Re: Hydraulic pump Failed **ALL FORETRAVEL OWNERS SHOULD READ**
Reply #243 –
For those members who decide to remove and replace their own hydraulic pump at home (rather than have it done by a "pro" shop), I found a good tip online to help with pulley removal.
The first photo in Justin's post (above) shows the process of removing the pulley. This is exactly the same type pulley that I found on my coach. The way you are supposed to remove the pulley is first you remove the 4 bolts from the pulley hub. Then you take 2 of the bolts and screw them into the two "extra" (threaded) holes in the hub. The bolts are supposed to thread into the holes until they bottom out, at which time additional torque evenly applied to the bolts will relieve the clamping force on the split hub and allow it to slip off the shaft. As shown in the photo a little "help" with a large screwdriver might be required to loosen the hub. Link below to my pump rebuild thread that contains some photos of my disassembled pump pulley.
Vickers V10 Hydraulic Pump Rebuild
The problem with this removal method will arise if the threaded holes on the hub are very dirty and full of crap. When you try to screw the bolts into the holes, you will encounter a lot of resistance from the dirty threads. In really bad cases, the bolts may bind up and never get in far enough to bottom out, and the split hub will not separate for removal.
The answer in this case is to use a thread cleaning tap or a thread chaser to clean out the threaded holes before you try to insert the bolts. I happened to have a nice set of Craftsman thread cleaning taps that I inherited from my father, and it contained the proper size tap to use on my pump pulley. Don't ask me what thread size it was - that was 9 years ago and I don't remember. If you decide to use this tip, you will need to remove one of the pulley mounting bolts and check the thread with a gauge to determine the correct size. Lowes, Home Depot and Ace Hardware usually have a handy thread gauge in the "nuts & bolts" department.
Thread cleaning taps look much like regular thread cutting taps, but with subtle differences. First, they don't remove any metal - they just straighten the threads and remove dirt and trash. Second, they usually have squared off tips so they can clean all the way to the bottom of the threaded hole. See first photo below.
Thread chasers are a bit different shape, but they accomplish the same purpose. See second photo below.