Little update:
Never did find the right manual for it.
Found out it was made in 1970.
Used the trencher to level the site for our above ground pool last summer, then didn't use it again till a couple of weeks ago. Expanded the area of level ground for a newer, larger above ground pool this year, and leveled some spots for some small sheds. Worked fine for everything I used it for, except that the dang battery kept dying between uses. Will use it to run power out to the new sheds and the current shed later this summer, probably.
Then a co-worker of my dad needed to borrow it to trench 600 feet. Luckily he and his dad run a small engine repair shop, because it needed a lot more work than I thought it did.
The oil in the pan wouldn't even come out the drain hole when he unscrewed it. He had to stick a screwdriver into the hole to poke a hole in the junk in the bottom of the oil pan. One of the hydraulic hoses broke. Oil bath air cleaner was really fully of junk. Carburetor (it appeared new) was full of junk. The control lever on the lower right bottom of the dash was stuck. I remember a control lever/knob that we couldn't move. He took it apart, cleaned it up, oiled it and guess what-it now works and controls the speed when trenching. They greased all the fittings. He said it used a LOT of gas, but not much oil. He didn't smell gas in the oil which is very good. He said it didn't look like the machine had a lot of hours of use on it. It should last a lifetime. The points looked new. He hasn't tried to find out why the battery goes down. He thinks it is the voltage regulator but didn't have time to check it out.
He said he trenched about 500 ft out of the 600 he needed to trench. It did great. He was digging about 30" deep in wet black clay. He has ordered a new oil filter and will install that and change the oil again this week. They drained most of the hydraulic fluid and replaced it-it was murky looking which means it had water in it. They also changed the hydraulic filter.
So I'm pretty happy to have lent it to him as now I'm getting back a trencher in tip top shape!
Wonder if he needs to borrow a 1976 Ford F-150?
