1983 hackjob build thread

Durtymax

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If anyone is interested in seeing an amature bite off more than they can chew, you should enjoy watching this project unfold.

This was a week or two ago.
20180928_181132.jpg


Didn't run but it turned freely. Trying to start it just resulted in gas being dumped all over. After messing with the floats, I got it running good enough.

And here we are today
20181012_173537.jpg

Theres a hardtail from tc bros on the way, so that'll be step one I suppose.

I'm looking forward to keeping everyone updated.
 
Alright,
I am going to need lots of help and advice throughout this project. Things are looking a little bleak. I had a hunch it was burning oil, because there was so little in there when I got it and the spark plug on the rh side turned completely black after about 10 minutes of running.
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The first thing I noticed was metal shavings in the oil after I drained it. As well as in the filter.
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I started with the easy stuff, and got the side covers off. Now, I think that that the oblong piece on the end of the kickstarted mechanism (shown)
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smacked a bit to hard into the case and did broke the edge. I picked at it with my fingernail and some came off.
20181014_124625.jpg

The kick start was working, but I'm not too sure what to do about this.

Now, to tackle the oil burning problem. Being that I've never torn down an engine before, I simply started at the top.
20181014_131827.jpg
 
And this is when I confirmed the burning of oil.
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The head gasket was doing exactly nothing. Also notice the cam chain guide is missing the part that contacts the chain.
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looks like the rings are bad too.
20181014_144727.jpg

Now the question is, do I crack the lower part open to see just how bad things are.
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Before you decide to split the cases, pull the sump plate and lets see how much metal is in there. The bottom end can be flushed without disassembly... providing the tranny worked OK before you tore it down? There's procedures in the manual for checking the connecting rods without splitting the cases.

So far I don't see anything in your pics that are out of the ordinary for a tired XS. Rings, cam chain and guide... give some good pics of the cylinder bores.
 
I pulled the sump plate and filter, it was torn but there really wasn't any metal in it. The round oil filter seems to have caught most of it.
The tranny worked before, so maybe I am getting ahead of myself, about splitting the cases. I just don't want to have to comeback in 2 months and work backwards.
I'll get some pictures up of the bore later today.

Now here is a question:
When I pulled the valve cover, 3 of the sleeves with red o-rings came out with no problem; but one is stuck in the cover. Is there a good trick to get it out, or since it is tight in there should I just go heavy with gasket sealer during reassembly and hope it doesn't leak?
 
Thanks, I gave it a few good whacks yesterday with an 8mm socket as a punch. I just wanted to check before I hit it any harder.
 
You don't really have to take those sleeves out, unless you're planning on removing the rockers from the cover. And there's no reason to remove the rockers really, unless one is visibly worn out and bad.
 
The O-ring on those sleeves are there because it sits in an oil pressure cavity. Granted it's pretty low pressure... and granted that the O-ring will probably be OK. Speaking for myself though, I wouldn't leave an old seal inside a top end I had apart if it was a seal that required pulling the engine back out and tearing the head back apart on the odd chance it did leak. That's a lot of work that could be prevented now instead of later. Again. speaking for myself, 'probably OK', ain't good enough.
 
I just hit it a little harder and it popped right out.
These rockers don't seem too bad... then again what do I know.
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What about these cylinders, should I just try honing them?
15396358964335400114993277446589.jpg
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And last question, what does the 001 on the outside of the cylinder mean?
Thanks
 
And last question, what does the 001 on the outside of the cylinder mean?
It's the mm past 75 it was originally bored to. At this point it might be moot. In the last pic.... that scoring looks like it might need a re-bore. It's hard to tell from a pic.... does your fingernail catch on those?

15396359722951792324317489403574.jpg
 
The "001" on the cylinder sleeve is the fractional portion of the bore size as it was new, as in 75.XXX mm (the "001" replaces the 3 X's). When you get the piston tops cleaned off, you will find a 3 digit number stamped there too. That would be the fractional portion of the original piston size (when new), as in 74.XXX mm. One subtracted from the other gives you the original piston to cylinder clearance. The "new" spec is .050-.055mm. You have to measure the parts now and see how much clearance there is because of wear. The piston usually wears first and more because it's soft alloy compared to the cylinder bore's steel. A "quick and dirty" check can be done by inserting the clean piston back in the bore without the rings on it and seeing how big of a feeler gauge blade you can jam down between the two. If you can get one bigger than .004" in there, the wear is bad.
 
Well it doesnt take a feeler gauge to see that this is well over 4 thou. Calipers read 74.39, thats a far cry from 74.949.
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Well that sucks.
 
Lots of good info in there, you guys all make this look so easy.
I was trying my hand at some soda blasting today, and I uncovered some concerning areas in the heads. Just under each intake valve is a large area that doesn't look right... I'm not sure what I would call it, but here is a picture of one of them.
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