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Reviving a barn found engine

1946 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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There's a bike for sale with a hundred miles for $120

Shoot, if something like that was anywhere near me I'd jump right on it.

Ditto.A $120 CX/GL in any state if complete-ish is worth $300+ at least in spares and savings

I've hardly paid anything for parts for the past 3 years because of buying Ebay stuff nobody wanted like basket case engines and one lucky deal of a complete CX in bits with a 2nd engine(also crapped out but full of spares).

I'll probably never need a gearbox/clutch or a starter motor/Radiator etc
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The engine could do with flushing.Any metal particles/debris left in from the Cam chain chewing can get under the big-end shells.This is the single most common cause of the early demise of these engines.

I use a car power washer and a good half hour blowing through all the oil orifices.I Use the washer on the rear case/stator but gently with the fan setting,not jet.You'll need the front case off as well to clean the sump and remove the oil pump and strip and cleaned it.They aren't complicated,just watch out for the O-rings and dowels and the small pin you must remove when taking the pump apart.Again blast through with car pressure washer or compressed air if you have it.

If you/we are lucky we can get all the debris out of the engine.Make this the priority as it only has to be done once and right and then when re-constructed may not be an issue for tens of thousands of miles.Done wrong and the engine can go within a couple of hundred miles.BTSTGTTS

You probably won't like the next bit but it's up to you.In my case I would strip down to the crank and check the big-end shells but then it's time and cost and do you feel lucky?

If unsure at any point post/PM.
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