wrecker boom extension cylinder troubles....

[wcuhillbilly]

looking at a coating of hydraulic oil all over my toolbox/deck of the 816,,,, Yup its time to address the telescoping extension cylinder in the boom.
Anyone got a diagram or schematic of the "correct" way to open that beast up.... Looked in the wrecker sections of the TM but found mostly winch or bed related info.... figure this to be a Depot level repair.

I can knock the pins out and get the cyl out easy enough..... but pushing it back up in the rear of the boom and attaching the front pin is where Im scratching my head.... I shudder to think about collapsing the cyl and pulling the front boom out of the rear boom with the cyl in tow, then having to put it all back in there with a very geriatric shaky backhoe..... need another wrecker..... wife says one is enough.....

Got weather- (snowman poop ) coming in this week, thus Im not looking to get started just doing my homework, cant tell if its the packing or one of the lines that is leaking.

 

[gimpyrobb]

Posted in wrong thread, I thought this was Sean Connery's thread.

My bad.

 

[wcuhillbilly]

pondering my delima, To remove the captive extension cyl from the internal confines of the boom.... I could pop the pins and let the internal eye fall, turn the boom 45 or 90 of the bed and pull it out the rear of the boom. Now for re install,,, I could theoretically tie a block of wood to the inner eye to hold it up at the proper level as the pin would need to somewhat align and slid it in from the rear, pin it, lift to pin rear, and not worry about the wood block from here on after....
There is not enough room from the rear of the boom to the back of the cab to pull the cyl thus having to rotate the turret, 45 or 90....

 

[red]

http://www.roscommonequipmentcenter.com/TM 9-2320-260-34-2.pdf Chapter 15 covers the different beds on the m809 series trucks. Should at least have a diagram on there.

Haven't found this TM on this forum. We have volume 1, but not volume 2.



Diagram on page 514 starts to cover it. TM calls for completely removing the crane extension (ouch).

Can you access both the pins holding the cylinder in place with the crane extension still attached?

 

[doghead]

Removing a cab top is pretty easy.

 

[73m819]

I hate to say this but all 5t wreckers REQUIRE that the main boom with extension be REMOVED from the truck according to the -20s and 34s, then proper blocking, also proper slinging and a helper is required, all of this is to prevent the bending of the extension piston, the LAST thing you want to do is chit it out the back, a chance of dinging in the cylinder, or bending the rod.

 

[wcuhillbilly]

Thanks Red, that volume had the diagrams I was looking for,,,,, ouch,,, says to pull the whole boom, set it on the ground, and use an overhead trolley crane/chain hoist to pull the inner boom out of the outer boom. Then pull the cyl out of the inner boom..... yuck.... will have to look at it more when I get home... again,, still in the homework phase,,,, would be nice if its just the rear fittings,,,, but Murphy and me go way back and he would never let it be that easy.....

 

[doghead]

Stretch resealed his cylinder if I recall, and don't think he removed the main boom.

It was the baby wrecker...

 

[gimpyrobb]

Get some scaffolding to lay the boom on and take apart. Should be able to get the height pretty close.

 

[red]

In my experience working on the hydraulic systems in the oilfield it's normally not the cylinders that start leaking. Usually the hoses or the fittings are the culprit. When the cylinders did fail it was usually because crap got stuck in the seals and being that the telescopic cylinder is inside the boom it's better protected from the elements, less likely for that to happen.

If however murphy is ****ing with you again and removing the crane is out of the question here's what I'd do:
1. Rotate crane 90 degrees
2. Extend the boom out far enough that you can access the 3 holes along the inner boom sides but not fully extended. (crane support pin, cylinder pin, and a 3rd hole a few feet back)
3. Insert a solid piece of metal into that 3rd hole on each side of the inner boom. Think it's 1 1/2" or 2" diameter.
4. Retract boom extension until those 'pins' are resting against the outer boom. (prevents the inner boom from fully retracting)
5. Adjust boom height until the extension is completely level.
6. Lower the crane cable to the ground and it's tension is released. Remove the cable from the pulleys at the pivot end of the crane.
7. Power off and either drain the hydraulic system (oil will be reused) or remove the hoses from the cylinders and plug them with caps/plugs on both the hoses and the cylinders.
8. Take a ratchet strap and hook it onto the crane support pin (on the outer body) and into the hole on the inner extension for it's crane support pin. This will basically lock the crane extension into place.
9. Take a forklift and slide it in between the outer boom and the main body of the cylinder.
10. Knock out the pins.
11. pull the forklift back some. Secure the rear of the cylinder to the fork. Pull back another 3ft and secure the cylinder to the fork there as well. Don't want that cylinder to roll off.
12. Finish removing the cylinder carefully and rebuild it.

 

[tobyS]

I have a 50' stick and have to do this to it (again). I've re-sealed and rebuilt the center section (had a slight bow after 30 years of use). Now I seem to have a broken line or fitting...probably about what you have going on.

It is a PITA. If it is like my crane, and it appears very close (except for my third extension) you need two pieces of equipment. One, like a fork truck to put at the end of the first section, just touching so it takes the weight when out and two, a front end loader or some such piece that can both hold up on the end and pull out on it (then push in when re-assembling), keeping it straight and not binding.

 

[wcuhillbilly]

yeh, looking at it last nite, It will for sure not come out the rear, the cable pulley blocks are welded in from the inside of the tube. I think that with extreme care, I can split the booms and pull the inner with the cyl out of the outer, without having to pull the whole boom assembly. Gonna be tough, but will eventually have to be done.
Good news is that watching it with a flashlite it is not streaming fluid out, just seeping, thus it has taken along time for the fluid to oozz its way down the tube and start falling onto the bed. I can let it go for a while longer, as I need to get the 3rd Jake put on, change the oil, re-engineer the fuel delivery system, and re-engineer the parking brake too..... aside from round up a wet kit for the 10spd and attempt to put that thing in...... Otherwise,,,, the CV/golden driveshaft replacement for the CV shaft from the power divider up to the crane drive is working good.---- see thread "wrecker broken CV Joint" in the 5 ton Hotrodding section.

 

[jhooah]

Mine (M543A2) leaks a small river when I extend it, the **** TM tells of a rectangular hole that you can move the boom out to and then tighten the front sealing nut...well the TM was written by someone not looking at the wrecker in my case.... No hole, no plate covering a hole, no way to access the **** nut. Thought of cutting the bottom plate to make a rectangular hole, but I would hate to compromise any integrity of the boom. Have to eventually break down and pull the boom, but waiting till I have to... I'll use my garage 15K truck lift to steady it, pull the pins and drive the truck forward until the boom is out, then tighten the front nut and reverse the process (Hopefully), and only WHEN I have no other real projects and a level packing of gravel in front of the shop door to drive the truck out level and not start tilting downward as I leave the bay...
Of you find a cheat, let me know.
V/R W. Winget
Virginia

 

[Csm Davis]

Hey brother I have to do this to one of mine and i think I will run mine full out and set my boom supports on the extension and then remove the hoses at the pivot of the boom and the pin on the cylinder nearest the pivot and then slide the extension and cylinder out slowly by holding them stationary and drive the truck slowly forward. The middle of this will be held up by my A frame with my chain fall so when out it can be slowly lowered. Fix it, then basically reverse the process.

Sent from my SM-G930V using Tapatalk

 

[swiss]

Hey brother I have to do this to one of mine and i think I will run mine full out and set my boom supports on the extension and then remove the hoses at the pivot of the boom and the pin on the cylinder nearest the pivot and then slide the extension and cylinder out slowly by holding them stationary and drive the truck slowly forward. The middle of this will be held up by my A frame with my chain fall so when out it can be slowly lowered. Fix it, then basically reverse the process.

Sent from my SM-G930V using Tapatalk

We do want to see pictures of this. Now it makes me want to keep my boom support

 

[73m819]

We do want to see pictures of this. Now it makes me want to keep my boom support

ONLY if you are planing to do this by yourself

 

[wcuhillbilly]

Thanks for the ideas, and input. I had determined to let this one leak some more as I have other issues to look at,,,,, Following Red down a rabbit hole of relocating the hydraulic res down to the passenger side fuel tank location(actually converting the tank to be a hydro res... and moveing the crane hydro pump down to the chassis, installing a rotary manifold in place of the 90* gear box and eliminating the "golden Driveshaft"... the mild seep in the telescope cyl is annoying but ultimately allowable for now...