Hydraulic Lifting Cylinder is leaking
 

It appears that the cylinder on my '80 FunChaser has sprung a leak and I need to replace it. Upon checking I cannot see how it is possible to remove the cylinder without some serious dismantling of some of the cable controlling rollers. Any suggestions? Thanks

jedelen, Hi! I've done three cylinder remove/replaces. Basically, with the trailer lowered, a tarp on the ground/cement--take several pictures of pulley placement, locking bar and guide rod placement, etc. I then blue taped the Front Lower cable "FL" same for Rear Lower "RL". Your piston should be almost fully retracted. I use a plastic wire tie(zip tie, medium duty to tie the cables as tight around the pulleys as I can, remove the bolt and washer and again zip tie them out of the way, try to keep SOME tension on them. CAUTION: the locking bar is not held in with any fasteners, it MAY fall after the next step. Ask me how I know. There is a taper type pin on the guide rod-remove that pin SAVE IT! Slide the guide rod to the street side until the curb side falls out. Once free of the HUGE plate, put the pin back in. Using two open end wrenches, remove the locking nut , then the retainer nut from the piston end. AGAIN CAUTION! the Heavy plate will come down (FAST) upon removal from the piston rod end! AND that locking bar!
Next- street side, This area is not the easy end because of space and ingenuity is needed. Carefully remove the "B" nut on the hydraulic line, cap it or use a zip lock bag to prevent contamination. Keep it out of the way without kinking it. Remove the plastic vent line and allow it to drain into a container. ALSO remove that stainless adapter where the "B" nut was attached. On the piston end, remove the cotter pin, nut, washer and then with what ever safe method you can, remove the large pin and the piston should come free. Safely remove it from the trailer.
When you have it repacked ensure you let then know that it is filled with Dextron 1 thru 6 Automatic transmission fluid-- not a hydraulic fluid. Should be bench tested to 2600 psi.
My preferred shop caps and tapes the piston mounting areas, sand blasts it with 220 grit, re-builds it, tests it to 2600psi then primes and paints it gray. Re-install in reverse order. When you raise it, only go about 3-6" several times to get any trapped air out. Then raise and adjust cables if necessary.
I assure you it's not hard, just makes your brain work (or get soft). Take your time, you'll see how it needs to be done.
Best of luck, let us know how you make out.
Long quick reply
Tree

Nice description, Tree. WE should all bookmark that.

Rick

Agreed! Excellent writeup, Tree!

A Moderator could copy this to the Hi-Lo Lift System section and make it a "sticky".

- Jack

Humm...Could let it ride for a while in case anyone can add a tidbit or two, marry them together then make a "sticky". Just hope it can help someone. Sure saves the money.

Tree, if this forum is anything like the F150 forum I moderate, you can add to a sticky unless a Moderator "closes it". Making it a sticky simply places it at the top of the subforum, where it's easily found.

As a Moderator, I'd copy the post to its own thread in the Lift Section and "Stick" it.

- Jack

Don't want to step on toes. Perhaps a Moderator will do that, here's hoping
Thanks Jack

Your wish is my command!

That's an excellent suggestion.

Yes, I think anyone can place those on the Forum. That's how all the Brochures and Manuals got there.

Rich, Thank you good sir!

But I think it takes a Mod to "stick it", right? Thanks for doing so, Rich.

- Jack

That's a good question. Moderator instructions are rather sparse.

HiLo problems
 

I want to raise a flag about something treeclimber said in his post. He stated that if the hyd ram was resealed to use dextron 1 to 6 to fill the system. I have in the past thought this was correct also. I have a allison tranny in my silverado an I just started following the Transmission section of the duramax forum. One of the experts who post on that forum was the fluid engineer for Allison that wrote the specification for the transmission fluids approved for use by Allison says that Dextron 6 is not compatable with the earlier Dextron fluids. In 2006 Allison put new types of seals in their transmissions that are compatable with Dextron 6 but Dextron 3 is to be used in transmissions built before 2006. They found out that Dextron 6 that had been put in pre 2006 transmissions caused the seals to harden and caused leaks. For anyone wanting to research this further go to the duramax forum and the oils and fluid section of that forum. The engineer's handle is hzjcm8 and you can search for his post. There are 98 pages on just the transmission fluid subject.

Jim, you should add that to the Sticky! Or Rich can do it if he gets here first.

- Jack

I'd better check my supply of fluids. I'm sure at the time of my rebuilds Dextron only went to IV, and I've had no problems , so I feel safe.
Tree

Thanks so much. I'll let you know how I fare.

Salango
 

I had the same problem with my 1979 Hilo Fun Chaser. Contacted a local Hydraulic Repair shop who agreed to replace the seals. He did so without removing the cylinder. Cost was about $400 dollars but the lowest cost of a new cylinder that I could find on line as a replacement was about that price and then I would have had to do it myself or pay labor charges to have new one installed. Repairs have worked fine, no drips, no runs, no errors.

Well, my project is done. Wasn't that difficult after my son came down with some muscle (he's a former football player who loved to lift weights). Got the cylinder rebuilt and got it back together myself - all works just fine.
Thanks for the advice, TreeClimber. Could add a few things to the work summary if anyone does the same job on a unit this old (1980).

Good for you jedelen! Feels good right? Every job we do seems to have a little variance to it, but as long as it works out we smile. Just returned form Rainbow Springs CG, saw the post.
Ya know when you get that feeling something just isn't right? On this trip, I didn't like the feel of my front end. All tires looked good and aired properly when I left. After set-up, took the TV to wally world and sure enough, belt separation on the left front. Two new tires and ALL balanced and things are right again. Listen to those feelings!
Tree

nothing to replacing seals dude easy as hell! mike