Convertible hydraulic top raises unevenly

[Durandal25]

Team,

I've scoured the web and gleaned a lot of interesting perspectives on this issue. My 67 convertible top struggles to lift of the drives side. I flushed the system. Checked the frame and everything seems to be in working order. The lines seem to feed the fluid. It lowers evenly. I don't want to just replace components if these are good. I was thinking of taking the pistons off and test them separately to see if they sync up then assess the frame again....

thoughts?

 

[odcics2]

Agreed.
Or one side is binding up.

 

[Durandal25]

Given that the hydraulic pressure should be even, from the "T" fitting. Pretty easy to follow. I'm getting some new mounting grommets from The Convertible Guys site and will beef this thread up with the testing.

 

[JimCoronette]

I would make sure all the pivots in the frame move freely. Shoot some penetrating oil into each pivot point and exercise the top up and down.

 

[Durandal25]

So.....one little wrinkle that may be part of the issue. The actual instruction on this unit calls for the car to be running....at slightly above idle. I'm sure this motor needs more juice to get it going. I'm just using a battery.

 

[theman440]

One of your cylinders could be bypassing internally.

 

[dadsbee]

One of your cylinders could be bypassing internally.

Good point.. run into this all the time with amphib float main gear actuators. Durandal... once you have BOTH cylinders fully out (or in), remove the line at the now BOTTOMED out end of the cylinder..put a rag over it and hit the pump again in the same direction. Should be no fluid come out.. if there is your piston skirt seals are bypassing.

 

[Durandal25]

One of your cylinders could be bypassing internally.

.....yeah, could be an o ring issue......but I wonder if its rebuild-able.....

 

[theman440]

.....yeah, could be an o ring issue......but I wonder if its rebuild-able.....

I don't think they are rebuildable - I know you can buy new ones.

 

[1 Wild R/T]

One of your cylinders could be bypassing internally.

Exactly... Seen it before... Replace the diver side cylinder.... And know the passenger side will likely fail soon....

 

[Ron H]

I had rebuilt my top in steps ending with a new motor and hyd lines. I refurbished my old motor and when finally going to a new one it was a world of difference with speed of operation and reduced noise. As posted, the top itself could be hanging up on one side. I had found a snag point in mine due to cylinder torquing (shifting) that slightly hung up but assume you've already studied that. There may be bushings at the base that have become worn letting the cylinders shift about sideways. In my case I added new bushings to reduce the movement.

 

[theman440]

If your lines are more than 20 years old I'd replace 'em.

 

[PeteyDaMan]

I'm wondering if it's possible to swap the cylinders side to side and see if the problem follows the cylinders or stay's. That would let you know where the problem lies.

 

[Durandal25]

So.....to add an interesting update to this.....I was working on the top and a buddy of mine who works with hydraulics all the time asked me how long it had been sitting , and he noted that the system may just have needed to be manipulated more. We moved the top up and down several times by hand.....carefully forcing it down until the seals took. Once they they did, boom....no lag.

 

[Ron H]

So.....to add an interesting update to this.....I was working on the top and a buddy of mine who works with hydraulics all the time asked me how long it had been sitting , and he noted that the system may just have needed to be manipulated more. We moved the top up and down several times by hand.....carefully forcing it down until the seals took. Once they they did, boom....no lag.

The system in my car used brake fluid; when I got my new motor a couple years after putting in new cylinders converted to power steering fluid. Removed the cylinders flushing them out and installed new hoses. Over the years before restoring car some seepage of fluid did a total number on the paint at the motor and fittings.

 

[Durandal25]

The system in my car used brake fluid; when I got my new motor a couple years after putting in new cylinders converted to power steering fluid. Removed the cylinders flushing them out and installed new hoses. Over the years before restoring car some seepage of fluid did a total number on the paint at the motor and fittings.

So, back in the day they had type "A" tans fluid. There are a few replacement choices out there, and power steering fluid is one of them. I went that road. The best way to handle the flush was to just siphon out the old fluid...and try not to get air in the lines, but then fill and cycle up and down three or four times. The amount of fluid in the lines is minimal, so draining them totally may make a flush more irritating.

 

[SassyPants]

Dur25, sorry that I did not see this earlier. That is exactly how mine acted until I ran it up and down several times, with the top plug out, and now it works fine. For some reason, mine got some air in the lines that needed to be Bled out. According to what I read, the bleeding process is to take out the top plug on the pump and run it up and down several times. That worked for me. Best, B.

 

[MoparForLife]

Thank you gentlemen, I was having an issue with my convertible top going up. I checked the fluid level which was fine but I immediately feared the worst.

I bought the car last year after it sat for almost 30 years in a private collection/museum. I’ve been replacing everything rubber, plastic, cork/paper, and plastic for the past 10 months and thought this would be one more thing.

Thankfully, I searched the forum to see what the experts had to say, and once again, y’all were spot on!

I did exactly what DuRandle25 suggested, and it’s going up and down without any issues! One less fire drill before we leave for Carlisle.

Thanks again, Gentlemen!

 

[Durandal25]

Thank you gentlemen, I was having an issue with my convertible top going up. I checked the fluid level which was fine but I immediately feared the worst.

I bought the car last year after it sat for almost 30 years in a private collection/museum. I’ve been replacing everything rubber, plastic, cork/paper, and plastic for the past 10 months and thought this would be one more thing.

Thankfully, I searched the forum to see what the experts had to say, and once again, y’all were spot on!

I did exactly what DuRandle25 suggested, and it’s going up and down without any issues! One less fire drill before we leave for Carlisle.

Thanks again, Gentlemen!

......weeeee, even a goober like me gets it right some times!