LW-6 Backhoe rebuild

Yes it's a write off. Cylinder wall is a mess. I've just about finished some severe mods to my LW-6 because there were a number of things I wasn't happy with. Some of the other cylinders have cracked or perished seals so I might as well go through and rekit them all.

The pic above doesn't show it so well but if you look hard you can see a crack running through the green seal. Wondering how many more are like that. It is a 2006 model and had water mixed in the oil when I got it (very cheap). One thing the chinese don't do well are rubber products. Here's how the backhoe hangs after the mods…

I'm not using synthetic but good to know. The BH is 3pt mounted but I shortened the link arms by 200mm so I could cut off the seat and operate the hoe from the dozer. I also welded in a section to join them which stops it from swaying around.

I wasn't happy with the BH for a number of reasons. By far the biggest issue was having all that weight hanging way out off the back end. It upset the balance of the dozer and made it so much longer. Had a lot of difficulty working in tight spaces. The seat wouldn't allow the BH to raise high enough either and it was always bottoming out on the creek crossings. Going downhill would cause the seat to fall forward and bash me in the head. Ouch!

For anyone thinking of replicting these mods, be aware that operating from the dozer seat has a serious safety issue. I have raised the back bar so it can't crush my legs if I accidentally push the outriggers down too far and now it is the perfect height to rest my forearms while operating the controls.

The console is hinged with a strong spring attached to the opposite side so when in the fully raised position it  is forced to fold forward as it makes contact with the back bar. Now there is nothing behind the seat that can shift around and impact the operator during travel.

Shortening the link arms helped reduce the length somewhat but the real issue with the LW-6 is that the inward stroke of the dipper arm is limited by design to almost a 90 degree angle to the boom. I fixed that by slotting and re-enforcing the underside of the boom so it can accomodate full closure.

I then had to cut and reposition the dipper pin otherwise the actuating cylinder would have been prevented from completing it's stroke due to the shaft contacting against the elbow pivot. Likewise the length of the shaft has to be extended by 100mm.

The final addition was a drop pin to hold the boom up when the control levers get snagged by the jungle during travel. I can't test out the hoe until I rekit the cylinders so that will be a few weeks away, however I recently spent an hour doing some blade work as I needed to shift some trees to make a turn-around area for the low loader.

Pleased to report I didn't even notice the BH was on there. No weight/length/movement/grounding issues anymore. It seems to counterbalance the blade very well now and cancels out the bounce of the machine which results in a much smoother cut. 

Digging yourself a hole there Bob! So how long does it take to swap the blade for the loader? I suppose the hoses are all coupling connect?

Bob,  I recall a post of yours somewhere which describes how you gained smoother movement on your backhoe by using washers to slow down flow to the cylinder. I couldn’t find it. Could you please elaborate on what you did? I need to slow down my swing and boom cylinders. What size orifice hole did you end up with? Cheers.

Yes I guess it will be trial and error to determine the orifice size. Also my backhoe hydraulics are plumbed to the main pump on the dozer so it’s performance will be different to the standard PTO pump that most people are using. My intentions are to insert a thin steel washer into the conection between hose and cylinder to slow the flow. If it leaks I will have to fit a teflon washer between the flat face and steel washer. How did you do yours?

Thanks for that Bob. I’ll make them out of copper.