Metal gaskets

[belfastguzzi]

Yes, it's a bit of a double-post as I mentioned this in the CARC forum.

 

I'm looking for advice as once again I haven't had a response from either the only Moto Guzzi dealer left in the Province, nor Moto Guzzi UK's agent – even though this must be a warranty issue.

 

What is normal practice with metal gaskets? Can a gasket be re-used or should it be replaced once the joint is loosened?

 

As far as I can see, the Griso's 1200 8V is leaking from the barrel base joint.

The heads were off to replace cams at (eventual) recall. Do the bolts run right through the barrels to the main engine block and so when the head is removed the barrel is loosened at the base joint too?

It has been said that re-torquing won't help as the metal gasket is incompressible, but even if it won't compress any more, could further tightening simply seal the joint again?

 

Apart from the oily mess, how problematic is a leaking base gasket?

[stockport claret]

Hi Dave,

Would have thought that metal gaskets were once only use, as they are usually of the crush type and so form to the metal they are crushed between and form a seal.

For what they cost, it would make sense to change it if ones been loosened. But it sounds like this may not have been done.

Further tightening the bolts could cause damage to the cylinder head or stretch the bolts themselves.

 

I've just had to have the timing cover gasket on my Mandello replaced as it was leaking. I'd tried tightening the bolts around the leak area but to no avail.

The timing cover gasket is a thin metal type with a central ridge which forms a seal when it's compressed.

The problem was that at speed the oil was running along the length of the sump and ending up on the rear tyre which made for some interesting handling.

[gstallons]

I would reuse a metal shim style gasket using Loc-tite 515 anaeorbic (sp) sealer or Yamabond. Any type of sealer should be used sparingly with it just oozing out of the mating surfaces when tightened.

[Greg Field]

They're single-use gaskets. It they loosened the head bolts, they should replace the base gaskets, if they're the metal crush type.

[belfastguzzi]

They're single-use gaskets. It they loosened the head bolts, they should replace the base gaskets, if they're the metal crush type.

sorry to ask another question that I should probably know the answer to without asking, by thinking about it, or by looking at a parts diagram...

 

when doing the cam replacement recall work, would the head bolts be loosened? Do the nuts that hold the cam 'cages' also hold the head on and so tighten down the head and barrel?

 

Thanks.

[pete roper]

Nowhere in the cam instructions does it state that the head or base gaskets need to be replaced.

 

I too was wary of this as i knew there would be a *risk* of leakage after tension was taken off the head studs. For that reason I was VERY careful not to knock or jar the cylinder or head when removing or replacing the cam-boxes and obviously it was VITAL that the crank not be moved while the head and barrel weren't under tension.

 

Mine haven't leaked. I have heard though of other ones that have but of course I have no idea of the proceedure that was followed, or not, during the cam replacement.

 

Pete

[stockport claret]

Do the nuts that hold the cam 'cages' also hold the head on and so tighten down the head and barrel?

 

The workshop manual pictures show the that the nuts holding the cam cages are the nuts for the cylinder head bolts. So it looks as though the cylinder heads may have been knocked and the the cylinder head/crankcase gasket seal broken.

Hope you get some joy from the dealer and Guzzi about this.

Trevor

[pete roper]

The workshop manual pictures show the that the nuts holding the cam cages are the nuts for the cylinder head bolts. So it looks as though the cylinder heads may have been knocked and the the cylinder head/crankcase gasket seal broken.

Hope you get some joy from the dealer and Guzzi about this.

Trevor

 

The rocker support/cambox assemblies are retained by the same studs and nuts that go right through the head and barrel and into the block. The bolts that hold the cambox 'Halves' together are something else entirely and will have no effect on gasket sealing.

 

Why this has happened is really a moot point. The fact is that it needs to be fixed and that will require removal of the head and barrel. Make sure the bloke who does it understands that the gaskets come in a variety of thicknesses for accurately setting the squish so he should MEASURE the old ones before ordering. I'd also be very wary of applying much goop to them as the oil feeds both for cooling and lubrication pass up one of the studs that penetrates the gaskets you don't want that gallery getting blocked with muck. Also ensure that the tab plates on the inner rear (?) studd are installed correctly as I believe these have a centering function for the stud in the gallery.

 

Pete

[belfastguzzi]

Why this has happened is really a moot point. The fact is that it needs to be fixed and that will require removal of the head and barrel. Make sure the bloke who does it understands that the gaskets come in a variety of thicknesses for accurately setting the squish so he should MEASURE the old ones before ordering. I'd also be very wary of applying much goop to them as the oil feeds both for cooling and lubrication pass up one of the studs that penetrates the gaskets you don't want that gallery getting blocked with muck. Also ensure that the tab plates on the inner rear (?) studd are installed correctly as I believe these have a centering function for the stud in the gallery.

Unfortunately Pete, all of this seems to be a moot point, as there isn't anybody in the country who understands any of it.

The only solution would seem to be for Guzzi to abandon its dealer-warranty system and instead just let anybody do the work.

The end result couldn't be any worse than the present situation and there is every chance that it would be much better. But that's not going to happen.

So I'm at a loss...

[pete roper]

Unfortunately Pete, all of this seems to be a moot point, as there isn't anybody in the country who understands any of it.

The only solution would seem to be for Guzzi to abandon its dealer-warranty system and instead just let anybody do the work.

The end result couldn't be any worse than the present situation and there is every chance that it would be much better. But that's not going to happen.

So I'm at a loss...

 

ARRRGH! But it's not anything special?? Just standard automotive practice?? There has to be SOMONE in Ireland who can replace a head and base gasket for f@cks sakes???

 

Pete

[belfastguzzi]

ARRRGH! But it's not anything special?? Just standard automotive practice?? There has to be SOMONE in Ireland who can replace a head and base gasket for f@cks sakes???

 

Pete

Yes. That's what I mean – Guzzi should allow some other competent mechanic, or me as owner, to do the work. I'm just talking about the Moto Guzzi 'system' as this has to be a warranty matter.

So far no response at all (as before) from the only dealer/agent left here, nor from the UK importer.

Plus, if the damage was done during the recall work (which is how it looks) then it doesn't inspire confidence in even more work (lifting top half off) to put original work right.