Oil leak head gasket.

[Fredrik]

Hello.

This is on my V7 Special -1971. Oil coming from the head gasket, how common and how serious is this? Same on both sides.

[Pescatore]

Hey Fredrik, if the problem is the same as this https://wildguzzi.com/forum/index.php?topic=117942.msg1861350#msg1861350,
then it's a matter of time for these old machines.

[czakky82]

@ Fredrik, I’ve successfully pulled the heads and replaced the head gasket before without disturbing the base gasket FWIW.

[Fredrik]

I dont have time to change the gaskets at the moment based on i will use the bike from thursday this week for vacation touring. And the gaskets must be ordered etc. Guess i can live with a few oil drops the coming two weeks and then change all the gaskets from bottom and up on the cylinders/heads. 

[czakky82]

Re-torque?
I’m sure you have already.

[Fredrik]

Re-torque?
I’m sure you have already.

Yes i did retorque last year and did it today as well. No direct difference.

[guzzisteve]

Round cyl bigblock. Not a compression leak but just a bit of oil may be the orings on studs under the rocker bridge.
You can change the orings with the 2 short studs tight, then loosen to 1st torque setting after bridge is back on. SO, no head warpage and not loosened where it would leak.

[Antietam Classic Cycle]

If it's just a few drops now and then, I wouldn't worry about it, just ride it.  I doubt the rest of the bike is leak free.

[Fredrik]

If it's just a few drops now and then, I wouldn't worry about it, just ride it.  I doubt the rest of the bike is leak free.

Acually, it is. This is, at the moment, the only leaks. 

[pehayes]

Before presuming it is the head gasket or o-rings, how about the seal for the access plug to the top-center head bolt?  The older bikes used a flat crush washer.  Newer bikes used a large o-ring (prone to hardening from  heat cycles).  Often that leak will drain around the cylinder and drip off under the spark plug area.  Add a thin sealant layer to both sides of the flat crush washer or change the o-ring, whichever  you have.

Just a quick easy fix but it likely is your aged stud o-rings.

Patrick Hayes
Fremont CA

[Scout63]

I would just ride it, and park it next to a Brit bike if possible.

[jacksonracingcomau]

Acually, it is. This is, at the moment, the only leaks. 

Yeah, fix it
That would piss me off immensely, the only leak that gets on your boots/levers, makes changing gears and braking slippery and ruins your Gucci’s

Can’t see O rings making oil come out there, looks like simple gasket change to me but odd that you’ve just put it together and both leak, post some pix when apart after you’re back
Enjoy trip, don’t wear your Gucci’s this time

[Pescatore]

Quote from: jacksonracingcomau on Today at 11:36:07 AM

Yeah, fix it
That would piss me off immensely, the only leak that gets on your boots/levers, makes changing gears and braking slippery and ruins your Gucci’s.

+1
It's amazing how oil mist gets all over the bike, to the rear wheel.
Stuff a paper towel or something to absorb the oil while riding.  Worked for me until I had time to repair it.

[jacksonracingcomau]

Quote from: jacksonracingcomau on Today at 11:36:07 AM

Yeah, fix it
That would piss me off immensely, the only leak that gets on your boots/levers, makes changing gears and braking slippery and ruins your Gucci’s.

+1
It's amazing how oil mist gets all over the bike, to the rear wheel.
Stuff a paper towel or something to absorb the oil while riding.  Worked for me until I had time to repair it.

Cut a piece of towel and shove between fins like a tampon, far more absorbent than paper
But still, wearing Guccis is a gamble

[pehayes]

Can’t see O rings making oil come out there, looks like simple gasket change to me but odd that you’ve just put it together and both leak, post some pix when apart after you’re back

'jacksonracingcomau'  I went back through the thread.  I can't see where this engine was apart and rebuilt recently.  What suggested that to  you?  Perhaps another thread?

Here's a wild guess.  Just tossing out ideas.  The cylinder base gasket includes two o-rings for the upper/center and lower/center mounting studs.  The cast cylinder body includes a countersink or chamfer recess on those two stud holes to accept and compress the o-rings.  If one didn't understand that, it would be quite easy to install the the o-rings below the gasket and mess up the compression/sealing relationship.  Might that allow oil to gradually rise along the stud and ooze out at the head?  Or perhaps those below the cylinder o-rings were left out completely?  I'd like to hear more about prior work.  Is the assembler certain they got all those parts installed correctly?

Patrick Hayes
Fremont CA