Head Gasket

[SpanishJohn]

Yes, These are the drain holes for the spark plugs. There must be oil ingress into the spark plug area which is/was sealed by the valve cover gasket. You will need to remove the valve cover (not trivial) and renew the culprit (or just the whole gasket if it comes as one). The spark plug recess will also need cleaning. TBH it sounds to me that this job should be done by a competent mechanic rather than yourself. However, to verify, simply remove the tank and unplug the suspect spark plug socket. It should be covered in oil.

Spanish

 

[Jaws]

Yup.. Cannot believe I have never investigated those holes but 100% that is what it is.. rocker box gasket unseated
Chances are VERY high you will not even need a new one.
You need to go to a small car spares shop and get some of that nasty black gasket goo.. That will hold the gasket in place properly while you refit the rocker box

 

[silverfox.xx]

How difficult is that to see the coolant level. Why don't they make them from clear plastic??

Shine a touch (LED not as good a halogen/filament bulb) in the top of the tank with the fill cover off, then look at the tank from the rear RH side, sort of looking up.. below the tail piece cover.

As for the leak... tank off and have a look from above/around the plug holes.

 

[Tinytim]

Still hard to see.

 

[andyBeaker]

Shine a touch (LED not as good a halogen/filament bulb) in the top of the tank with the fill cover off, then look at the tank from the rear RH side, sort of looking up.. below the tail piece cover.

As for the leak... tank off and have a look from above/around the plug holes.

Think laterally = stick a bit of tube into the top of the tank and start blowing while lowering the tube. when you get bubbles you have hit water!!

 

[Gammo]

What would have caused the rocker box gasket to move? I did put her down twice last year but i think i took most of the impact as i was still on her. How difficult a job is changing the rocker gasket. I'm not totally incompetent when it comes to spannering.

I would just like to say that without you guys I would have spent a fortune at a dealers and believed anything they told me as I wouldn't know any better. I cannot thank you all enough for the invaluable advice that you give time and time again.:bow:

 

[Demonbane]

the next thing to check gammo is that the spark plugs are tight ,it may be the one where you are seeing a little oil has come loose a fraction (had that once,where the sealing copper ring had a little dirt under it and leaked a little.)

someone will correct me if im wrong, but from cold,oil does seep past the rings in very small quantities,so a quick check of the plugs is the place to start.

 

[Jaws]

I have seen it but hell, that would have to be some seriously shagged out oil control rings to let that much by !!
So after it proly being a ?40 max job we are back to staring down the barrel at about ?700 !!

I reckon the gasket was never seated properly when the valve clearences were last done ( or maybe even from new ! ) and standing it up in the cold has deformed the rubber/neoprene gasket to deform JUST enough to let it leak .

It is a bit of a bugger of a job but not THAT bad.

I always pull the loom away from the left hand side of the frame where it is attached by a plastic clip to give me a bit more room to get the rocker box out the top
No need to disturb the rad or anything at all

use that black gasket locater stuff I mentioned to hold the gasket in place while you put the rocker box back down ... Fiddly and you have to be VERY careful, but well within the range of the average home mechanic

 

[Smiler 1957]

Different thing i know but i have had fork seals on bikes that have not been ridden for a while show oil on the fork , but then revert to doing their job once put in use . Looks like just the cam cover gasket

 

[silverfox.xx]

Different thing i know but i have had fork seals on bikes that have not been ridden for a while show oil on the fork , but then revert to doing their job once put in use . Looks like just the cam cover gasket

Rubbers dried out and gone a bit hard, needs new seals to cure it IMHO, now was the bike left on the side stand, as Bunny had a similar thing, and has not had a problem now its parked on the centre stand.

 

[Gammo]

If it was an oil control ring problem how would the oil get past the spark plug to come out of the drain hole? Surely I would see some blue smoke or smell the oil burning if was getting into the combustion chamber?

 

[Tinytim]

For Fooks Sakes

If it was an oil control ring problem how would the oil get past the spark plug to come out of the drain hole? Surely I would see some blue smoke or smell the oil burning if was getting into the combustion chamber?

:bang:

Gammo...You've had this problem at least a fortnight and been given many suggestions ( several then O.K.)...about answers. Some, suggesting you work on the engine out of the frame, defy belief after you state you are totally incompetent at spannering :bow: ..... and ya still come back asking questions.. Get on with it, take it to a mechanic and get the fooka sorted otherwise the Summer will have been and gone.


Oh, and then tell us what it was....Good luck. :yo:

 

[Jaws]

Now sorted ( by the man himself ! )

 

[Gammo]

Yep. Thanks for the gasket John.
It was a leaking valve cover gasket around no. 4 spark plug recess. Haven't quite finished putting it back together just got to put the air box back on and then the tank. It was a bit of a pig getting the cover in and out but we got there in the end.

Just out of interest why does the cylinder head have those large cut outs at each end that are filled by the valve cover gasket?

 

[Jaws]

To help with extricating the cam shafts .. The head is shared with other models

 

[andyBeaker]

Great, another happy ending.

and another case where the problem was nothing like as bad as first thought.

Been there, done that!!

 

[rhubarbray]

Yep. Thanks for the gasket John.
It was a leaking valve cover gasket around no. 4 spark plug recess. Haven't quite finished putting it back together just got to put the air box back on and then the tank. It was a bit of a pig getting the cover in and out but we got there in the end.

Just out of interest why does the cylinder head have those large cut outs at each end that are filled by the valve cover gasket?

At the factory the heads have the cam caps installed, torqued, and then the assembly is line-bored. The tool must enter from the side which is why there are cutouts in the side of the head but not the valve cover. This is also why cam caps GENERALLY cannot fit on another engine. The mating surfaces may be offset just a hair and it`s enough to bind the camshaft.

 

[CyberXX]

Yep had the same problem on a 1984 CB900 F2, rocker cover gasket leaked like mad.

Not a massive job to replace, but ended up rebuilding the engine anyway with help from a local formula 3 mechanic