I know there's lots of experts here that will be able to help me. I know Bob/Ont from another forum but I don't have his current e-mail. He's helped me a lot in the past but I see there's lots of Cat experts here. If you have welding questions I can probably help you out. A little bit about my background, I'm an Alberta red seal journeyman welder and also have my B-pressure ticket. Currently I work as the technical product support specialist (welding) for a large industrial supplier and provide support to over 170 branches across Canada. Now for the questions regarding my 1986 931B ser. 25Y1916. I had the steering clutches rebuilt and also had new brake brands installed. They are dry clutches. Cost was beyond astronomical in case your wondering, $6000+! Steering valves were rebuilt but the clutches still weren't working properly so I had to do a tear down to get them out. I have no way to check for internal leaks on the short steel lines going to the slave cylinders because I have a backhoe and all the hoses have to be hooked together before I can start the machine. I'm guessing the only way to check is through the cover for the brake adjuster? I don't think they leaked before so hopefully they'll be OK. One side had signs of oil in but also lots of signs of water at one point. I had a hydraulic line for the backhoe blow that went right over the cover and I think that's where the oil came from. The other questions I have are regarding the small internal spring on the brake linkage. It hooks up on a tab welded to the front of the clutch compartment. I noticed online that some manuals don't show this spring. Is it an update and what is its purpose? I bought new springs and it says to adjust them to 6.6" when installed. I put them in the 3rd hole and they are close to this measurement but may be slightly short. There is a slight tension on them. Should this be good enough? Thanks in advance! Oh, I have a tip for anyone doing steering clutches on a similar type machine. To make it easier to lift the clutches (tanks in place) lift them using a strap on the ends of the brake band with all the hardware off. It lifts them more level and the strap doesn't get caught up in the bottom when you need to pull it out.
Hello Welder Dave, the sprind is to keep the fork in place with the anchor assem. , the small plug on the outside of the case can be used to get some air out of the system, if its leaking then the line inside small line may not be seated right. the spring was there when it came out , and the hole should be ok. the adjustment on the clutch and brake is very important, make sure that the lobe starts to move as soon as you put preasure on the pedal, and the brake starts after the pedal is about half. good luck,sam.
The small plug on the outside of the case where the slave cylinders are bolted to is the place to poke in a pressure gauge, activate the clutch and see what pressure you have, then release the clutch activation and see the pressure come off, a 600 psi clock will do. tctractors
Thanks for the responses! How important is that spring? I kind of figured it was hold to everything in place when the brakes weren't activated but I see some machines don't even have it listed in the parts diagram. I had slight pressure on it but from using a ratchet and extension to tighten the slave cylinder in place, somehow pushing the spring out of the way a little stretched it and now it has no tension. It never fails, when you think you're making progress something odd like this happens. LoL I hate to take the slave cylinder back out since I brushed sticky aviation form-a gasket on it to seal it. I'm thinking maybe I can just bend the bracket on the linkage down a bit to put a little tension on the spring. Either that or try to bend the spring tighter but I don't want to break it. It's a new cat spring and I'm puzzled how it could stretch so easy when it was hard to stretch to put on? As far as the internal hyd. lines leaking, I think it might be noticeable if the new clutches don't work properly. The flares looked good so hopefully no problems there.
I tried without success for quite a while to try and bend the bracket down to tighten the spring. I decided I'll to need take it apart again so the first thing I did was push the piston back in the slave cylinder and take the actuator pin out. Wish I would have thought of this earlier. It gave a lot more room to get my hand in there. I clamped a small vice-grip on the spring and used a flat screw driver against the slave cylinder to stretch the spring off the bracket. Way easier to stretch the spring. I moved to the spring up a hole and put it back on the bracket and presto, it's fixed.