![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
A nice day...
Mar. 15th, 2012 10:35 pm...for a good old-fashioned valve job. Actually it is also a head job but I didn't want some of you to get the wrong ideas. ;)
The weather here has been nothing short of amazing, and it has become time to start working in the yard, especially catching up from the last few years of disabilities. Last weekend Jeff and I cleaned up a corner of the yard, cutting down trees wrecked by winter weather as well as weeds, vines and brush. Trees became firewood, will become mulch soon, and the brush and trash became a large bonfire. The area looks good, but is only partially done. Hey, I'll take results like this any day.
With weather being warm so early, we will attempt that old farmer's ritual of getting the potatoes in the ground on St. Patrick's Day. To that end, I got the big rototiller out and fired it up the other day. Or tried to, unsuccessfully. Seems the carburetor got fouled up and it wouldn't stay running without the choke set. No big deal, I picked up a carb kit and tore into the thing for the first time, having had no prior trouble with it since buying it new in 1990. With gas being as shitty as it is these days, I honestly expected this problem to show up sooner. There was crud in the float bowl and clogged passages. Some time with cleaners, compressed air and some TLC, it was done and good as new. Later that day I got into the garden and scratched up the soil to mix in the leaves I dumped in there from last fall. The tiller was kinda down on power despite the rather easy task it had, so back to the garage for some more checks. As the engine heated up the exhaust would sputter like a Catholic priest being questioned about altar boys. I suspected a burned exhaust valve and put the tiller away until today, when I did a leakdown test to confirm the problem, then I tore into the engine to make things good again.
More of the set is here.
It seems the valves were not burned yet, but the clearances were far too tight and the engine would sputter out the muffler the hotter it got. I did a valve job the same way it has been done since the early days. The valves were in decent shape, they got bead blasted and checked, the seats in the cylinder were checked, and I lapped the valves. Lapping involves smearing an abrasive grease onto the seats and the valve faces, then spinning them together with a tool made for the task. It's not unlike cavemen starting fires by spinning a stick. Lapping matches the valve faces to the seats and creates a perfect seal. I used coarse and fine lapping compounds. Some grinding had to be done to get the clearances right, once everything was set up properly, the head and cylinder gets de-carboned and cleaned, the valvetrain reassembled and checked once more. I need to run out and pick up some gaskets to complete the job, and the old Troy-Bilt will be good for at least another 20 years.
This little project, while unexpected, was not unwelcome. Despite always working on things here at Mayhem Acres, a project sometimes becomes a zen-like exercise in quiet concentration. This was one of those times. The tiller was down on power the last few times I used it, and I knew I was going to need to pay it some attention. Rather than approach this as drudgery, I took the opportunity to dig my little-used specialty tools from the back of the toolboxes, take the time to go through motions that still work on even the most modern engines despite the techniques being a couple hundred years old. I find an odd comfort working on low-tech engines and machinery like this. It's completely hands-on work, problems are found by touch, sight, hearing and smelling. There are no downloading of patches or flashing computers and control modules. A handful of basic tools, some time and nice weather made an otherwise humdrum mechanical exercise into a meditation. I can't wait to get the remaining parts and bring it back to life. Few things for me are as enjoyable as starting up an engine after some major work. Silly as it seems, it's my way of bringing things to life, I guess. And this tiller will get used to start the garden that will provide us with food, as I have been doing for decades.
The weather here has been nothing short of amazing, and it has become time to start working in the yard, especially catching up from the last few years of disabilities. Last weekend Jeff and I cleaned up a corner of the yard, cutting down trees wrecked by winter weather as well as weeds, vines and brush. Trees became firewood, will become mulch soon, and the brush and trash became a large bonfire. The area looks good, but is only partially done. Hey, I'll take results like this any day.
With weather being warm so early, we will attempt that old farmer's ritual of getting the potatoes in the ground on St. Patrick's Day. To that end, I got the big rototiller out and fired it up the other day. Or tried to, unsuccessfully. Seems the carburetor got fouled up and it wouldn't stay running without the choke set. No big deal, I picked up a carb kit and tore into the thing for the first time, having had no prior trouble with it since buying it new in 1990. With gas being as shitty as it is these days, I honestly expected this problem to show up sooner. There was crud in the float bowl and clogged passages. Some time with cleaners, compressed air and some TLC, it was done and good as new. Later that day I got into the garden and scratched up the soil to mix in the leaves I dumped in there from last fall. The tiller was kinda down on power despite the rather easy task it had, so back to the garage for some more checks. As the engine heated up the exhaust would sputter like a Catholic priest being questioned about altar boys. I suspected a burned exhaust valve and put the tiller away until today, when I did a leakdown test to confirm the problem, then I tore into the engine to make things good again.
More of the set is here.
It seems the valves were not burned yet, but the clearances were far too tight and the engine would sputter out the muffler the hotter it got. I did a valve job the same way it has been done since the early days. The valves were in decent shape, they got bead blasted and checked, the seats in the cylinder were checked, and I lapped the valves. Lapping involves smearing an abrasive grease onto the seats and the valve faces, then spinning them together with a tool made for the task. It's not unlike cavemen starting fires by spinning a stick. Lapping matches the valve faces to the seats and creates a perfect seal. I used coarse and fine lapping compounds. Some grinding had to be done to get the clearances right, once everything was set up properly, the head and cylinder gets de-carboned and cleaned, the valvetrain reassembled and checked once more. I need to run out and pick up some gaskets to complete the job, and the old Troy-Bilt will be good for at least another 20 years.
This little project, while unexpected, was not unwelcome. Despite always working on things here at Mayhem Acres, a project sometimes becomes a zen-like exercise in quiet concentration. This was one of those times. The tiller was down on power the last few times I used it, and I knew I was going to need to pay it some attention. Rather than approach this as drudgery, I took the opportunity to dig my little-used specialty tools from the back of the toolboxes, take the time to go through motions that still work on even the most modern engines despite the techniques being a couple hundred years old. I find an odd comfort working on low-tech engines and machinery like this. It's completely hands-on work, problems are found by touch, sight, hearing and smelling. There are no downloading of patches or flashing computers and control modules. A handful of basic tools, some time and nice weather made an otherwise humdrum mechanical exercise into a meditation. I can't wait to get the remaining parts and bring it back to life. Few things for me are as enjoyable as starting up an engine after some major work. Silly as it seems, it's my way of bringing things to life, I guess. And this tiller will get used to start the garden that will provide us with food, as I have been doing for decades.
Tags:
