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Cylinder Head Cover Leak

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Martin6:
Hi All,

I've got some problems!
Photo 1 shows damage to the head to cover's gasket face, from a gorilla previously taking off the head cover (bottom left of photo). The second photo shows the same area on the cover. This was one of my leaks. Is there a sound way to repair this damage and get a seal?

The first photo also shows one of the cover screws still in the head. The screw head sheared. Penetrating oil isn't helping. I have the same problem further round, but this time the screw sheared at its bottom, right at the head face. The ez-out hasn't worked. Any suggestions on these?

The final photo shows how mucky the camshaft, chain, sprocket and valve gear are. Carbon and dirty oil, despite 3 oil changes in 1500 miles. Is this unusually dirty?

Helpful suggestions and advice would be appreciated. Feeling concerned about the state of my motor and whether I'm up to fixing it!

Thanks, Martin

Nurse Julie:
Blimey, looks like a big rat has been nibbling that. You'll be lucky to salvage it. Black staining is not unusual, it's a sign of very high heat and dirty oil through not doing regular oil changes.
Edit... I should have said you will be surprised how much of that black comes off when cleaned thoroughly but, I doubt it will all come off.

McCabe-Thiele (Ted):
In my experience dirty oil can be due to high detergent content such as with oils designed for  diesel engines or bore wear.

Different situation but I know a guy I worked with who bought a Civic Honda Type R that had not been serviced regularly. He put it on the ramp at work he did four successive oil changes running the engine for 15 minutes between changes until it came out pretty clean. He did a final change with a second oil filter. As it was VTEC he did not want to risk flushing oil.

Might be worth using a Silicone based sealer with  new seal to cure the oil leak.

Martin6:

--- Quote from: Nurse Julie on October 10, 2023, 04:44:06 PM ---Blimey, looks like a big rat has been nibbling that. You'll be lucky to salvage it. Black staining is not unusual, it's a sign of very high heat and dirty oil through not doing regular oil changes.
Edit... I should have said you will be surprised how much of that black comes off when cleaned thoroughly but, I doubt it will all come off.

--- End quote ---

I think a previous owner used a hammer and chisel! The damage goes right across the gasket face of the cover. The damage to the head is on the outside edge, right up to and including the outside edge of the screw hole. I don't know if it would seal, if the cover was sound.

I've found a used cover with good gasket surfaces. I'll try to clean up the outside.

What's the best thing to do about a head? I think it will have to be replaced. I will have to buy 'used'. Are K6's the same as earlier models? I'm thinking it would have to include the valves. Happy to re-lap valves, but not try to cut in for new ones.

Other than ebay, any suggestions on where I might get a decent one?

Pauarc:
Hi Martin
I had a similar issue with a cb550 I managed to get the gasket face skimmed and put two gaskets there maybe it will be possible for you
Paul

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