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Discussion Starter · #1 ·
Took the heads off my new 'Baby'. Can some of the high end, inside the engine kind of guys, weigh in an make recommendations? Other than changing the block, I would suspect at a minimum I need to pull the pistons and resurface the cylinders. Is this recoverable?



Here is a look in the cylinder: Inside Left Cylinder
 

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With all the rust you pulled out I would say the cylinders are badly pitted to the point honing them for new rings won't do much good. Boring doesn't seem to be an option either since over sized pistons and rings are very rare even on eBay. The rust will have pitted the valves and seats as well. That in itself can be costly to have a proper valve job done to get them to seal again.

My vote is to find another motor. It's be a lot quicker and less costly.
 

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Recoverable?

Yes - at a price, a price which`ll be way over the cost of a good secondhand engine i would think..



Looks like the cylinder is FUBAR.

Way past a simple `glazebust`!

That`d need to be rebored, with oversize pistons and rings - if you could source any, that is.

What are the valve seats like?

They`ll probably be corroded and need cutting. Poss new valves if they`re too far gone.

Add on gaskets, seals, other unexpected parts etc, etc...

Nah, not worth it.



*edit*

LRXCD got in there first - must learn to type quicker...
 

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Hard to tell by just looking at the video. Was the engine left without the heads on ? (where did the liquid come from).



I doesnt look good, but the only way you will know for sure is to clean out the cylinder so you can see the sides. I would put the piston at the bottom of travel and clean all the gunk out. This way you can look at the cylinder and see if the sleeve is damaged bejond repair. Look for deep scratches and rast pit holes.



While the "gunk" that came out looks nasty, it depends on where it came from. Obviously there was a crap load of carbon in there, but knowing "what" is there and "how" it got there can make a big difference. Example, if the engine was placed outside with the heads off (or plug out or rocker cover off) and sat gathering rain and crud, the cylinders may be ok (depending on the time it sat like that). For a short period the oil film on the walls would help prevent major damage and free up stck carbon. If it say too long, the cylinders may still be good but the bottom end may be screwed if a lot of water got in.



Anyway, if it were me I would clean out the portion of the cylinder I can see and make the call from there. No point spending any time or money on it unless the answers to the questions above are favorable. Clean it out and send another video and maybe others can also give there opinions.
 

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Discussion Starter · #5 ·
The liquid is Marvelous Mystery Oil the PO had placed through the plug holes to 'loosen' the engine up after 18 years of sitting in his shed. I think the crusty material is rust. Seems Georgia humidity got in via the exhaust. I will clean up as much as possible and repost video. Agree it is very bad, but what a learning opportunity it is to get acquainted with these old bikes.



Thanks for all the responses. It is my 'spare', 'can I bring her back to life' bike so time of not of the essence.
 

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The liquid is Marvelous Mystery Oil the PO had placed through the plug holes to 'loosen' the engine up after 18 years of sitting in his shed. I think the crusty material is rust. Seems Georgia humidity got in via the exhaust. I will clean up as much as possible and repost video. Agree it is very bad, but what a learning opportunity it is to get acquainted with these old bikes.



Thanks for all the responses. It is my 'spare', 'can I bring her back to life' bike so time of not of the essence.


This is basically what I have done over the years.I used a parts bike to keep my main CX500 on the road and then built another from spares,my present ride.This allowed to to get to understand the deeper inner workings of the engines.



What condition is the engine oil in?
 

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Well, if that fluid is mystery oil placed in it to keep it healthy, the cylinders may not be that bad. I would say clean it us best you can to get a good look at the state of the cylinders. With the mystery oil in there, it may have kept a coating on things and prevented any corosion. My bike was stuck in a garage for almost 30 years, and the cylinders were new looking (only had about 16,000 miles on it) and within original manufacturers specs when I micrometered the inside diameter.



If the cylinders are good, chances are the valve seats can be lapped and cleaned up (did that on mine) and as long as the oil looks reasonable you may have an OK engine. I would at this point check that you can turn it over with a wrench on the front chaft bolt, and if so check what ever oil is left in it (look for water).



If it checks out ok I would put the heads back on and try to start it. Electrically cranking it over you should be able to hear anything "off normal", if not see if you can fire it. If there is any major damage you will probably find out, but more than likely its just crud from sitting.



You could strip it right down, but thats a lot of work for something that is an unknown. If it cranks smooth and even starts that would indicate it may be worth rebuilding. If it sounds like there is a broken rod, then its not worth even pulling it apart unless your using it for parts.



From what I have seen in my limited time with this bike, it can look like its nothing more than scrap metal, but can fire up and run will with a little maintenance
 

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Hummm....don't normally see so much gunk in an engine. With that much carbon looking material on your head, it suggests that very bad gasoline was used, and/or oil was getting into the cylinder - probably both. So that suggests you will either need to strip the engine completely down and pull out the pistons and check the rings and cylinder walls, bearings, connecting rods too, as well has look at the valves - from the air flow side - and see what they all look like. Until you do this, you'll never really know. If time is on your side, do a little bit each week.
 

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custom pistons from wiseco arent too bad usually. send them a piston, tell then thats what you want in one-size up overbore, all is well. but, a second motor would be cheaper than boring and new pistons.



but, dont throw the old block away....someday, the block will be highly valuable still at a "first bore" state
 

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Discussion Starter · #10 ·
Here are some updated pictures of the internals of the engine.



Right cylinder:







Left cylinder (the same cylinder as depicted in the video above):







Right head:









This is the first time I have been inside one of these engines, or any engine since small engine repair class in high school 35 years ago, but the valves look pretty bad to me for a bike with 9000 miles on it. Overall, the right cylinder does not look near as bad as the left. Left will likely clean up some more. Using solvents etc before 'getting physical with it'. I am going to tinker with it for a week or so, then make the decision on engine replacement, or not.
 

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The cylinder walls look like they've probably had the gun, a quick hone would give you a better idea of their true condition.



The heads MAY be usable, removal of the valves and maybe a quick attempt to regrind a couple will show their true condition but it looks like you'll be in the market for another block at the very least.
 

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Well they sure look nasty, but a lot of the nastiness is the gunk. I think to make any decision you should try to get all the crud off and see what the bare metal tells you.
 

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Unless you want to try and find sleeves that fit and are willing to either learn how to do it or pay big $ I think that block is a very heavy paper weight.

I am so sorry about that. It is very disappointing to see. I thought that engine was going to look pristine inside.

The guy stored it inside his shed all that time and did not leave it in his yard like so many of these people do.
 

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Discussion Starter · #14 ·
This is basically what I have done over the years.I used a parts bike to keep my main CX500 on the road and then built another from spares,my present ride.This allowed to to get to understand the deeper inner workings of the engines.



What condition is the engine oil in?


PO told me the oil 'looked good' when drained. Not sure what 'looked good' would be after 18 years parked.
 

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Discussion Starter · #15 ·
Is there a 'best' solvent for the carbon? I have pretty much removed all the rust looking material now.
 

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Discussion Starter · #18 ·
Well, I have been working with a product named "Evapo-Rust". I guess it is a CLR type chemical. Yesterday, I soaked it, then rubbed at the carbonic build up with a toothbrush while it was immersed in the solution. Removed the fluid and 'trash'. THen soaked it for 24 hours in the solution. Look at the results. Maybe this can be salvaged after all.



 

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The problem I would have in my mind is the damage to the bores which cannot be seen with the naked eye.I would be getting proper expert advice should be sort from an engine/engineering specialist.There's also the damage that will almost certainly been done to the piston rings/oil ring/s.



You would need new rings at least I suspect and by the time you buy them and other parts another running engine may be a a better bet?
 
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