550 head gasket - slight oil leak

[andy_c101]

Hi,
This Autumn my 550K3 developed a slight oil weep at the LH-end (No1 Cyl) of the head gasket.
Nothing too serious, just an obvious wetness after say a 30mile run.
["I'm a great believer of "if it ain't broke don't fix it", but then I dont suppose this will cure itself!]

Isn't there an o-ring seal for an oil way from block-to-head on that side?
Its probably the original seal, so after 35years its must be due for replacement.

Me thinks its time for a top-end overhaul.
I think the "head-off job" is "a tank-off, in-frame job" isnt it?

Andy C

[Bryanj]

Its a small "O" ring leaking but leave it alone till its leaking liquid. You need a COMPLETE top end set

You can strip down to base gasket level with engine in the frame and if you pull the head without lifting the barrels and changing the base gasket along with the "O" rings you are asking for future trouble

[andy_c101]

Bryan,
thanks or the tip.
Andy

[z1100r]

 I'll agree in this case as it will be the - imposible to argue against - thing to do.
   However, I myself wouldn't do it, I raced a 460 and 500/550/600 for a number of years during which time the tuning  was a work in progress and consequently the heads were constantly on and off - say 5 or 6 times a season and through the winter aswell.  I never once took the barrel off. I've swapped just the head loads of times with no problems at all. 

  You take each engine as you find it though I guess, an unknown engine i would strip anyway, but one I'd had for ages and knew didn't smoke and ran beautifully I would'nt strip, i'd just fix the oil leak.

[SteveD CB500K0]

For a road bike, I'm with Bryan.

The force needed to separate the head from the barrels will most probably break the barrel/case join as well, leading to more work later.

On a race engine with multiple tear-downs per year, I can imagine that this would not be the case.




So you're both right!

 

[z1100r]

 Yeah Ok Steve, I was just pointing out that its not the totally wrong thing to do.
    I've advised folk to do the job 'properly' in the past only to find they go and break the piston rings refitting the barrel - one bloke even forced the piston up the barrel with a ring half in half out, making a right nasty groove, or they fit the cam chain guides incorrectly, or they snap studs, or fill the crankcase with sand and grit from those open barrel studs.

 Narrgh if I just had an oil leak on an otherwise OK engine I would just fix the leak and not ask for all those other potential problems.

 I've never had to use alot of force on any of my heads, even ones that hadn't been removed before from new..?? Find slot and appropiate lever, they just 'squeeze' up in my experience.

[Bryanj]

When i used to work in the trade there were many jobs where we explained to the customer the right way and the "cheap" way and they would invariably take the cheap way then come back and complain about a problem we had warned about so I just stopped saying there was a "Cheap" way.

Plus by the time you have bought the necessary "O" rings and seperate head gasket from Honda you can have a full set from Dave Silver, I agree about the people not assembling correctly but if they don't read the manual about fitting the chain guide, chances are they won't read about the rocker arms and bend a valve then i get a cheap parts bike!! (Or is that a little too cynical at Christmas)

[Tomb]

then i get a cheap parts bike!! (Or is that a little too cynical at Christmas)

 

Yep I like folk like that, I was once given a GSX250 in big boxes by a bloke down our road, he'd stripped the engine to do a job, failed and passed it on to me for parts, that was Saturday afternoon, by Sunday night I was riding it up and down the road and MOT'd it on Monday, sold for

[SteveD CB500K0]

Off topic (a bit), but...

I bought a non-runner CG125 for my son when he was 17.
"It's seized"
What was seized was the centre stand spindle which doubles as the rear brake spindle. Rocking the bike off the stand rammed the rear brake on...

I "unseized" it and Chris rode it around for a year or so until his CBT expired.

The he bought a car 

I sold it for

[matthewmosse]

I'd leave it be  or go whole hog on top end removal (getting old head gaskets off can ba a trying expirience as they can stick like **** to a blanket. On my 5004 outfit I did 100,000 miles on an engine with such a leak with no ill effects. Top end was exceptionally good when I finally stripped it down at 180,000 miles on the clock due to it jumping out of 1st gear