You can go to the Briggs site and download a parts manual. Hopefully this link will work. The engine I came up with doing a quick web search is- 91202-1017 It should be PN 494559 Here is a link that might be useful: Link

I believe the nut size is 15/16. I used to own Tru-Cuts when I lived in Los Angeles, but now I only have an old Cooper Klipper front throw which I keep for nostalgia reasons. The Cooper uses 15/16 jam and regular nuts. I ended up buying a 15/16 x 1" wrench and grinding the flats down to about 1/4" or so. To adjust, start with the reel drive first and break the large nut free of the jam nut using either a tappet wrench or modified regular wrench. Tighten the main nut until the clutch begins to engage about half way down on the control rod. The tighten the jam nut against the main nut. You don't need to fully tighten the jam nut because you'll nee to go back and check the adjustment and possible re-do several time. Correct adjustment is tight enough to fully engage the reel without slippage, and able to go past the detent to stay engaged, yet loose enough that there is no drag or creep when disengaged. Then go the the rear drive clutch (in the center) and do the same thing. Most professionals would set the drive clutch to engage with thumb pressure but not go far enough to go past the detent and stay fully engaged. Again you want it loose enough when not engaged to prevent creeping. You may have to check and adjust several times going from reel to drive and back again. This is because the two clutches are on a common shaft and tend to affect one another. However, the reel clutch has less effect on the drive clutch, so you want to start with drive clutch. Once you think you have everything right, tighten down both jam nuts against their respective heavy nuts and check one more time as things may have changed slightly. Two places sell tappet style wrenches in 15/16 x 1". Snap-On is the best but very expensive. The Thin Wrench is much cheaper and should do the job: http://buy1.snapon.com/catalog/item.asp?item_ID=633544&group_ID=675024 http://www.thinwrench.info/51-15-16-x-1-double-open-end-wrench.html

Did you buy this from a local dealer or thru internet? If local, I cannot believe dealer didn't set the mower up and check blade and bedknife adjustment. If you have to do it yourself, you'd be wise to get a spanner wrench for adjusting the bearing caps. You can use a drift punch (I've done it myself) but as in the rest of life, the right tool is the best tool. When adjusted properly, each reel blade (all five or seven) should be able to cut strips of paper along it's entire length every four or five inches. With a seven blade reel, that means you are going to be checking cut at 35 to 40 locations. BTW, the mower will tend to throw grass to one side, due to the spiral of the reel. When I mow, I'll fill catcher about half, push a handful of grass over to the empty side, and then continue mowing until full. Only takes an extra few seconds.

Am I correct in assuming you are talking about slack in the chain from the engine sprocket to the clutch pack sprocket? If so, you can take out some of the slack by loosening the engine mounting bolts and sliding the engine back, away from the clutch. The mounting holes in the mower base are slotted, permitting some fore and aft movement. If you have even more chain and sprocket wear to take up, you'll need to get a "half link" or "offset link". ANSI roller chain has a pair of rollers joined by a set of links, so if you remove one pair, you lose two links. An "offset" or "half link" allows you to make the chain shorter by a single link. If you're lucky, there is already a "half link" in the chain. Then you simply remove the "half link" and take up the remaining slack using the slotted holes. The "half link" is installed with a cotter pin, which is easy, but you'll need a chain breaker to remove a full link. Chain breaker should be available from a motorcycle shop or a Harbor Freight. Should cost about $20. Your 25" Tru-Cut should use ANSI #40 which is 1/2" pitch. Smaller Tru-Cut such as 21" use #41 which is also 1/2" pitch, but slightly lighter construction.