OK, let's start at the top. First, I admit a dumb mistake, so let's get that clear at the beginning. So, hanging my head in shame, tail between legs, let me get on with the problem. The punch line: I need help with a broken timing gear. A friend of mine spoke to me last Fall. He bought a pressure washer, albeit a small one, not of good quality, but thought to be adequate for his homeowner tasks. It is powered by a Honda GCV160 engine, pressure rating of about 2,500 psi, with flow of about 2.5 gpm. These specs may not be quite right, but you get the idea of the size of unit. He said the pump was broken. He asked if I thought a new pump could be found and mounted. I did some online research, and found one that was intended for a one-for-one replacement for the specific model. However, he did not make a decision about the problem. In early March, he asked me again what I thought. In the end, we decided for me to get the pump, and I would get it installed. He is an outstanding cabinet maker (retired for many years now), but mechanically, he doesn't do so well. The job looked pretty simple and straight forward. I ordered the pump, and, after some delay, arrived. Last weekend, I got his washer unit, and put it up on a table in my driveway (plywood sheet on horses). I unbolted the old pump. That meant the engine was completely loose from the unit. Three bolts fastened the pump, through the frame, and screwed into the engine base. There were no other connections (e.g. low pressure sensor). The pump is a direct drive, through a keyed shaft out of the engine. Perhaps this is how they are all done -- only one I've spent time tearing apart to some extent. With the engine loose, and my single-handed attempt to get the new pump positioned in the right place, get bolts through the frame, and started in the engine base, I quickly found I was short a hand or two. Many failed attempts happened, and the engine was not tied down. The inevitable happened -- the engine fell off my table (told you "dumb mistake"). After more work, I finally got the three bolts through the pump, through the frame, and screwed into the threaded holes in the engine base. In reality, the replacement should have taken all of 20 minutes, but I wrestled with it more than one hour. When the engine fell off, I did a quick examination. I feared the gas tank was the most vulnerable. In checking for damage to the tank, I found none. Also, the exposed stub shaft was vulnerable, but no damage to it either. I did notice that the OVC cover on the front had a ding in it -- just cosmetic damage to the cover. I got it all hooked up the water, wand hose, etc, and tried to fire it up. No success in getting it started. The owners assured he he had run it late last Fall with no problem. After some doing, I found nothing wrong. The spark plug looked good, but when looking for an arc across the electrode of the plug when grounded, and pulling the cord on the engine -- no arcing across the electrode. This means no spark. Why? My only conclusion was a bad ignition module. Why would the drop of the engine cause a bad ignition module? I did some research, and found one online. Also, I found a local dealer with one (didn't realize there could be so many choices in modules for a very common Honda engine). Apparently, the module is somewhat unique because of the shutoff switch connected to the module. I'm not sure how the GCV160 is used on the consumer lawn mowers. I did an online search through parts manuals, but did not find the family number of the specific engine in question. Why? I wish I knew. I took the module number directly off the one mounted on the machine, not a parts manual. I found a dealer with an ignition module late this afternoon. I wanted to replace the dinged up OHC cover, so I took it off. When I opened up the cover, I quickly discovered I had more than just cosmetic damage. The timing gear had a piece broken off, the timing belt was off the cogged gear. When the cover got hit (on the drop off the table), the cover indentation hit the gear, causing the damage, and shoving off the belt. Ouch! This started out as a pretty insignificant project, and now I have a damaged engine, and am unsure how to fix. Obviously, I owe the owner his washer back in his garage, in working order. But, I now have a damaged engine that I'm unsure I can fix (many mechanics in the audience probably would consider this small stuff). Do I buy a replacement engine? Do I buy him a new pressure washer? I see two issues. How to replace the gear? And, how to get the gear timed on the timing belt properly? Here are some images. I may need another post to get them all included. I'm looking for some guidance on a couple of levels. 1. Why can't I find the parts manual online? I see a family number: 3HNXS-1871AK. 2. Is getting the old gear out difficult? I see a protrusion on the bottom, but am not sure how it is important for the gear. It is at the pivot point of the bottom gear. 3. Is there a repair manual online to give me guidance on how to get the timing belt mounted properly with regard to synch of the crank? The gear has lobes on it for activating the valves. Anybody with some thoughts about helping me out of my stupidity? Thanks.