• Thank you for visiting HeavyEquipmentForums.com! Our objective is to provide industry professionals a place to gather to exchange questions, answers and ideas. We welcome you to register using the "Register" icon at the top of the page. We'd appreciate any help you can offer in spreading the word of our new site. The more members that join, the bigger resource for all to enjoy. Thank you!

Secondary steering system on Caterpillar construction machines

Pep Joe

Well-Known Member
Joined
Mar 5, 2020
Messages
111
Location
Abuja, Nigeria
Occupation
Heavy equipment technician
I need your opinion on the negative effect of driving a Caterpillar machine without its secondary steering system working.
Some Cat machines have secondary steering motor and pump equipped.

Thanks.
 

Nige

Senior Member
Joined
Jun 22, 2011
Messages
28,984
Location
G..G..G..Granville.........!! Fetch your cloth.
Secondary steering is only designed to operate as a safety device if the primary steering system pressure from the main pump fails.

Secondary steering (in general) is/was an attachment, optional extra in other wrods. Not all machines were built with it by the factory.

If a machine has it I like to see it working, especially the type of SS system that has an electric motor. On graders I've seen all sorts of weird things happen if the "detection system" from primary steering pressure goes on the fritz. In many cases the result is that the secondary steering motor burns out.
 

Pep Joe

Well-Known Member
Joined
Mar 5, 2020
Messages
111
Location
Abuja, Nigeria
Occupation
Heavy equipment technician
Thanks for your reply.
I've seen it on some newer motor graders like the M series and on 966h wheel loaders. Most of the problem I have fixed if it's not working or indicating a warning light were as a result of its electric motor burning just as you rightly said.

As you explained that it's for safety when the primary steering fail.
What then happen to machines without secondary steering system if the primary steering system fails?

Have you ever seen a Cat machine that its primary steering system completely fails on motion?

Most operators don't even know how it works and so they tend to push the secondary steering motor test switch and hold it in the test position too long and as a result burning the motor before its life span.
 

BillG

Senior Member
Joined
Mar 26, 2009
Messages
510
Location
S. Wisconsin
What machines are you running with aux steering and what conditions and terrain are they operating in. We have had machines come in from other areas that needed it where they were working but around here it is pretty flat. The owners would spend ridiculous money on something they didn't need but were unfamiliar with. After it was explained and the Cat dealer agreed they didn't need it they were disconnected to prevent problems with the rest of the system. The old Terex loaders with accumulator systems would fail without the operator knowing it. If you went down the road at high speed and let off the accelerator you lost your steering (more than once) and probably ended up in the ditch.
 

Pep Joe

Well-Known Member
Joined
Mar 5, 2020
Messages
111
Location
Abuja, Nigeria
Occupation
Heavy equipment technician
What machines are you running with aux steering and what conditions and terrain are they operating in. We have had machines come in from other areas that needed it where they were working but around here it is pretty flat. The owners would spend ridiculous money on something they didn't need but were unfamiliar with. After it was explained and the Cat dealer agreed they didn't need it they were disconnected to prevent problems with the rest of the system. The old Terex loaders with accumulator systems would fail without the operator knowing it. If you went down the road at high speed and let off the accelerator you lost your steering (more than once) and probably ended up in the ditch.
It's a 966H Cat wheel loader somewhere in Nigeria. The terrain is quite rough, it's a quarry.

My point now is why spending heavy on something you almost don't use?
I'm currently fixing one on 966H Cat wheel loader. The electric motor has burnt, will be sending the picture later as I don't have it now.

I was thinking to tell the owner to not worry about the indicator light that the secondary steering system that is causing the light is an attachment and one can leave it considering the cost of repairing it.

Plus I will also explain it's function to him and leave the decision of fixing it or not for him to take.
 
Last edited:

Pep Joe

Well-Known Member
Joined
Mar 5, 2020
Messages
111
Location
Abuja, Nigeria
Occupation
Heavy equipment technician
It's a 966H Cat wheel loader somewhere in Nigeria. The terrain is quite rough, it's a quarry.

My point now is why spending heavy on something you almost don't use?
I'm currently fixing one on 966H Cat wheel loader. The electric motor has burnt, will be sending the picture later as I don't have it now.

I was thinking to tell the owner to not worry about the indicator light that the secondary steering system that is causing the light is an attachment and one can leave it considering the cost of repairing it.

Plus I will also explain it's function to him and leave the decision of fixing it or not for him to take.
Later agreed to fix it. We changed the burnt motor armature and the brush holder that were burnt and motor is good now.
With the secondary system working, you can steer your machine even without engine running. Good one I can say.
 

Tyler d4c

Senior Member
Joined
Mar 2, 2016
Messages
1,750
Location
Salix Pa
Msha inspectors will listen to hear it self test and start writing if they don't hear it

So I'm told never witnessed in person.
 

Nige

Senior Member
Joined
Jun 22, 2011
Messages
28,984
Location
G..G..G..Granville.........!! Fetch your cloth.
On models where the electric secondary steering is an attachment how would an MSHA inspector know whether a particular machine machine was equipped with it.? Would they know where to look for the motor to confirm that the system was fitted.?
 

Tyler d4c

Senior Member
Joined
Mar 2, 2016
Messages
1,750
Location
Salix Pa
On models where the electric secondary steering is an attachment how would an MSHA inspector know whether a particular machine machine was equipped with it.? Would they know where to look for the motor to confirm that the system was fitted.?
No clue unless all machines after a certain year are to be fitted. I know a fellow to ask if I see him ill see what he says
 

Nige

Senior Member
Joined
Jun 22, 2011
Messages
28,984
Location
G..G..G..Granville.........!! Fetch your cloth.
Even on 2023 models of medium-size loaders an electrical secondary steering system is listed as an attachment, although with a caveat - "standard where mandated". I have no idea if the system is mandated in the US. I have personally never worked in a market where it was.
 
Top