# Bleeding convertible pump, lines, and cylinders properly



## cij911 (Oct 25, 2017)

OK I have seen a few threads on "purging" the fluid in the convertible system and most refer to the AMES kit. I have the AMES kit and the instructions and it really is not a true purge. Really all the kit does is "top off" / fill the system by connecting an external tupperware piece filled with ATF to the fill plug. 

How did you guys purge the old fluid ? The AMES instructions really are about "filling". Do you just use gravity method ?

Has anyone connected a pressure gauge to determine if the pump is strong enough ?

Also I have not found any specifications on the pump to determine if it is within operating standards (i.e. current draw, fluid PSI, etc.). 


I see AMES and eBay both seem to sell replacement pumps for ~$230 - $260. Are there any better (stronger and more reliable) options?

Thanks in advance!

Chris


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## cij911 (Oct 25, 2017)

Here is a copy and paste from a Chenille site and claims to be from Fisher Body Service Manual 1969:

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.


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## 60sPontiacs (Jul 14, 2016)

I see you found something while I was writing this, but will attach what I did.

I dug into this for a 67 GP. Was working okay until I tried topping it off, then fluid seeped past pump (small o-ring on shaft) into motor and that was the end of it. Old GM cars (pre-68?) used brake fluid, newers used ATF - I think I used hydraulic (or convert top) fluid but can't find bottle in garage w/quick look. 

Ah-found this link from when I discussed this on other forum (almost 3 years ago..).
67 Pontiac convertible fluid type, leak, and add - Hot Rod Forum : Hotrodders Bulletin Board

I used this kit.. $20, cheap.
https://www.ebay.com/itm/1955-And-N...m212739af54:m:mOlYVKX5S0hSaw-6sdDPaAw&vxp=mtr
These guys are good, but the "green" armature o-ring may not be green. It's same size but different material than two other o-rings in the kit. Black one seals, but being on an armature instead of static seal, I'd want the green (viton?) seal. Check around and maybe call vendors to confirm. I'm not sure if these (Hydroelectric) are the guys I got that kit from (whoever it was, changed their ad so it no longer said "green").

Pull the back seat if not already done. Pull armrest/whatever on sides so you can access/see everything and check for leaks. Good to take photos so if you pull all apart, you'll know how it all goes back together/lines are routed.

To "purge" air from lines, all you do is raise/lower top a few times. I can't remember sequence, but you fill it when top's either up or down (of course one or other, but it matters so you need to know..). With back seat removed, you'll see air bubbles in lines disappear as you do this. 

To "flush" the pump, cylinders, and lines... 
1) I'd remove the pump and rebuild it on a bench. Is easy. Problem with no power is either with motor (fluid leaked into it) or the check ball areas are gunked up. Pull it apart before you order a rebuild kit - if motor is bad, you need a different pump. Test the motor using jumper cables (don't run pump dry for long.. there should be enough fluid in it to test motor briefly - my bad motor growled and got hot fast).
2) I flushed cylinders by removing them, then moving rod up and down manually while collecting fluid (to see if gunk was inside). You can pull clean fluid back into them and flush out a few times. This can be messy - fluid will squirt far... proper way would be attaching lines and using a can to collect old stuff, separate can/ATF bottle to supply new fluid). Pushing or pulling rod makes fluid come out of top or bottom of cylinder, while it'd pull fluid into bottom or top. When removing cylinders, keep track of hardware, plastic bushings, wavy spring washers, etc (maybe stuff a rag into an opening, where if anything fell/bounced into, it'd be hard to get it out
3) Lines can get sediment in them - blow them out with compressed air, then maybe hook a clean tube to one end and suck clean fluid into them, then blow it out with compressed air. Seems if ATF, could use a can of transmission line flush. I wouldn't be concerned about getting these squeaky clean inside. If you pull lines, you could attach and flush them while flushing cylinders.

Curious about your symptoms. 
Top doesn't go up at all, Top goes up crooked, leaks, air in lines, goes up but labored, etc

My switch was bad - didn't get enough current to pump motor. You can test this by hooking 12 volts directly to motor (there's a common line, then one each for up and down). Motor also needs to be grounded well in trunk.

I never read anything about anyone needing a more powerful pump. I ended up getting a used Mustang pump for $50/ebay for the GP and just had to change with the mount (maybe transferred pump to motor?? my memory is bad, but it still works fine...). 

I had no problems removing hydraulic lines. IIRC, all were brass swivel connections that came off easily (I used a tubing wrench, but a good open end would probably work). These lines can be brittle and crack/snap, but then they needed replacing anyway... not too expensive.
http://www.hydroe.com/product_detail.html?id=10099&parts=Pontiac GTO 1969 - Convertible Hose Set

Lots of good info on HydroElectric site.


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## cij911 (Oct 25, 2017)

Thanks 60sPontiacs!!

I am restoring my 65' tripower and the car is pretty much gutted at this point so I figured it would be an easy time to change the fluid. Currently the top operates - fine going down and temperamental going up. The motor / pump look old from the outside and honestly I cannot see the fluid in the lines, so I suspect it is brake fluid rather than red ATF.

My plan is to disconnect the lines at the base of each cylinder and let the fluid drain into a pan under each cylinder. Then I plan on cycling the pump and pushing out the old fluid into said pans. Then I will fill the pump as much as possible and use the AMES tupperware procedure to do a proper fill.

Once the new fluid is in, I plan on running it a few times and listening / looking for leaks. Based upon the results I will decide next steps - leave alone, replace pump / motor (~$230), replace cylinders, or replace everything. 

I plan on making a video to share with other neophytes (like myself).

Chris


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## 60sPontiacs (Jul 14, 2016)

Nice car. It's something to hear from the actual owners of these classic GTOs (like your tri-power 65 convertible).

All these years with convertibles and my mind still struggles with if "top down" means opened or closed - it goes UP from my head when I open it and comes DOWN toward me when closing. I assume you mean top is OPEN when DOWN (this is MY problem... not with the rest of the world... when someone says put the top down, they always mean open it..).

When the piston is at the bottom of the cylinder, not much fluid will come out of the bottom hole (I think this is when top's closed) - the fluid would be in the top portion of cylinder... and not much would come out anyway because the cylinder is sealed at the piston (an equal volume of air has to go in through the opening for fluid to come out, which will be very slow with fluid through ~3/32" opening)... it wouldn't let air in even if you open the top line because the piston blocks it. And if you move the top, it can come squirting out fast and make a mess - is bad with corrosive (to eyes and paint) brake fluid. Tying a rag around it will stop fluid from going everywhere, but there's no danger of anything but dribbles unless the top/pistons or pump moves when lines are disconnected (nothing's pressurized with all at rest). Probably a good idea to wear goggles so fluid doesn't get in eyes if something happened fast.

It's hard to tell if the lines are full/empty with clear fluid, unless you can see bubbles. If top goes up/not down (or visa versa) it sounds like you're either very low on fluid or one of the check balls/valves are stuck. I'd think the pump/motor is good. Big hint is if the motor spins fast in one direction - been a while, but think when it did this I could see bubbles in the lines. This (working in one direction) would also seem to mean the pistons are sealing okay - if not (it seems) fluid would go past them in both directions.

Just did a search about mixing fluids/what to use... this is the toughest part of working on these. 
https://www.google.com/search?q=can+mix+fluids+in+convertible+top+hydraulics&ie=utf-8&oe=utf-8
Chevy guys are back and forth (because of changes in fluids/ages of cars), though BigDave (post 8) suggested flushing out old brake fluid and using Dot 5 silicone fluid (great idea, and silicone's good on rubber), since (it seems [my eternal disclaimer]) that new brake fluids should mix with some old residue without problem (brake fluid changes are common, but I don't know if systems have to be flushed with denatured alcohol or something first). Other problem with brake fluid is it absorbs water so can rust insides (though don't think pump had steel components other than check balls).
Convertible top pump fluid ? ? - Impala Tech
Mercedes guys are adamant about using the exact right stuff. Looks like some good general knowledge down the page.
https://mbworld.org/forums/clk-class-w209/487901-will-wrong-convertible-top-fluid-damage-system.html

The whole point is trying to save money on parts. I think you can get new everything (cylinders, pump, lines, mounts) for about $600 - then use ATF and you'll be set for good. Some diehard resto guys might want to use original everything (including brake fluid) but that's each owner's business. 

I'd be concerned about the pump seal leaking into the motor - especially if brake fluid's been working on a 50 year old rubber o-ring. There could be some leaking into the motor without causing damage. Maybe what I did was create pressure in the system when I filled it (top going up creates much more pressure than down, or v-v), and fluid went into the motor. When I opened the motor, it was a mess. For $20 it's worth a kit to learn about it - and you get 21st century neoprene seals (and maybe a viton? for the armature) .

It was easy to pull the cylinders - no tight spots to get wrench, etc. and then you can inspect the shoulder pivot bolts, plastic bushings, etc. I think Ames sells bushings etc. Flushing them as I said allows you to clear out crap that may be settled on top of the piston. Common problem is fluid leaking from tops of cylinders - they'll work fine if a small leak, but could cause the symptom you see if a bad leak... piston is sealed, but when it's going down, pressure is pushing against the rod's seal, and when piston is going up pressure is pushing against closed end of cylinder. 

I reread your post - if you open the bottom line and running the pump, it should pump fluid out - probably good enough, but I'd still disassemble, look at, and rebuild the pump (because of old seals). .


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## cij911 (Oct 25, 2017)

Again HUGE thanks 60sPontiacs!!!

Not exactly sure what the problem is, but my lines still appear to have a TON of air in them. The cylinders go up and down, but the system does not appear to be purging air as I thought it should / would. Additionally I cannot understand how the tupperware full of ATF will get sucked up (doesn't appear to) ? Maybe my seals are bad (ordered a rebuild kit), but I'm certainly not getting enough vacuum to draw the fluid up.

Thoughts ?

Thanks again!


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## 60sPontiacs (Jul 14, 2016)

Pumps like this don't really create vacuum. They have a lot of output pressure, which is why you fill the reservoir and run it to pump fluid through the lines. Eventually the bubbles get back to the reservoir where they float to the top, and air-free fluid is pumped back into the lines. 

Come to think of it, the three tops I've had trouble with opened (with the pump) easier than closing. Not sure why, though if it's MUCH easier for the top to open, maybe the air compresses enough to do so, but not enough to close it. This might be true because it IS much easier to push open the top from inside the car than it is to lift it out of the well to close it (I'd always assumed I was fighting fluid in lines but maybe it's also mechanics of the weight).

Is your back seat out? If so and it's leaking from the top of cylinder(s), there will be fluid under the back seat. You should also be able to see bubbles in the lines, but I'd hold off trying to fill it until you get a look at your pump to make sure the armature seal is holding. The GP pump worked fine until I filled it.

The HydroElectric site said have 3 quarts of fluid to fill a system, so might take a lot if empty, but I'd expect yours to be at least half full if the top opens.

Are you trying to "suck" up ATF from a container to feed it into the lines? If you have brake fluid, you'd be mixing the two, and that might not be good. You can research if there are problems with doing this - everyone I've read says not to, but I haven't seen anything from someone who did it/said it was okay. And it might not cause a problem right away, but could in time. You don't want to damage the piston seals. The pump wouldn't matter since there's no rubber in it (the actual pump mechanism) except for the o-ring the seals. Loosen a line to see if the liquid smells like brake fluid.

I haven't seen the Ames procedure - tried a brief search. Is there an inet link where I can see it?


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## cij911 (Oct 25, 2017)

Well my pump is shot, so I ordered a new one from Hydro-electric...Hopefully this fixes the problem .


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## 60sPontiacs (Jul 14, 2016)

How so? Motor bad?

Did you figure out which fluid you have/will use?


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## cij911 (Oct 25, 2017)

60sPontiacs said:


> How so? Motor bad?
> 
> Did you figure out which fluid you have/will use?


The pump was not creating enough pressure to raise the top....

I will use ATF as that is what is recommended by the manufacturer and won't damage the paint if it leaks.

Thanks for your help!


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## Mill Rat (Sep 29, 2018)

Hints on rebuilding the convertible top pump: Had to clean out the electrical side of the pump because fluid was leaking past the shaft seal. Getting the brushes back in place was the toughest part. Bent a sliver of about 20 gauge steel 1/8" wide x 4 " long into a U-shape with the ends of the U about 3/4" apart. That held the brushes in their holders as I put the end cap back onto the stator and armature. Once the commutator was part of the way between the brushes, I pulled the U out of the small gap left between the end cap and the stator and closed up the motor.

BTW, don't mix brake fluid and ATF. The gunk I pulled out of my system was horrid.

If you've got the pump, hoses, and cylinders out of the car, bench bleeding is the way to go. (They sure didn't follow the service manual method when they built these cars!) It'll take about a quart of ATF, but you'll about a pint more as I note later. Take one of the common rectangular quart bottles of ATF, find some way to hold it in a vertical position (I traced the bottom of the bottle onto a scrap 2x6, cut out the hole, chucked the 2x6 in my bench vise, and stuck the bottle in the hole.) Cut off the top of the ATF bottle about 1/2" above the fluid level, I used a pair of aviation snips to do that. Connect the hoses to the cylinders but not the pump. Stick the hose line Ts into the cut off bottle so the Ts are near the bottom.

Slowly stroke each cylinder several times. The air expelled with bubble up,and the ATF level will drop. This is where you'll add that extra pint of ATF so the Ts stay submerged. Leave the cylinders close to, but not at, the fully retracted position. One at a time, pull the lines out of the cut off bottle and attach to the pump without letting much fluid drain out of the T. Fill the pump reservoir most of the way and use the pump motor to make short strokes in each direction to get the air out of the pump. Then make a few full-length strokes with the pump motor to check full range of motion and catch any leaks before you put in back in the car. There were a few little bubbles I couldn't get out at the very last extremes of the strokes, but I doubt they'll cause any problems. Retract the cylinders fully, top up the pump reservoir to 1/4" below the filler and stick the plug back in. Run the cylinders out again so they're set to install in your raised top.

I used a battery charger to run the pump, just clipped the negative clamp to the pump ground wire, and clipped the positive clamp to a bare female spade lug that I moved between the molex connector terminals to run the pump in each direction, then plugged and unplugged the charger to run the motor. Do check the temperature of the motor, it can get pretty warm. Not designed to be run for any real length of time.

Hope that helps!


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## Mill Rat (Sep 29, 2018)

One more follow up: The new hose sets are about 4-6" longer than the A-body originals. (Probably a one-size-fits-all that covers the B, C, E, and F bodies too.) The cylinder top hoses don't seem to be a problem, but the extra length of the cylinder bottom hoses bunches up where the mechanism comes down, and had me worried I'd pinch those lines. Fix I found was to re-orient the T at the pump, so the line for left side went to the right, and the extra length gets taken up making a u-turn to go back left. Same thing happens to the right-side line then, of course.


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## swaayze (Jan 10, 2013)

So....thread resurrection.

'69 Lemans, top barely moving. Pulled seat and side panels. Motor looks good and sounds good. Lines seem to be in good shape (fortunately this is a very original car stored in a CA hangar for a dozen years prior to my purchase 9 years ago - if not for an old repaint/color change due to a quarter panel sideswipe it would be a fantastic "survivor"). Actually there's just a little fluid evident on cylinders and fittings, but lines are full of air (I guess 50 years of tiny leaks?). Ordered the Ames bleed kit and will get to work as soon as I have it. My question:

I'm thinking I'd like to have all the old fluid out, but honestly it looked good in the lines and is evidently trans fluid given the sticker on the pump. I'm thinking I should bleed/refill and see how well the operation is after that. If good and no parts needed then I'm tempted to leave it alone, but the ocd-me thinks then I should try to get all the old/new mixture out and then refill/bleed again with all new. Thoughts? And, if trying to get all fluid out with the motor in place I assume I'd need to disconnect all fittings (the main reason I may just leave the mix of old/new if the operation is good after the first refill; hate to monkey with them) and then operate the pump and the cylinders (these manually, of course) to expel all fluid. Is there a better way without bench service?

P.S. - FYI and FWIW the procedure outlined in post 2 is indeed from the Fisher manual; I have one.


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## integrity6987 (May 10, 2017)

My thought is - wipe it down, refill and if it works and is not leaking - give in to your temptation and leave the remainder alone.


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