lines went out of the back of the cab to quick couplers on a bracket mounted above the drawbar.
This way you still restrict the blade to the original pressure but have a higher relief for the rear implements.
The main problem is, you will probably find the Cat hydraulic pump output flow too fast and if the pump is worn it may not be able to give enough pressure.
Try to make the bores of the new supply hoses and fittings as close in size to those in the Cat pressure line as possible and use a valve block big enough to take the flow, I think others have given these figures.
The system I fitted apparently gave these problems, but after fitting a new pump cartridge the customer used it quite successfully, albeit, a bit faster than ideal. I don't know if John Moore is still involved in the business, he may remember it as he was our Service Manager at the time and I was just finishing my apprenticeship, but it was over 40 years ago.

Catsilver, i learn something new every day....... i never knew john was a service manager.
Regards Gordon.

With many of this website's members being former Cat dealers, partsmen, service men, etc, that is one more reason why this has to be the best Cat website around. Thanks go to you all for sharing your expert advice with the rest of us through these past years.