Topic: Top end work: Just how much can you do in the frame?

[Scott S]

 My CB500 has some minor oil leaks on the top end. Most of them I can get to easily (tappet covers, breather, etc.). However, it looks like maybe there's a leak where the head meets the cylinders. Can I change that gasket with the engine in the frame?

 None of these leaks are major. I'm just anal about that kind of stuff and it drives me nuts. Nothing so severe that the bike can't be ridden (or even kept clean with the occasional wipe-down).

 What about re-torquing the engine bolts? I did pull this thing out of a barn this Spring, where it had sat for more than 28 years.

 The P.O. even told me that he had rings and a valve job done on the bike way back when, before he parked it.

[Gordon]

All top end work on the 500 can be done with the engine in the frame.  Only the 750K & F have to be pulled, unless the frame has been modified. 

[MCRider]

My CB500 has some minor oil leaks on the top end. Most of them I can get to easily (tappet covers, breather, etc.). However, it looks like maybe there's a leak where the head meets the cylinders. Can I change that gasket with the engine in the frame?

 None of these leaks are major. I'm just anal about that kind of stuff and it drives me nuts. Nothing so severe that the bike can't be ridden (or even kept clean with the occasional wipe-down).

 What about re-torquing the engine bolts? I did pull this thing out of a barn this Spring, where it had sat for more than 28 years.

 The P.O. even told me that he had rings and a valve job done on the bike way back when, before he parked it.

I'll have to pass on 500 specific questions, but the rings are likely rusted up from sitting. And the valve job has aged in that, certain valves were open during the parked period, and those valve mating surfaces (seats) will have rusted as well. So not much value there.

Age is as much the bad news here as high mileage might be on something else.  It could still run fairly well though so I hope you get good answers to your other questions.  Run some SeaFoam thru the gas and oil.

[Scott S]

 The bike runs like a dream. I gave it a good tune up. Changed the oil twice in the first hour or so of run time. Changed the oil and filter after a few hundred miles. Pulled the sump last week to replace a stripped/re-tapped drain plug and everything looked fine.

 I ran some Seafoam through the gas, but haven't ran any through the oil. It doesn't smoke or use oil, just has some annoying (to me), yet very, very minor leaks.

 That's good news that I could freshen up the gaskets and stuff without removing the engine. 

[MCRider]

The bike runs like a dream. I gave it a good tune up. Changed the oil twice in the first hour or so of run time. Changed the oil and filter after a few hundred miles. Pulled the sump last week to replace a stripped/re-tapped drain plug and everything looked fine.

 I ran some Seafoam through the gas, but haven't ran any through the oil. It doesn't smoke or use oil, just has some annoying (to me), yet very, very minor leaks.

 That's good news that I could freshen up the gaskets and stuff without removing the engine. 

Good that it runs good, could have gone either way.

The SeaFoam can dosen't address this, but many think it best to put the SF in the oil shortly before a change, letting it do its work and then get it out.

I've just poured it in whenever I wanted, no repercussions.

[Gordon]

The SeaFoam can dosen't address this, but many think it best to put the SF in the oil shortly before a change, letting it do its work and then get it out.

I've just poured it in whenever I wanted, no repercussions.

That you know of.

It may not do much noticeable damage depending on how much you put in, but putting anything in the oil that thins it out and letting it run for any length of time can't be good for the moving parts that need lubrication. 

[JBMorse]

As said above, the CB500/4 top end work can be done with the engine entirely in.  However, it's so damn easy to remove the CB500 engine, that I've opted to do that on mine.  At first I pulled the thing apart with the engine in but decided to pull the engine out for re-assembly.

[MCRider]

The SeaFoam can dosen't address this, but many think it best to put the SF in the oil shortly before a change, letting it do its work and then get it out.

I've just poured it in whenever I wanted, no repercussions.

That you know of.

It may not do much noticeable damage depending on how much you put in, but putting anything in the oil that thins it out and letting it run for any length of time can't be good for the moving parts that need lubrication. 

I've got to admit its an interesting issue. I just re-read the can to be sure. They only say, for crankcases add 1.5 oz per qt. No legend "50 miles before oil change" or anyhting like that. I just can't imagine a company would open themselves to lawsuit for an oil additive that did harm. I think whatever may thin the oil, if in fact that happens, evaporates off in short order and it probably leaves behind something similar to the low friction additives in modern oils. For that reason one may want to get it out to spare the clutch. ,

Still I may do the "before oil change" approach just becuz it sounds better.  Or not.  

[TwoTired]

All the top end/cylinder work can be done with engine in frame for the 500/550.

To get to the oil passage orings that weep and bug you, you have to remove the head.  Doing so usually disturbs the cylinder base gasket which will begin to leak afterward.
So, all gaskets and seals need to be replaced from the engine block on up to satisfy your lust for leak free.

You run the risk of breaking, damaging piston rings during cylinder block reassembly, snapping off or pulling out cylinder studs, stripping out threads in various aluminum castings, bending valves while improperly installing the cylinder cover, and getting the cam timing wrong and bending valves that way, too.

If everything goes right, and you have pretty good mechanical prowess, it only costs a gasket set.


I see no need to add seafoam to the crankcase, unless you can't help yourself from meddling with unknowns.

Cheers,

[Gordon]

Seafoam isn't a lubricant, it's a solvent.  So yes, it will thin the oil.  Like I said, though, putting a small amount in the oil probably doesn't do much noticeable damage, but it still can't be good for the lubricating ability of the oil even if it's negative effect is only very minor.  

[MCRider]

Seafoam isn't a lubricant, it's a solvent.  So yes, it will thin the oil.  Like I said, though, putting a small amount in the oil probably doesn't do much noticeable damage, but it still can't be good for the lubricating ability of the oil even if it's negative effect is only very minor.  

SeaFoam disagrees with you, claims to have lubricant in product. To avoid further thread jacking I'll direct interested parties to their website, FAQs, etc.
http://www.seafoamsales.com/motor-treatment.html