A couple of years ago I overhauled the pump and motor on the steering on a D9R serial no 7tl. all went fine for about 2000hrs and the pump broke up by spliting the spline out of the cylinder block. Rebuilt the pump again bench test fine. When setting it up on the dozer the pump pressure modulates quite a lot when stalling out with brakes on.. Steer works fine with good pressure and charge pressure. Checked another D9 and found that the pump pressure does the same thing. I suspect that the cutoff spool is worn (40000hrs) but very hard to isolate because of the multiple paths the oil takes in the control valve. Cat have no parts and no new control valve available in the system. Has any one come across this issue or where I can get parts because I suspect this is the reason the cylinder block split. Regards Mike
I can’t answer your question as I’m no fitter,but locating parts for that tractor are harder to find than people suppose. There’s one thing finding them,but another thing actually purchasing them. By the sounds of it,you’re finding that out for yourself unfortunately
I know there are less and less guys that actually care anymore, but did any of you that got to run new N or R model tractors ever dream that before these tractors were 30 years old they'd be considered obsolete? That Caterpillar would dare to go against the principles it had been founded on?
I drove D10N,R, D11N,R but that was in 2001 and those machines at Syncrude Fort McMurray would all be in the bone yard a long time ago. They were getting more than 6000Hours per year as they run 24/7 every day of the year pretty much, and for people who don't believe it needed complete undercarraige every 600- 900 hours including all rollers and tracks. Caterpillar made Billions up there. Tar-Sand eats steel like no other place on earth from what we were told. Grains are extremely jagged and eat rollers, pads and rails, sprockets. Finnings shop up there has over 150 mechanics on 7 days a week. Simon C
I worked at a shop that did chromium carbide overlay on pipe used to pump the oil sands slurry. Probably 95% of their work was for Syncrude and they were very busy because so many replacement pipes were required. If I recall the overlayed pipe lasted 4 or 5 weeks. Straight sections could be rotated to get longer life. Elbows were changed more often. Standard pipe wasn't economical because it would have to be changed far too often. The oilsands are also soft ground and all the shovels require special extra wide pads to prevent them from sinking and getting stuck.
Good post. It’s actually easier to get parts for D8H than D9R
Thanks Guys. Have put a tech enquirery into Cat to see what comes back. nothing yet.
They’ll be in no hurry to get back to you. Probably won’t respond at all unless you poke them