Hello, I own an Allis Chamber model 21 Dozer. The problem I am having is that it won't steer to either side. Do you have any suggestions
I am not familiar with the Allis tractors but, I would bet your steering brakes need adjustment. Look for a cover on top of the rear case, it should be near the linkage were it goes into the brake housing. Unless you see a turnbuckle to adjust linkage, it should be an internal bolt to adjust the slack out of the brakes. Tighten it just snug, then back it off to get free movement (about 1/2 to 1 full turn). Run the tractor and make sure the brakes DO NOT HEAT UP. Any indication of heat will appear quickly and you will need to loosen adjustment or brakes will burn out.
Sir, thanks for you reply but I really need a mechanic that is fimiliar with the Allis Chamber HD 21
A couple questions on the dozer.
1.) Is it a knuckle buster or is it hydrostat.
2.) If it is hydrostat when was the last time the fluid and filters was changed.
I havent worked on one this old but have ran them i have a couple ideas as to what it could be if you could get me this info i have requested i can help you trouble shoot this problem.
It is a hdrostat. It has three filters on the right side by the firewall. If you know of an addition filter related to the steering, I"ll try that tomorrow. Thanks, DLC
I already changed the flsid and all the filters, to include the oil and fuel filters. Thanks, DLC
On this model i do beleive that on the hydraulic tank the cap acts as a breather you can either clean it or order a new cap.
The last thing that i think it can be is the controls you may have to pull the controlls off and see if there plugged if you have any hydraulic test equipment you can hook it up to hydrostatic junction box just under your feet and see if there is any pressure getting there if there isnt then you will have a bad check valve on the pressure side if you are getting pressure the check valve on the return side is probally plugged or bad try tapping the junction box and check valves lightly with a hammer that will sometimes free the valves up.
Dustin, I located a mechanic who will check out the dozer next week since it is at my ranch, it is somewhat difficult to get anyone to go. I'll share your thought with him and ask him to check out those items. If your diagnosis is correct, I'll contact you and authorize payment. Thanks for everything. If you think of anything else. Please advise. DLC
Hope I am not too late, I had to contact the guy I know with experience and a service manual on the Allis 21 you have.
I have a question for you on the steering. To test the clutches you will have to have the machine moving and pull down on both levers and not apply the brakes this should stop the machine, if the steering pump and hyd system is working properly to the steering clutches. If it does stop then a simple brake adjustment is in order. There are two plugs near the front of the rear end one for each side just off center towards the outside of the machine. The plugs are towards the front of the steering brake cover which will require removal of the seat and sheet metal. The plug should be 1" to 1 1/2" round with a hex bolt on top[. Once the plugs are removed the adjuster for the brakes will be under the plug. Machine must be running and in a gear to adjust. Place it in 1st and move your direction lever to forward move some the move the direction lever back to neutral, this will release the parking brake and you will be able to adjust the brakes. Spec call for snug then back off 1 and 1/2 turn, makes them rather tight on a good shoe you may need to go an additional 1/4 for smoother operation. You have a really tough dozer it has one of the best transmissions of the day and still stronger than a same size Cat. Hang on to it!
Hope this helps, if you have further troubles post back with your serial number one of us will be able to help.
Hello Bill, This is by far the best answer yet. My dozer is located at my ranch and it's somewhat difficult to get a tech out there. Based on your comments it make sense. The tech is supposed to be there next week and I"ll share your info with him. If it helps in the most remote manner I"ll release payment to you and give you a positive feedback. Thanks again, DLC
Hello Bill, I am going to accept your answer as it is by far the most correct. I took a tech to check it out today. As you said, the brake adjustment bolt were right where you said. We were able to adjust the left one but the right one was already adjusted all the way down. I think I need to replace the brake bands. How do I do that. How do I get them out. As far as the steering controls, I had no luck with them. The dozer set for about ten years, is it possible that the controls are frozen? I can see the control valves go in and out but they have no affect on the turning of the dozer. I also noticed that there is something like a adjustment cover behind the control valve.Cad you tell me what that is for. I saw that the cover where the control valves go into is secured by four boult and have several hydralic lines goiny into the cover.I can only assume that the hydralic pump is working OK as the front blade operates OK. This is a good machine and I think that with a liitle work it will last me several years as I only use it at my ranch. Thanks again, DLC
Hello again DLC,
Sorry to hear the adjustment did not cure the problem. We will work this out. Seeing that the control valves move in and out is good. There is a seperate pump for the steering other that the main hydraulic pump. I cannot access the information at this time, I will get back to you as soon as I can. When will you be able to get your tech out again?
The brake bands will be a big job.
Thanks for the accept!
Thanks for answering, The tech is just waiting for the answer. He is a heavy truck mechanic but doesn't know that much about my machine.Please let me know when you have the answers. Thanks again, DLC.