kens69olds

When I bought the car the top worked properly. After using a few times it slowed and eventually stopped working. I noticed a pool of dark fluid under the driver's side back seat. Sure enough it was fluid from the convertible top cylinder.

I took off the arm rests and tried bleeding the system again (there was a brown fluid so I assumed it was hydraulic fluid and not ATF - so I bled it with hydraulic as to not mix in ATF and have further issues).

With the armrests off and cylinder exposed I began bleeding and heard a sucking, air sound and saw that the fluid was spitting out of the top of the cylinder where the rod that goes in and out enters the cylinder.

Can anyone help me determine if that cylinder is shot or repairable? See pic. Where my finger is pointing is where the fluid oozed out during bleeding the lines.

Thanks a ton!
Ken

Fun71

All of the cylinders I have seen are roll crimped on the end and therefore are not repairable. It would probably take only a few seals and o-rings to repair if there were some way to open the crimp to get the guts out and then re-crimp it after putting everything back in.

You could check with a hydraulic repair shop to see if it's possible to repair, but with new ones around $120 each the repair cost would need to be pretty cheap to make it worthwhile.

kens69olds

Thanks Fun71. I found someone selling the cylinders for $104 each on ebay. Makes sense to replace the faulty one and call it a day.

Appreciate your reply. Any chance you know how to bleed out the old fluid from the lines that go from the top pump to the cylinders? I want to fill them with ATF but they currently have hydraulic fluid.

Thanks

Fun71

I have never actually worked on the top hydraulics, but is should be similar to any other hydraulic system (such as the brakes). You would need to open the lines and move the cylinder pistons up and down to push the old fluid out, drain the reservoir, then reconnect, fill with new fluid, and run the cylinders up and down to get rid of the air.

'69CutlassVert'

IMHO if you have 30-40ish year old hydrolics, if you replace one, it increases the back pressure on the other seal and it pops pretty soon. Cheap enough to replace both and put another 100 into a new set of hoses. You'll do it once, and be done worrying about it.

kens69olds

Good points. I did replace both cylinders but now it seems the pump is overheating and cutting out about every 5 seconds when operating. Then after waiting about 30 seconds, it goes another 5 seconds before cutting out again. Saw smoke coming from the motor at one point. Time for a new top motor?