Cat 769b

1. #1lantraxco2015-05-30 01:05

   Take it to the circle track?

2. #2Nige2015-05-30 04:36

   I would have thought the obvious place to look would be the HMU (aka Orbitrol valve) to see whether or not you have pressure coming out of the port that supplies the oil for a "right turn". BTW, you say it steers left but not right. Does it steer left and back to the centre position or just steer left to full lock and stay there..?

3. #3barryzz612015-05-30 04:40

   Just steers left and not and you have to fight the steering back, been chasing hydraulic lines and been cleaning spoold

4. #4Nige2015-05-30 04:48

   I need to correct myself here. That truck is too old to have an HMU, it has a rotary control valve mounted on the left frame rail. Either way that's probably where the issue is.

5. #5barryzz612015-05-30 05:04

   Spools

6. #6barryzz612015-05-30 06:11

   Stays there

7. #7Nige2015-05-30 06:14

   You have mail ...............

8. #8barryzz612015-05-30 07:30

   [email protected]

9. #9kshansen2015-05-30 08:01

   Glad you sent that I would not want to get accused of being a wise guy! Looks Like Nige has already got some good information heading his way! I'd have to do some reading to refresh my mind on that one's system. I'd be tempted to remove one hose from the cylinder, the one that turns it to the left then try turning it to the right to see if the oil is by-passing the cylinder(s).

10. #10Nige2015-05-30 10:58

    I had to think a bit (and got it wrong first time up) about the steering system on a B. I haven't seen one in the flesh for maybe 20 years.

11. #11tctractors2015-05-30 16:06

    Nige, about 5 years ago I was working on a site with 5 of these chariots chugging about (Stratford upon Avon), 2 had air start but I don't think they will catch on here in the U.K. due to all that electrical equipment on board like head lights etc. tctractors

12. #12Nige2015-05-30 16:12

    S'funny. All our large mining trucks with 3512, 3516s and the like all have air turbine starters on them. One 30-pound air starter would do the work of 2 x 50MT electric starters. I know which one I'd rather change if I had to, plus the fact that the air start trucks only had a couple of 750CCA batteries compared to the 4 x 1400CCA batteries on the electric start version. http://tdi-airstarter.com/air-starters/t50-p

13. #13lantraxco2015-05-30 17:18

    Yup, air for sure, drive up with your service truck, snap an air line on a quick coupler, two swallows of coffee and you're ready to roll her over. And over. And over. When troubleshooting a dead engine or bleeding fuel lines, etc. an air rig will run practically nonstop with little consequence, no waiting for starter motors to cool or batteries to recharge, never mind the explosive hydrogen off-gassing.....

14. #14tctractors2015-05-31 02:29

    I love the air rotor starting it sort of takes me back some, the Dumpers are still on the same site snoozing, I have been keeping my eyes on them via a spy on the site who will call me if anything evolves, my interest being the overhead cam motors and drive dividers that are good spares for motor scrapers, the owner of the trucks I know very well and have done many jobs for him on Hi-Drive Dozers, but my spy on the site is a sound answer to help me buy the lumps I want if they get chopped. tctractors

15. #15nicky 68a2015-08-17 03:59

    TC.I have a good repaired D343 starter you can have if you buy a 769B

16. #16tctractors2015-08-20 01:51

    Nicky, I know you have a Drive Dog in stock? tctractors

17. #17nicky 68a2015-08-21 07:43

    Yes mate,you can have it for nowt.it looks new and I will never use it