Murphy’s Law

The other day a friend of mine at work dropped by and said that the company that just bought us out, Finmeccanica, publishes a magazine, and that it puts our old company pamphlet to shame.

Today I went to my mail box and picked it up. He wasn’t kidding. Not only does it trump our old pamphlet (which was moderately nice with color pictures and half a dozen pages), it schools all magazines I have ever possessed. 

It is 124 add-free pages of professional publication, printed on high quality semi-gloss paper, stitched through the fold and glue bound. It is even printed in both Italian and English. That’s right, it’s bi-lingual. 

How ridiculous is that?

I work in a building full of people who are supposed to be smart. Now, I know that some of them are not exactly as smart I think they should be to work here, but they should at least be smart enough to handle common instructions. Apparently this is not true.

What tipped me off was the condition of the paper towel dispenser when I walked into the restroom. Earlier today the dispenser ran out of towels, but there was a new roll sitting on the counter. I was of course lazy and just ripped paper off of the roll and left it there. (We do  have people who are paid to replace the paper towels.) A few minutes ago I walked in to find the dispenser open, with the loose end of the roll scrunched up and stuck into a random roller. 

First of all, if you bother to put the roll into the machine, you should at least finish the job. Second of all, there are directions printed right on the back inside of the machine. Thirdly, those directions use pictures and numbers, not even words. I pulled the loose end through the lever arm, and hit the feed button (which could only be improved with a big “press me” label), which fed the paper out, then ripped it off and shut the cover. Honestly, it took me 20 seconds, tops.

Obviously, there is a complete moron still working for us. When I say still, I mean we just fired the guy who got caught looking at porn on his work computer, so it couldn’t have been him. As smart as these people are supposed to be… someone can’t press a button.

After rewiewing my last post, I think the ball bearing idea in the breather is not a good one. The breather should have filter material so that any air sucked into the crank case goes through the filter material. The negaive pressure will help prevent oil leaks in a poorly sealed gasket, however I tried to make sure to properly seat all gaskets, so that should not be an issue. 

In this episode, I will be reviewing the carburetor rebuild and first run. 

The carb on this engine is just about as simple as a carb can get. There is no throttle, only a choke plate and a needle valve. The needle valve is essentially directly exposed in the venturi of the carb, and controls the fuel flow. A check valve at the bottom of the fuel pickup tube ensures that the fuel is always in the tube up to the point where it can be sucked into the venturi on the next intake cycle. 

The reason for not having a throttle plate is that the speed of the engine is controled by a “hit and miss” style governer. This means that every intake cycle is “wide open” and provides maximum power. When the engine hits the governed speed, it simply holds the exhaust valve open and does not intake another cycle until the speed has dropped back down. This is extremely efficient because the carb can be tuned using the needle valve to give the ideal fuel/air ratio. 

This carberuator was missing the needle valve, so a new one had to be made. It was easy to find the thread size and a bolt that fit. I cut the new bolt down and then used a belt grinder to make a “needle” point. This was not accurate enough, and I had to use a lathe to make a better point. For a handle I used a piece of sheet metal cut to match the shape of the handle on the other 1.5 HP JD that my Grandpa has. I welded that to the end of the bolt and then added a stiff spring to keep it from rotating while the engine is running.

After routing the fuel lines to the finished carb, I still had to plug the bottom of the water jacket, and then finish painting everything. (by this time I had put a preliminary coat of paint on just about every part) Once everything was in order I decided to try to run it.

The first run was a shot in the dark. It was all together, and should run, but I had no easy way to test the carb or spark. So the easiest thing was just put gas in and run it! I put oil in the crank case (I had been using oil during assembly up to this point too) and a little bit of gas in the gas tank. I screwed the needle valve down and opened it 2 turns then shut the choke plate. I started cranking and after a few seconds, it actually fired. I couldn’t believe it! I tweaked the carb a little and cranked it again. After a few tries it fired up and ran for a good 20 seconds or so. I didn’t want to run it without water so I shut it off. 

When my Grandpa came back I showed him. I let it run for about 15 seconds and was about to shut it back down but he told me to keep it running and that it won’t hurt it.

The next thing I knew there was a lout pop and the engine lost compression and coasted to a stop. The engine just blew the head gasket. I was actually able to stick my camera into the water hopper and look up the water passage into the head where the gasket was now protruding. This was a little upsetting because I had spent about $6 on that gasket at a mail-order supplier. Luckily my Grandpa had loads of gasket material. (…and yes that is asbestos gasket material! He has the good stuff saved up!)

After cutting out a new head gasket, I put it on using some high temp RTV instead of just a thin coat of oil. This worked great and the engine ran for hours with no gasket failure after this. I am actually greatful that my Grandpa told me to keep running the engine with no water. The head gasket blew because it wasn’t properly sealed. If I had put water in it, it would have seeped into the cylinder and I could have hydrolocked it and that would have been the end of a year of work.

Sooner or later (probably later) I will have to organize my pictures and get the videos of it running on YouTube. Until then, if you want to see a video just ask! Here is a link to the entire gallery of posted John Deere pictures from the restoration. If you want something explained that is not in my posts, just ask!

With the last post I decided to add another page on to this site that includes my Resume. I’ve wanted to put it on here for a while, so there it is!

Yes… 3rd post of the day. Amazing huh? 

The past week at work several people have started to stick out as having extremely valuable specialties. Seeing their expertise, I am starting to recognize my own. 

There are 2 guys who spawned this post. One is a new guy (maybe here a month) who is already doing stress calculations and analysis that is more complicated than I would even consider. Too complicated even for our $30,000 analysis software to do. Yes… that’s thirty with a THOUSAND at the end of it. If I tried to explain what he’s doing, your head would explode. All of this to make sure that a common solder joint doesn’t break.

The other guy is analyzing vibration of circuit boards inside a box supported within another box. He’s making sure that the circuit cards dont shake so hard that they crack. 

Crazy huh?

So what is my specialty? Mechanisms. I seem to be the only guy who can “see” them work before they ever get on to paper. Most people can’t even understand how my stuff works when they see it as a model on the computer…. I’ve even handed my boss a plastic model of something I invented and he couldn’t figure it out. He asked me how it worked and I replied: “magic”. He was not amused.