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I picked this old guy up for about twenty dollars. I looked at it and it looked to be in sort of bad shape, but the drive assembly just fascinated me. I figured it was worth 20 just to get a good look at how it worked. We've already tried to pull it a couple of times and it's backfiring badly through the carburetor.
Now when I first heard it backfire, I thought it was odd and I thought maybe it's not a carburetor, it could be something internal. Then I realized after pulling it a couple of times that the backfire had a rhythm to it. So the next thing we're going to do is pull the front cover off because I'm betting it's got a valve that probably dropped.
The valve is dropped, it's wrecked the piston, and we're done. There's just not enough value here to make it worth taking the piston out of it. So let's have a seat at this.
This is the only thing we've done to this outside of cleanup and oil spill that it had on the side. This is our first look inside, so if it's a bundle of parts then we're pretty much done with it, huh? At first look, everything looks like it's in one piece. The springs aren't very tight on these.
Oh, we've got an extremely loose rocker arm on this that would cause odd backfire. And if we look in the pan, that would be the guide for this. So we may have found the problem already. We'll put that back in and see if it makes a difference at all.
Since the pan comes off pretty easy, we don't mind going back and forth a few times. You can see it just sits on top of the spring here and it's held in place by this. So this nut may have come a little loose over the years and had it shake out. Certainly hoping there's no internal damage because when I bought this, I was thinking that the mower is newer than the deck, so I can sell the mower if nothing else.
Okay, so when you adjust these, super super easy adjustment. You want just the tiniest little bit of play, but you can turn the blade to make sure that they're all the way top and watch them run. As you can see, the upper one is pushing in. Now we'll back it out again and now we know that they're both all the way up. And it looks like we had a pretty good guess when I just wrenched it on.
Let's see, a little loose, a little tighter. Okay, right about there, it's got some wiggle. One doesn't look like it had any problems to start with. We want to let him have just the tiniest little bit of wiggle. A sixteenth of a turn could make the difference between rattling and keeping a valve open.
Yeah, if I you run them, everything appears okay. And make sure you see your push rods are seated up correctly.
So now we're going to go ahead and put the cover back on and prime her up with some starter fluid and see what we've got. It does seem like the rocker coming off shouldn't do any internal damage to the engine, but you just don't know because you've got to keep in mind god knows how many times they pulled this before I came along trying to get it to start that way.
Now if this works, then this motor was easy money. And again, if it's got internal damage beyond that, then we'll pull the carburetor and air filter cover and gas cap and call it done. Okay, let's give her a run.
Crammed a whole lot. This thing may not have run for the last two years. So a mower that we bought only because we were fascinated with the drive gearing and how it works turned out the only problem it had was a rocker shaking itself loose in the motor. Hmm, it doesn't happen like that very often. Usually we have to spend a lot more time working on one of these before we get it running.
