[68ragtop]

Pulled my hydraulic pump apart last night as one of my last items to go though on my restoration. Quite a bit of crud inside the oil reservoir, but otherwise pretty clean inside. Also one of the check balls is grungy & probably leaked a little causing the pump to run slow one in one direction.

Anyway, I am curious if anyone knows where to get the reservoir o-ring & the motor shaft to pump o-ring. I haven't measured it yet, so they could be a common size?

Also, both lifting rams were not leaking & seemed to work well, however When I pull the shafts out I noticed they have some small pitting in the chrome (or nickel) not sure what those are coated in. I would think any pitting at all could cause some oil leaks, but they appear to be ok. They appear to be non serviceable & also curious how decent the replacements are.

Oil that was in the system reminded me of something between brake fluid & power steering fluid. Very clear fluid in the rams, a little darker in the pump. This system has been sitting for decades, not years

Any thoughts?

[kk68]

Mine sat for 20 years out of the car but the system stayed connected (pump, hoses and rams). I rebuilt couple years ago and got everything back working. Bought new rams (lift cylinders) as one of mine was beginning to leak (if replacing need to change both sides). Bought a rebuild kit for pump/motor that has the internal O rings and seals needed. Used my original hoses/lines. After rebuild of pump/motor, refilled with ATF as recommended. Bought cylinders and rebuild kit from Convertible Top Specialists in FL. There are other reputable vendors for convertible parts as well. There’s also a number of good threads on here that helped a lot. Run some searches and you’ll find some good stuff, including rebuilding the pump. I think I posted several times while doing mine.

[68ragtop]

Thanks for all the thoughts & advise, I will do some deeper searching.

I have two pumps, one I got from a 69 Cutlass years back. They look to be the same, except it has a yellow cad plating on the fluid reservoir where the 68 Pump I have is clear/silver.

I am guessing the tops of the rams are pressed into the aluminum housing? The two that came from the cutlass are fairly pitted & look like they were probably leakers. I might see if I can get one apart just for giggles.

[68ragtop]

Some of those rams on ebay say they are made in the USA & look like they might be quality items. Are these the same that our host & others are selling? I have another parts wish list growing.....

[stevep]

Since I am in the transmission business, I used the servo cover O ring from a Super Turbine 300 transmission for the top reservoir O ring and it has always worked well.

[68ragtop]

Went through my assortment of nitrile o-rings & stoped at my local hardware store & not having any luck finding the correct o-rings for the reservoir bolt & the motor shaft. I think I am going to end up reusing the large reservoir o-ring, but so far I found nothing that fits correctly. Everything else is ready to go back together.

Also guessing it would be hard to find the black braided jacketing for the ground wire? I am figuring on replacing it with a standard black wire so at least its black & not white if nothing else.

[68ragtop]

So I was looking at the line connections and they are clearly standard compression fittings. So, I get out my "new" lineset & they have no compression contact area. in fact, the flair is so lousy it would probably push right through the nut if tightened. No way these are going to seal.

I have been so disappointed with so many of all of these aftermarket parts. Many thousands spent & very little is worthwhile.
Look great in the books though....


technology was clearly better 50 years ago.....

[PurelyGTO68]

I installed my Ames hose kit today and it sealed fine. No leaks or issues. Top operates smoothly. I ran it up and down several times and checked for leaks but every fitting looks dry. Will check again in the morning.

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[68ragtop]

What bugs me is the original compression fittings snugged down & sealed to the tapered center inside the fittings where I made the yellow arrow. Thats how I would expect a hydraulic fitting. The new kit doest even contact it, it just presses into the o-ring & thats it. I can see that getting loose & leaking.

you can see the contact lines on both if you look close.

.

[68ragtop]

Looking closer, one of the flairs is tighter than the other & looks like it might seal. Maybe if I file the edge flat on the other one it will work.

I'll look closer at the other hose tomorrow & report back.

[68ragtop]

Originally Posted by PurelyGTO68

I installed my Ames hose kit today and it sealed fine. No leaks or issues. Top operates smoothly. I ran it up and down several times and checked for leaks but every fitting looks dry. Will check again in the morning.

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Did you replace the lifting cylinders too, or just the hoses? just curious.

[PurelyGTO68]

Originally Posted by 68ragtop

Did you replace the lifting cylinders too, or just the hoses? just curious.

I replaced everything. Pump, cylinders and hoses.

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[68ragtop]

Is your pump a rebuilt original, or aftermarket? Are the hydraulic fittings on the pump & cylinders the same as the originals? I have been thinking about ordering a set of lift cylinders. The ones I have seem to work fine, but the shafts have some really small pitting that visually dissapeared with an sos pad, but I am worried that will cause leaks at some point.

[PurelyGTO68]

I ordered everything from Ames. The pump looks new but it could be reconditioned....not sure. It has a sticker that reads Convertible Top Specialists 352-897-4800. Topsdown.com

They might have rebuild kit for the pumps?

The fittings looks like the originals except the originals had cadmium plated nuts where the replacements are brass. Otherwise they look the same.

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[PurelyGTO68]

Also looks like the replacement pump has a yellow power wire where the original pump wire color was green...

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[PurelyGTO68]

After a closer look...
The replacement pump is new. ..not a reconditioned unit. The case design is different so if you want an OE appearing pump then you might have to find the parts to rebuild what you have or perhaps send it out to a shop that specializes in those things. I think I will be fine with the reproduction pump since its hidden by the well liner anyway. Will keep the OE pump in case the next owner wants to swap it out later.

BTW, I made up my own filler tube and it worked like a charm. I purchased a cord protector and some poly tube at ACE Hardware. Insert the cord protector first and then slide in the poly tube in to make the seal.

Do you have the Fisher Body Manual with the section that talks about filling the system with fluid?


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[68ragtop]

Looking Great!

Yes, I do have the manual. My parts are all reconditioned, just need to order two seals. I figured out the size by purchasing a bunch of them from my local hardware store, however they are for water faucets, so they are serving a sizing purpose only. I will order some viton seals, or find somebody who has them next week.

What type of fluid did yours have in it? The pump I am rebuilding came from an april built (pontiac MI) Lemans. I was surprised to find it had brake fluid in the system, I thought that ended in 1967? I suppose there are exceptions to everything.

As for the fittings on the Ames lines. It looks like they will work. I took a file to the ends & now they don't go as deep into the fittings when tightened. There was really only one that was bad. the rest probably would have worked. But either way, they really crush the flat o-rings & the contact point is very deep into the brass connector.

Also, I noticed your oe pump had a sticker on the reservoir. Mine had the same. I wonder what that was. I see those stickers available that say "type a automatic transmission fluid" But, this one I have was brake fluid, so it must have said something else.

To your point about the bag hiding it. I keep wondering why I am getting so carried away with something nobody will ever see.

I also found they have a date code on them stamped into the aluminum center section The one I am rebuilding has K7, which might have something to do with the brake fluid. I wonder what the advantage was? I am guessing less pump load seeing its a thinner fluid?

[PurelyGTO68]

I am not sure what the sticker read....mine fell off some time ago. Also not sure what fluid type was in there since the lines were broken and all the fluid was drained out when I bought the car in the late 80s.

Here is a photo of the end of the pump. This is a late May car from the Arlington plant

In the 50s and 60s, GM transmission fluid was the same color as engine oil. They didnt add the red color until sometime in the mid or late 60s. I am not sure when exactly. Is it possible you have type A fluid that is the uncolored type?

I will try and research when GM type A fluid changed the color to red and report back.

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[PurelyGTO68]

So, according to my charts....GM Type A fluid was created in 1947 and used until Dextron was released in 1967. I presume GM started to phase out Type A around that time. If I read the charts correctly....Type A was a honey color....just like new engine oil. I don't see any reference to a revised formula to add the red color. The Dextron fluid was red according to the charts so maybe all Type A was honey color?

The books I have say that GM pretty much invented automatic transmission fluid and Type A was where it all started it seems. They changed the formula in 1967, added the red color and changed the name so people would stop pouring engine oil in their transmissions.

I was not able to purchase Type A at any of my local retailers. I did find several references that say a 50/50 mix of Type F and Dextron is nearly identical to the GM Type A formula so that is what I did.

Years ago I had a 67 Cadillac convertible. The fluid in the lines was a brown color.

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[68ragtop]

Wow, thats some great info. It is possible its trans fluid. I still have some of it. It smelled a lot like nasty brake fluid & very thin, so I just assumed. The oil in the pump was quite a bit darker that in the cylinders. Seemed like moisture in the reservoir might have effected it, but really not sure.

The date is stamped on the main aluminum center section. If you held it upside-down should be in line with the mounting brackets. Very pronounced on the 68 pump. can barely make it out on the 69


Took my top mechanism all apart today. That was a project. I had left it together with the top & rear glass still installed so it wouldn't sit in pieces for years on end.