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Discussion Starter #1 (Edited)
I dont think I can provide anything new so I wanted to make 1 thread to ask all my questions. Appreciations to all who follow.

First question, I pulled my head off and it was black like this on the top. The gasket all came off really easy and in 1 piece. WHy is there so much soot/grease/dirt up there, was the head gasket bad or does this thing just have a grease magnet there? Its like this all the way around.

I had gotten this bike running and planned to ride it 1 season before rebuild. Glad I didnt, check out the pic of my rollers. I had to double check my part numbers! Are these bad or what?

Ill have more questions to determine what actions are recommended for me.

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Yep, those cam chain rollers are pretty well worn, likely in part from lack of adjustment maintenance. Unless the cylinders were once painted black, it's a strange look that I've never seen anything quite like before. Maybe the PO greased the head gasket before he installed it so it would break free more easily later, but the oozing grease burned on the top fins of the cylinders? Definitely strange
 

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I guess it's possible but again, back when I was doing this stuff on a daily basis, I can't recall ever seeing one coated like that without a lot of oil running off the fins - and then it was cleaner than yours because oil flow out of a warm engine washes away stuff (unless it really overheats badly at which point some gets baked on), and yours is like that all around, not just in one area
 

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Is it oil or carbon?

Is it combustion carbon (head gasket) or soot (burnt oil from leaking rocker box)?

What's it look like under the gasket?

Whatever it is, one must keep in mind the engine is 45+ years old and from the looks of the rollers, probably never apart. Probably not the worst gunk you're gonna find in there and at least it's on the outside!
 

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My 450 was weeping oil out the head gasket. Then with traffic completely at a stall, along with hot weather, it just coked the oil and almost did in my custom voltage regulator. I reverse engineered it and put in a different zener diode to cut the voltage down a bit. The engine got so hot it vaporized the lead out of the tin/lead solder causing some open circuits. Resulting higher voltage burned out head lamps prematurely. I've learned since to just pull off the road, turn off the engine, let it cool down, call my wife to say I'll be home late for supper, and rejoin traffic after it speeds up.
 

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Discussion Starter #7
Here are some more pics. The grease (oil?) can be wiped off with a rag if I push my fingernail into it as shown. Also shown is underneath the head gasket. I also provided a pic of the cylinder head botton. Some grease there but mostly clean with the brown baked on stuff which I guess is oil?
Is this evidence this motor might be a goner? It had 160 psi compression cold and it run perfect last spring though I never rode it then as I decided not to buy tires yet and rebuild this winter.

I wonder if the head maybe leaked at one time then self sealed? NO evidence of copper like someone tried a liquid fix.. Odd.

GOPR0255.jpg GOPR0254.jpg GOPR0253.jpg
 

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I'm leaning toward paint. Thinking someone did have this apart. That would explain why the gasket came off so easy. The jugs were likely painted with regular rattle can black instead of a hi-temp paint and the top of the cylinder (where the fire happens!) being the hottest part...

The bottom of the head definitely shows oil leaking and undoubtedly running down onto the cylinders (this is not unusual). Could still be what this gummy goo is! If you scrape a chunk off, like a small "sheet" and it has ANY elasticity at all. I'd say paint. If it has NO elasticity - breaks/crumbles -then probably (dust &) oil.

Maybe the PO just put the old rollers back in. Maybe they were never adjusted correctly. Maybe I'm full of... :-?

Your engine IS NOT toast! If you had 160psi you're better off than some that are riding!!! This is just a bump in the road and an opportunity for a learning experience! ;)

BTW, there should not be any oil to leak here. The oil would come from the cam case down onto the cylinders. If you had enough oil in the compression chamber to cause ANYTHING from a leaking head gasket you'd have noticed the smoke that prevented seeing your tail light when it was running. :D

Again, this is no big deal in and of itself! Oil leaking from the cam case is much better than not having enough up there.

EDIT - Just looked at your photos again. Looks like a lot of that goop at the rear. What did the tensioner gasket look like when you took THAT off?
 

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Yes, with 160 lbs of compression it most certainly was not the head gasket leaking cylinder pressure, so carbon is not the culprit. The 350 head gaskets can leak oil as well, as all the older twins routed oil flow to the top end by way of the cylinder studs and often leaked a little from the head gasket around the area
 

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Normal oil and crud on those cylinder fins in my experience.

The one area to check is on the bottom of the cylinders and top of the cases where the large pin the tension arm pivots on is located. If it is hammered out you have problems.

Also check that pin, the one with the notches on either end for grooves caused by the tension arm. I just replace that piece and the bushing the wheel rolls as part of a rebuild.
 

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Discussion Starter #12
The tensionor I took off last winter, the gasket was normal hard and waxy.
The crud came off like built up grease and dissolved off sitting in kerosene

As I inspect more I am going to see what you guys thing if it has been apart before. there are some marks on the gasket mating surfaces but not sure what is normal out of factory.

I will tell you after getting into this bike, its very Heinz 57. Someone at one time must if resurrected it. I've had it 25 years so this was long time ago.

Ill have more questions, thanks for your help!
 

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Discussion Starter #13
Ok guys need some advice here. Attached is where I am at. I took the pistons off and Im kinda curious if I should have done that. HOw much further should I go? I can split the bottom case off to inspect the gears and clean up/out everything. I gotta find all the rubber bits from the tensionor.

Assuming gears are good, connector rods in tolerance, is there any point in removing the counter and drive shafts from the case?
My goal is to get this bike to last another 20 years so when Im 60 I can do it all again!

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I thought you said you rode this bike and it had 160 psi compression? Please remind us why you are tearing it down? :-?

There's nothing wrong with doing that if that's what you wanna do. It is yours afterall, I'm just curious if there was some problem you're trying to find/solve or if this is merely an "inspection."
 

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Discussion Starter #15
I thought you said you rode this bike and it had 160 psi compression? Please remind us why you are tearing it down? :-?

There's nothing wrong with doing that if that's what you wanna do. It is yours afterall, I'm just curious if there was some problem you're trying to find/solve or if this is merely an "inspection."
Did you see the picture of the chain tensionor? This is why I tore it down, and its worse then I thought. Originally I had a lot of rubber in the oil. Would you agree I did the right thing?

So my question stands, any reason to split the bottom? I am wondering if I have to in order to replace cam chain?

GOPR0251.JPG
 

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To do the cam chain the right way - IMO - yes, you should tear down the bottom end as well. You will find a lot of gunk in it along with the rubber bits from the rollers, and it will give you the opportunity to inspect the transmission gears and shift forks while you're there. The bottom ends are actually easier than the top end, simple and straightforward, only a couple little things to watch out for... and you'll get plenty of help on all of it.
 

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Originally I had a lot of rubber in the oil.

THAT is what I was looking for and obviously missed. Some issue that begun the teardown.

Yes. I would agree that you did the right thing! However, if you'd just done it for curiosity, I have no issue with that either.:D
The purpose of my question was simply my own curiosity.
 

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Discussion Starter #18 (Edited)
Quick question, is it worth it to invest in all the measurement tools needed?
Or should I just send everything to machinist to check and fix up and put the $ towards that? The tools I need will be around $150-$200:

Micrometers
bore guage
hole guages
telescoping guages
spring removal tool
 

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Most all Machine Shops will do the measuring for you for built in as part of the overall job.
Unless you are proficient at using the measuring tools "AND" have plans to use them multiple times in the future to justify the cost just let them do it.
 

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If the mechanical work is something you would love doing and have the time, try to take it on yourself. I've even reused piston rings if the ring gap wasn't excessive nor their play in the piston grooves. Everyone has feeler gauges. Some of the new ring kits come with 3-piece oil rings which aren't my preference. You'll need some form of ring compressor tool. If you can get away from disassembling the transmission case and can clean the crud directly below the crank shaft with kerosene, that is in your favor. I know 450's, not 350's nor 360's. Jim Palmer found a good way to seal the cylinder to the transmission case on his 450. I've sometimes greased head gaskets, sometimes put them on dry, sometimes sprayed aluminum paint on them, sometimes used Gaskacinch (sp?). Don't reuse O-rings or the special rubber rings at the head gasket but ensure the new ones are thicker than the head gasket to seal the lubrication up to the cam shaft(s), being squeezed when torquing the head/cylinder arrangement.
 
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