WD45 hydraulic pump

Before you take the pump off, adjust the linkage under fuel tank to raise the pump linkage up more. See if it increeses the pressure.

I bought all the stuff from Sandylake but in reality it probably just needs a good cleaning out. The slightest bit of FOD in there can mess things up. Same pump on the CA and there is no screen and to make matters worse it pulls from where the metal is. They have a rebuild kit with gaskets, balls, springs and the such.

Don't buy the rebuild kit. It has more parts you won't use than you will use.

Have a bucket and pan full of clean diesel fuel to rinse parts in and good clean area so if you drop a part you can find it.

Thanks for all the imput guys!!! I'm not the kind of person to jump into something half @ss , so I value all your info!! Ryan

I will forward the scans to you. Maybe you can post them here?

I can help post as well. Will be in need of more detailed info for the pump on my 45.

I'd say that keeping track of the position and direction of the sleeves and valves in the bore the plungers feed  would be the most important thing.They are not all the same but close enough to confuse you.Been too long since I was in there but it seems that one sleeve is different and it goes in front?Anyway,if you can take it apart carefully and note how it was,you should be alright.I have the luxury of an old AC service manual to help keep it straight.Difficult to not cut the o-rings on the unloader valve when pushing it past the inner passages. My 45 never did have good,consistent pressure.Replaced the springs and seats a couple times and even put a new unloader valve in but still no luck even with 11 shims in it.Even sent it to Bill at Sandy Lake a few years ago and still behaved the same.Not Bill's fault.He basically re-did all I had done years before other than fixing some worn internal linkage but still the same end result.I finally drilled the center of a flat washer and stuck it in there in place of the shims(even thicker)and now it's usable.Not perfect but better than it ever was.The odd thing is that it always did/does good at idle or just above but at part throttle or more it wants to "unload" before it fully extends the ram.The only thing I wonder about is the ball and seat after the unloader valve which has not been replaced.

Well, here you go, thanks to Chris/CT.  He emailed to me and I am posting them for you here.

Oh, well my theory is NG, somethings in life are never explained I guess!

i have a 1949 wd that is leaking prefusly out of the adjusting screw on the front side of the tractoe. any thoughts? also when i set the screws to the manuals recs for hold position ( i built a 3 point for this tractor and need to hold some implements a certain heights) it doesnt seem to change response ( all the way up or down). Any help would be appreciated!

I'm not sure a dealer service manual is going to be all that more informative than what is currently available. In the years those tractors/pumps were made, the service manual was adequate for most AC mechanic's to understand and service this part. They are not that complicated, no rocket science degree needed. maybe call MACK and pick his brain some, he might have some more technical lit to send you.