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Reviving a barn found engine

1945 Views 17 Replies 10 Participants Last post by  bear351c
OK, so I pulled my spare engine out of my garage, and it was much uglier than I remembered. Lots of oxidized aluminum, very dirty, and rust on every fastener. Wow, it sure looked better in my head!

So, I started cleaning it up, dropped the radiator and drained the coolant (only a little was left in there), and got my first hint that this was going to be... different. I bought the engine around the same time as the bike, so I didn't know much of anything about our bikes at the time.

I went to open the radiator drain plug, but there wasn't one. Just a smear of epoxy or something like that. Like I said, first clue. I continued to clean up, pulled the valve covers (one has a hairline crack that was patched with RTV sealant, second clue) and spark plugs. I then turned the engine over a few times-- first good news, not seized!

Next up I was going to adjust the cam chain tension, but take a look at the picture-- what is missing there, instead only a smear of epoxy/goo? My cam chain tensioner bolt!

So, OK, what do I do now? The engine on my bike had some sort of full fledged coolant/oil combination due to my stupidity. Should I resign myself to cracking both of these open and hope I have enough for a good bike? Or just adjust the valves on this thing, install and take a listen? Why would someone do this???

Or look for another engine? There's a bike for sale with a hundred miles for $120, but I should not really be spending that right now. I'm at the too many projects stage right now, with twin 17 year old daughters cars being a 1078 Volvo and 1974 Bug, both of which have many needs. I just want to be able to ride!
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I opened the rear cover this afternoon. Shep, the impeller area was in very ugly shape. I shudder to think what the thermostat looks like.


I cleaned up the valve covers yesterday with a wire wheel, otherwise there she is.

Gruesome. Hard to believe it still turned. I was able to get the impeller off, and it actually cleaned up ok, but a little pitted from all the corrosion.

Cam chain. Adjuster looks to be about as far up as it can get.

A closer look at the adjuster bolt.

Chainsaw action-- The damage. There were a few bits of bright shiny aluminum in the case here and there.

Ran out of time and didn't pull the flywheel, didn't seem to be much point anyway. Starter clutch holes looked ok, not ovaled anyway.

I priced cam chains and tensioners at my local dealer-- about $100 for the chain and $50-60 for the tensioner. Is this typical?? I figured they'd be cheaper for some reason.

So... I'll be pulling the engine out of my bike and looking at it. I drained the oil from it last weekend and discovered a disgusting milk shake-- head gasket, mechanical seal? (also possible starter clutch probs.)

So there you go, not as exciting as one would hope, definitely not as good as I'd hoped (was hoping for an auto tensioner...)
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The cam chain bolt was actually tight, so that's something I guess. There was a a little bit of adjustment left, but not much at all.
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