Brake Proportioning Valve Tool

Contributed By: Michael Baxter

There are two different combination valves (what Jeep calls the proportioning valve because it does some other functions) used on all the years I'm familiar with. The D type and the W type.

Crawl under your FSJ and look on top of the valve where the inlet ports (lines coming from the master cylinder) are connected on either side of warning light switch. Are the inlet ports embossed or raised above the mounting surface of the warning switch? If so, you have the W type. If the inlet ports and warning switch are all on the same level machined surface, you have the D type.

The D type requires pushing in the valve stem located under the rubber boot at the front of the valve while bleeding the brakes. The W type requires pulling the valve stem out. On both you need to remove the rubber boot to see the stem.

I've only dealt with the D type on the 3 FSJs I've spent quality time under. A 6-8" long piece of approx. 1 inch wide metal strap is all you need to fabricate a tool for the D type. Just bend it over 90 degrees and cut a slot in one end for the forward mounting bolt on the valve. Loosen the bolt, slide the fabricated tool's slot under the bolt and then tighten it such that the valve stem is being depressed.

It's real easy to make the D type tool as long as you have a way to cut the slot.

-- Michael Baxter

From Reno, NV USA on 04-Jun-1997 at 23:58:25 PDT