[jnorth]

Big thanks to Bill Pritchard for taking the time to write this up!!

Since this topic comes up periodically, I thought I would type, verbatim, the wording of the factory approved procedure for filling the power convertible top reservoir with fluid. This comes from the Fisher Body 1969 Service Manual. I have inserted my comments in italics.


FILLING OF HYDRO-LECTRIC RESERVOIR


This procedure virtually eliminates discharge or spillage of hydraulic fluid and possible trim damage while filling and bleeding system.

Fabrication of Rubber Filler Plug Adapter

• Obtain a spare rubber filler plug (Part #7596442). Might have to improvise here, as I’m sure these are no longer available.
• Cut approximately ½” off male end of plug (end inserted into reservoir) to permit insertion of tubing as shown in sketch. Sorry, can’t copy the illustration from the manual.
• Obtain a 2” length of metal tubing 7/32” OD x 5/32” ID.
• Insert reworked plug into filler hole in reservoir.
• Insert metal tubing through hole in reworked filler plug.

Filling and Bleeding Reservoir

• On all body styles, with top in raised position, remove folding top compartment bag material from rear seat back panel.
• On “B-C & F” body styles (full-size cars and Camaro/Firebird) remove rear seat cushion and back.
• Place absorbent rags below reservoir at filler plug. Using pliers, slowly pull filler plug from reservoir.

IMPORTANT: When installing new or overhauled motor and pump assembly as a bench operation, fill reservoir with hydraulic fluid. This priming operation is necessary prior to performing the following steps in order to avoid drawing excessive amount of air into hydraulic system.

• Install filler plug adapter to reservoir (already done in a previous step!) and attach 4 or 5 foot length 5/32 inch ID rubber tubing or hose to filler plug tubing.
• Install opposite end of hose into a container of Type “A” transmission fluid.

NOTE: Container should be placed in rear compartment (trunk) area on “A” bodies (Chevelle, Cutlass, Tempest, Skylark) and rear floor pan on “B-C & F” bodies, below level of fluid in reservoir. In addition, sufficient fluid must be available in container to avoid drawing air into hydraulic system. (Again, an illustration is referenced here, but I cannot copy it into this document…sorry.)

• Operate top to down or stacked position. After top is fully lowered continue to operate motor and pump assembly approximately 15 to 20 seconds, or until noise level of pump is noticeably reduced. Reduction in pump noise level indicates that hydraulic system is filled with fluid.
• Operate top up and down several times or until operation of top is consistently smooth in both up and down cycles and no further air bubbles are exhausted in container of fluid.
• With top in down position, remove filler plug tubing and remove filler plug adapter from reservoir.
• Check level of fluid in reservoir and re-install original filler hole plug.

NOTE: Fluid level should be within ¼” of lower edge of filler plug with top in down position.

CAUTION: DO NOT OVERFILL.

[pstonhead]

This is the procedure direcly out of the fisher body manual and for the most part it works well. However it cqn be adapted to give a better bleed. I found that by making a longer line of travel between the convertible top filler plug and the jar (place the jar on the floor or unbolt the pump from the bracket and lift it as high as the lines would allow you to) will able you to force more air out of the system. When I was finished I still had a couple of nasty air bubbles between one of the top fittings on the passenger side cylnderand the pump. When the cylnder was engaged for the up position the air bubble would flow back into the cylnder. Nomatter how hard I tried I could not bleed this bubble out. So I got a buddy to work the convertible top switch cracked the fitting bolt as he engaged the cylnder forcing the bubble out the fitting screw as well as a bit of tranny fluid and then retightened the bolt while the cylnder was still being engaged. The result a better bleed. Be careful as to not get any tranny fluid on your top. Good Luck.

[RazzFla70]

Thanks for posting how to fill the Convertible top. I have to replace the lines and it worked perfect as you described. Thanks

[70_ragtop_ss]

All-

Great tech article! Much appreciated. Quick question though, how do you go about finding one of the filler plugs? I have to replace one of the actuator arms and will need to fill the pump up when finished, but I only have one filler plug. I was thinking if I jammed a 7/32" rubber hose and wrapped a rag around it to keep it airtight, then put the other end in the trans fluid, it shoud work?

Any suggestions?

Thanks,
John

[HomerBear]

Has anyone replaced the soft lines with hard hydralic lines? I was thinking that this would be the only way to stop it from leaking, since hydralics are so popular.

[67red]

This is weird. I am sitting aat a car show this weekend when I notice a fresh spot of fliud under my 67 SS convertible in front of the rear passenger side tire. It was coming from a steady drip off the frame. After checking the brake lines, all that was left was top hydrolics. I put the top back up and checked it out when I got home. The fluid was leaking out of the top of the convertible top cylinder. It does not look like it is going to be easy to replace the cylinder, but it looks doeable. I thought I would get on the Chevelle Tech Forum this morning and search the Archives to see if there was anything there on replacing the cylinder or for bleeding the lines. I checked the Convertible Forum first and the very first topic was Convertible top bleeding and filling. Whats the chance? I am assuming that everything in this detailed explanation of filling the bleeding the power top reservoir will apply to my 67. If you know for sure please let me know. Has anyone recently purchased a convertible top cylinder? If so who did you buy it from are happy with what you bought? Almost everyone has them but the prices vary by $10-$15 up or down. OPG says theirs is the best and made out of aluminum at $175.00.

Thanks,

Gary D.
Michigan