The 300-F "Co-ordinated Washer" System
By: Dr. Tony Rinaldi
For one year only, Chrysler installed the "Cadillac" of washer/wiper systems in the 300-F. The Trico vacuum washer pump was initially used on the 1956-58 Cadillacs, with a different shaped reservoir and lid. The windshield wipers are co-ordinated to turn on automatically during the pumping of washer fluid and continue to operate for a short interval after the pumping stops to dry the windshield. Thus the name "Co-ordinated Washer" System.

The system is difficult to troubleshoot since little documentation was available in the original Chrysler literature. Fortunately, Trico supplied the "Co-ordinated Washer" System to Chevrolet for its 1958-62 Corvettes. A little known fact is that one of the models supplied had the exact same gray lid, pump and reservoir as used in the 300-F. Much of the information, in this article, was obtained from various Cadillac and Corvette vendors and restoration services acknowledged below.

The pump has four connections. Only the first three are plainly labeled on the gray lid.

  • 1. "Vacuum" is connected, with rubber tubing, to one of the two connections on top of the vacuum reservoir can. At least 15" of vacuum source is required to operate the pump.
  • 2. "Water Coupler" is connected, with rubber tubing, to the hose that feeds the two nozzles directing washer fluid to the windshield.
  • 3. "Control" is connected, with rubber tubing, to a valve in the back of the wiper switch. The front of the valve has a nylon rod that projects, through the center of the wiper switch and knob, and is connected to a push button. When the push button is pushed in and then released, the valve vents and instantaneously breaks the vacuum pull within the pump. This activates the pump and fluid is pushed out for 10 to 15 seconds. The Control head of the pump is marked with the number 88693.
  • 4. The last connector should be called "Co-ordinator" and is connected, with rubber tubing, to the Trico Windshield Wiper Co-ordinator Switch mounted adjacent to the electric wiper motor. When the pump is activated, vacuum is supplied to the Co-ordinator Switch. A vacuum activated diaphragm slides electrical contactors, within the switch, and sends electrical current directly to the wiper motor, bypassing the wiper switch. The Co-ordinator head of the pump is stamped with an "X" or "XN".


    There is a "bleeder" screw on the side of the pump. This adjusts the number of drying sweeps of the windshield wipers. To adjust, remove the screw and activate the pump to fill the side chamber with fluid. Replace the screw and tighten gently against its rubber gasket. Test the pump and note the number of drying sweeps. To decrease the number, of drying sweeps, unscrew the adjusting screw slightly and continue the testing procedure until the proper number of drying sweeps are obtained.

    A rebuilding kit, AWS-4, is available for about $50 from McVey's (913-722-0707), in KS, a Cadillac vendor. This do-it-yourself project is not for the faint of heart. Our experience was poor and we were not successful with our pump rebuilding attempt. The directions were sparse and McVey's support was dismal.

    A complete NOS pump assembly was obtained from W. F. Grossmueller (908-213-8832), in NJ, a Corvette vendor.

    Reconditioned (using McVey's kit) good used pump assemblies are sometimes available from earlycorvetteparts.com (858-451-1933), in CA. The assemblies are known in Corvette circles as "gray top washer bottles".

    Pump rebuilding services are available from Tom and Jay Maxwell of Capital Auto Restoration (301-948-9481), in MD. Tom claims to have rebuilt 150 pumps and has gaskets manufactured for their own use. They have a collection of various spare parts and have a jig to attach the rivets and assemble the pump back together properly. Tom was the most knowledgeable and forthcoming source of information contacted. We did not, however, have any experience doing business with him.

    You now have a good excuse to go looking for Chevy parts for your Chrysler 300-F.

    Tony Rinaldi


    Please click HERE to go back to the tech list !

    Please click HERE for the Club's Main page !