Caterpillar 246 - Parking Brake Solenoid & Manifold Replacement

[01Time]

Can anyone provide guidance on replacing the Parking Brake Solenoid & Manifold on my Caterpillar 246 (s/n 5SZ07867)?

 

[heymccall]

This thingy

 

[01Time]

Dealer did a test and said that parts 195-9700 and 208-0973 need to be replaced.

BRAKE TEST FAILED 28 PSI SHOULD BE READING 0 PSI​

I'm trying to figure out where these parts are specifically located and what is the proper way to remove the old and reinstall the new.

This is from the Caterpillar parts website:

 

[Nige]

#7 in the illustration below.
Question. Why would on earth would they want to change the manifold.? It's only a block wth holes drilled in it. Unless it's cracked or something like that.

 

[01Time]

#7 in the illustration below.
Question. Why would on earth would they want to change the manifold.? It's only a block with holes drilled in it. Unless it's cracked or something like that.

That is a good question. I don't think their recommendation was based on anything other than the test they performed. I would hope it's not an attempt to take advantage of my naivete of the matter. Maybe they were quoting worse case scenario so that I would be prepared if the cost was more than expected? I didn't get the feeling they were out to take advantage of me.

I'm guessing I should be able to remove the manifold to inspect it (while replacing the solenoid) and reinstall it if there are no physical defects?

 

[Nige]

I'm guessing I should be able to remove the manifold to inspect it (while replacing the solenoid) and reinstall it if there are no physical defects?

You guess correctly.

 

[Mark250]

this one

 

[01Time]

Are the lines going into the manifold under pressure when the machine is not running?

 

[Nige]

Shouldn't be, but always assume in the worst case that they are. Suggest to start by cracking the two steel lines (circled) carefully, then follow with all the others until everything is loose. If any line has pressure it will start to lose oil in a big way as soon as you crack the union nut on the line.

 

[01Time]

I was able to knock this out yesterday - much easier than I initially thought it would be when I decided to do this. Thank you to everyone for their help on this. I also was able to get some information from what I believe is the service manual. Below are some photos I took along the way, and at the bottom the excerpt from the service manual.

A few notes:

• I found it to be easier to perform this procedure from the side of the machine where I could stand and reach through the (grounded) lift arm. I initially began while seated inside the well, but it was awkward leaning outward and downward to do the work.
• Before I removed anything, I sprayed the area down with brake cleaner to make sure nothing got into the hydraulic system while it was opened up.

1. When you raise the cab, it is on the right hand side (just behind the left joystick if you were seated in the machine).
​

2. As recommended, I just cracked the tension on this fitting. It confirmed that there was no pressure in the system and I proceeded to the next step.

3. The only two things tethering the solenoid to the machine is the wiring harness and the socket screw.​

4. If my memory serves me, it was 6mm.
Be aware, once you remove this bolt and the solenoid bracket loosens - hydraulic fluid will begin to flow out of the port of the vacated solenoid (not at a high rate, but enough that you need to be ready to place the replacement solenoid in its new home as quickly as you can).

5. The re-installation is as simple as reversing the steps.
​

 

[Nige]

$64k question. Did it fix the problem..?

 

[01Time]

$64k question. Did it fix the problem..?

That's a bit of an unknown at this point. I wasn't having any outward symptoms quite yet. The dealer did a pressure test and told me that the solenoid was failing and at some point it would fail and the parking brake would not release. Since I am going to have this out on some land that's an hour and half from the nearest Caterpillar dealer, I wanted to be proactive and fix it before hauling it out there. And since the part was only $80 or so, I thought it was worth the half hour of potentially unnecessary work versus it breaking down on me while I'm in the middle of something.

I am tempted to get the pressure retested, but I feel like that would be a (possible additional) waste of money at this point.

 

[Nige]

I am tempted to get the pressure retested, but I feel like that would be a (possible additional) waste of money at this point.

Personally I wouldn't bother unless the dealer is doing any other work at the same time.
Having residual pressure in a park brake is not a good thing though. It could mean that at some point the park brakes themselves might not apply at all and the machine could roll away if it happened to be parked on a slope.