[jlbutler81]

tl:dr How concerned should I be about the sludgy oily head bolt? Would it be just sludgy from sitting for years? EDIT: Both the heads' top foward most bolt on each side were the same thick oil, maybe this is normal for this engine to have oil sitting there? It might just be the end of the oilway and if it doesn't run it just sits in the bolt hole.



I am disassembling and inspecting my CX650 motor for a potential transplant to a 500 frame. Since I'm new here I'm not entirely sure where to put CX650 non-turbo posts so if this is the wrong place let me know.

I understand there's an oil way between the top two head bolts and when I pulled the top right bolt of the right cylinder there is a very thick oily residue. I was wondering how concerned I might be about this and if there would be any suggestion as to how I might wash out the bolt hole and if the oil ways need to be flushed. I'm wondering if something got clogged and the oil was baked. The history on this engine is unknown, it does turn freely and bike had 9k miles on it. Inspection stickers from 1999; last road use unknown though. I was told it was recently bump started and I'm almost positive that was a lie. The carbs were actually pretty clean but bone dry. The thermostat housing was completely clogged and crystalized but fresh-looking coolant came out of the radiator and heads. I think someone was tinkering with it, saw the radiator had no coolant in it and just added fresh coolant.

I know the meth heads I bought it from probably tried starting it; they tried replacing the starter and I think with the wrong one but it does actually fit into the starter hole but is a SM-8 starter not the SM-228 I see listed for these CX bikes. The starter clutch gear on the inside appears fine and undamaged but I plan on checking the starter clutch out as I take it apart.

Free meth found in the thermostat housing:

Tstat Housing before disassembly:

The oily sludgy head bolt: (just leaned against block for picture, that's not the hole it came out of)

 

[Jah Rider]

Remove the sump and have a look, if you have sludgy oil there is a fair chance the big end bearings/crankpin have suffered from low oil pick-up volume by the oil pump - a common event on a 650 and one that will render the engine either very difficult/expensive to repair due to lack of new crank bearings..

 

[jlbutler81]

Remove the sump and have a look, if you have sludgy oil there is a fair chance the big end bearings/crankpin have suffered from low oil pick-up volume by the oil pump - a common event on a 650 and one that will render the engine either very difficult/expensive to repair due to lack of new crank bearings..

I'll take a peek and I watched the motofaction test for checking that bearing.

Edit: this test, it passed easily. rotates very easily so I'm hoping that's good news

Also found a post on the aussie forums about using the XL1000 Varadero bearings that require a little dremeling to fit the CX650.

https://australiancx.asn.au/forum/index.php?topic=2522.0

 

[Jah Rider]

That clunk test will only tell you that the big ends have suffered terminal, catastrophic and unrecoverable failure, there`s no substitute for a visual inspection and if necessary measurement with Plastigauge to confirm the oil gap clearance is within spec.
It all depends on the engines history though, 650`s do not take sloppy maintenance well, any evidence of lack of oil changes such as what you have alluded to with your suspicious sludgy oil does not bode well if you haven`t heard the engine run.
I expect it`ll be just fine if that low mileage is true..

 

[CXPHREAK]

And you don't know the maintenance history as Jah says.

Not just the quantity but the quality.

A worse case scenario is this.

Needs a cam chain and the chain has chewed into the crank carrier bolt.

This actually finds its way through the oil pickup to the pump, scores the pump rotors reducing the pumps efficiency and lowers oil pressure.

Then the new oil filter is fitted by some bonehead at the next oil change with the spring on the wrong side of the filter, missing spring, whatever.

The motor now has no filtration and those crank and rod bearings are now mainlining fragments of hardened steel.

Personally, I'd want to see for myself.

 

[jlbutler81]

And you don't know the maintenance history as Jah says.

Personally, I'd want to see for myself.

So would the consensus be a complete tear down to the crank? I'm not opposed to that idea, I do love engine work.

She turns by hand so smoothly and without the slightest hint of resistance or noise though. Taking it apart is free, putting it back together will be expensive

A little water had gotten into one cylinder (either coolant head leak from sitting or no spark plug/rain I couldn't tell) and there's a survivable amount of corrosion at the top of the cylinder so I was thinking to pull the pistons anyway to inspect the rings to make sure they're not stuck.


I did make the cam chain post, but here's some pics just to keep this thread in some order. This chain will get replaced.

 

[CXPHREAK]

I would at least pull the rods.

Then you see the rod bearings. Generally if they are good so are the mains and you'd be able to free spin the crank to see how smooth it is.

Keep the rod bearings with their respective rods and caps if they're viable so they go back the same way they came out as they will be mated to the crank in this position.

Freeing the rings {if needed} would also be a good reason to pull the pistons.

 

[jlbutler81]

Here are the Stator pics, I know I've read that people like to replace them in cases of how burnt they look but I don't have a reference for how burnt they should not look.

 

[CXPHREAK]

It's a bit dark. Given that it's a G8 I would replace it with a caltric. They are Chinese and quite cheap but I and others have fitted a fair number now and found them good. You may need to move the ground connection as it can interfere with mounting to the rear cover.

Here's one on Oz ebay. These are what I use and believe are the same as those sold under the caltric name. Ebay should suggest something more suitable to your location.

Magneto Engine Generator Stator Coil fit Honda CX500 Custom 1982 CX650 SV1000S | eBay

Find many great new & used options and get the best deals for Magneto Engine Generator Stator Coil fit Honda CX500 Custom 1982 CX650 SV1000S at the best online prices at eBay!

www.ebay.com.au

 

[jlbutler81]

It's a bit dark. Given that it's a G8 I would replace it with a caltric. They are Chinese and quite cheap but I and others have fitted a fair number now and found them good. You may need to move the ground connection as it can interfere with mounting to the rear cover.

For $40 on Amazon? I'd have no problem swapping it out.

Sold by Caltric so I'm assuming authentic:

Amazon.com: Caltric Stator Compatible With Honda Cx650 Cx650C Cx650T Turbo 1983 : Automotive

Buy Caltric Stator Compatible With Honda Cx650 Cx650C Cx650T Turbo 1983: Stators - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

www.amazon.com

 

[jlbutler81]

Pushing further into this poor motor. To be fair though, I'm not seeing signs of catastrophic damage. Some light tiny pieces of metal but nothing I haven't seen in any other motor. Pistons are coming out...eventually.

Oil pan: removed because someone butchered the drain plug:

Bottom of crankcase, the void in the sludge is where I wiped my finger. The glittery bits aren't all metal; the light makes them shinier than they are.

I'm assuming someone was doing something stupid to this bolt:

Oil filter screen:

 

[jlbutler81]

Pistons are out and I think they're alright. Did have a semi-stuck ring or two but they moved with a little encouragement.


Opinions on the journals and bearings? @CXPHREAK

2nd

crank

crank feels super smooth turning around on it's own

They must have had piranha projecting them rods -_-

Sensitive content, not recommended for those under 18

Show Content

 

[CXPHREAK]

Without having those bearings and journals in my hands they look good on my PC screen.

Any concerns and you could plastigauge them.

But it looks like you've scored a good one.

 

[Randall-in-Mpls]

I'm assuming someone was doing something stupid to this bolt:

View attachment 211206

12-point 3/4" socket?

 

[CXPHREAK]

At least it wasn't a cold chisel....

 

[Randall-in-Mpls]

They must have had piranha projecting them rods -_-


View attachment 211223

Remember, you aren't really working 'til you bleed a little.

 

[Jah Rider]

It looks like you may have got away with those shells, they`re showing signs of light wear but i expect they`d measure up OK.
Looking forward to the rebuild a potential hurdle will be sourcing head gaskets that work.
OEM no longer available, all pattern ones are junk.....

 

[CXPHREAK]

Doesn't Murray have Joe Hovel 650 head gaskets?

 

[jlbutler81]

Doesn't Murray have Joe Hovel 650 head gaskets?

He does and they'll be ordered. And rings because why not

 

[CXPHREAK]

Likely the compression rings are fine - but the oil rings are likely slack. 650 trick.

I've used the Hovel gaskets and they're good. They do need a number of retorques though.