While I was removing the deck, as detailed above, I found the hydraulic leak.
Even with the deck removed, and better access, I could not drive out either the lower cylinder pin or the left lift deck arm pin, so I wound up cutting out the pins.
As an aside, I tried loosening up the pins with the Bolt Buster induction tool, which is why it looks baked in the photo below. I have mixed feelings about this tool. It does what it is supposed to. It got the pins red hot, without heating up the surrounding areas. However, I have had very limited success with it actually making things come loose. I'd still prefer it to a torch.
Anyway, to cut the pins I used a Ryobi oscillating tool with a carbide blade. It worked, but slowly, and the motor would occasionally shut off, presumably due to heat, so I had to let it cool down. I think if there were access, a pneumatic hacksaw would have been preferred. It did get the job done.
After repeating with the left lift arm, I got the deck lift parts separated.
Now I have to get the motors off so I can recondition the deck.
After removing a bunch of linkage I was able to remove the broom lift arm. However, even after driving out the plug from the shaft cutting, the clamp still wouldn't separate. I'm contemplating re-engineering this part.
After this, I went after the deck area with a needle scaler. I think the mission for today is to clean up and power wash the concrete, so I can mess it up again.
This post goed back a year or so, and gets back to the original purpose of the thread.
One of the nice features of this machine that attracted me to it is that the recovery tank tilts out after it is drained so that it can be pressure washed out.
The vacuum for the scrubber section sits above it in a separate lid.
The lid used two gas struts for counterbalance.
When I first got the scrubber, I had washed the tank and bumped the lid as I put it back. The lift struts were inadequate for the job, and the lid crashed down on my hands, just on the palm side of the knuckles. The good news, I had both my hands there, and the blow was absorbed equally, so that nothing was broken. If I had had just one finger, it would have been crushed, I think. The bad news, I had both my hands there, and they both hurt like heck for a week or so. Moral of the story - don't ignore the lift struts.
The lift struts for the lid are still available, since they are used on the 7760 and 7765 models. The Alto/Lincoln/Advance/Nilfisk part number is 7-76-00104. The struts are mode by Suspa, and their part number is C16-07590.
There are two other lift struts, on the front "hood" of the machine, that gives access to the vacuum motor and filter. In the below photos, I have already replaced the struts and the front hood latch - the black plastic rectangle. The 7760 and 7765 hinge the front compartment at the bottom, so a gas strut is not used.
The ALTO/Lincoln/Advance/Nilfisk part number is 7-76-00105. All the typical sweeper/scrubber websites tell you that it is obsolete and no longer available. Nonsense. It's a lift strut, nothing more. However, I could not read the label for a part number. It was tantalizingly almost visible, but I couldn't make out numbers that corresponded to anything in Suspa's online catalog.
I corresponded with Suspa, telling them as much as I could. They were most helpful, and indicated that they had fufilled an order for struts with Nilfisk that matched the dimensions I had, and matched the numbers I could read. The Suspa part number is C16-07404.
I also decided to replace the wheel and steering cylinder. The wheel didn't want to cooperate, even with a torch, so I had to take the whole assembly out. I didn't have a bigger puller that would get into the groove in the hub, so I used a small 3-arm puller to put pressure on it while I whacked at it from behind. No joy.
It may be hard to believe, but the floor was clean the day before. The ring on the top is a large thrust bearing. It takes the vertical and bending loads, and a smaller bearing on the shaft takes side loads and holds everything together.
The steering assembly was suspended from a plate bolted to 2 c-channels that holds the rack and spur hydraulic steering system.
There was not much evidence of lubrication on either the rack or the spur, although only the gear showed some wear. I don't think I'll replace it.
In theory, there is a zerk, but it is in the channel above the plate and not easy to get to with the machine on the ground. I think I'll put in some lines to allow remote greasing.
The reason I had to replace the cylinder was that the aluminum head had corroded. The rest of it looked to be in good shape once I got the dirt off. No pitting of the rod or corrosion of the main cylinder.
I did learn one lesson (sorry for the blurry picture). I used a racheting box end from gearwrench to loosen the bolts for the plate. However, I failed to transition to an open end until too late. I couldn't get the wrench off the bolt, as it was too close to a plate above, and I could not put the bolt back in, as the gearwrench does not reverse direction. You have to flip it, which obvously wasn't possible. I had to get in with an open end while the gear wrench was still on the bolt.
To get into the area above the steering gear, I had to remove the radiator. It was like this when I bought it, but it wasn't leaking, surprisingly, and I figured I would get it recored when either it started to leak or the engine overheated.
Since I had to take the radiator out, I took it to Brittner's Smoke House (he smokes meats, venison, etc.) and radiator shop for recoring.
I've never had them, but people say the smoked meats are quite good, and I know from experience that they do a great job on recoring radiators. He's the go-to shop for radiators and gas tanks for vintage tractors in the area, and he repaired the radiator for my brothers Bolens G274 a few years ago.
I am done working on machines on any given day when I am sufficiently filthy. Shirt, shoes, face where I wasn't wearing a mask, and hair all looked about like this. Normally I'd wash with the gloves on, then take them off and wash again, but I wanted the contrast to show.
Those brakes were on the original 60 inch and 72 inch self propelled scag mowers with 5 speed peerless transmissions. We had a old machine shop that would replace the the pads and rivets for 5.00. Trick was to lube the springs without getting gook on the pads and rotor I think one of the cub cadet snow blower model has them too. Given the epa/osha refs abestos brakes are a thing of the past