dead cylinder

jg213 wrote:

Have found a dropped intake valve.  Hoping maybe piston is ok?

I really feel for you - good luck

GuzziSteve wrote:

Solid pin between cam sprocket & cam. Right inside the cap/vent for cam chain sprocket. You'll see it, unless it came out a hole lined up from roller conversion(some wenches did that) that would explain a drop valve.

verified pin aligns with mounting holes.  now looking for tensioner.  seems to be on top underneath gas tank.  going to pull tank and have a look.

looking for how to pull quick disconnect...  like just pull it?

found a utube about disconnect, just had yank a little harder. so, head came off just fine. the valve is bent and stuck in a position where it seems to have just barely contacted the piston. I have a picture, presently going to try and get it on here.

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doesn't seem too beat up
upper left is the area in question

I would look on inner side, may be cracked. Hard to tell from pic on condition.

Sounds like either the spring broke or something else occurred and it spat out the collets on that valve allowing it to drop. I'd say you have been extraordinarily lucky!

Now you need to take the head apart and find out if the guide is toast.

Pete Roper wrote:

Sounds like either the spring broke or something else occurred and it spat out the collets on that valve allowing it to drop. I'd say you have been extraordinarily lucky!

Now you need to take the head apart and find out if the guide is toast.

there's a little clip on top of the valve stem that came off. betting it's down in bottom of oil pan. also, something got inside combustion chamber and pinged up the piston top a little. I'm thinking it's not too bad. Also, do I need special tools to work on valves? Maybe should send off to specialist?

The little 'Clips' are called collets or in some places 'Keepers'. They have a ridge at the wide end that sit in a groove in the valve stem. There is a matching taper in the cap on the end of the spring that the cone shaped collets fit into and the spring pressure should prevent them jumping out, even at 80 times a second of the valve going up and down.

Now if it's spat a collet out there will be a reason. A weak or broken spring? A buggered valve guide allowing the valve to squirm about rather than simply going up and down? At the moment nobody knows.

As it is you need to take the head to a specialist engine rebuilder. They will have all the tools to do the job of replacing what needs replacing and machining the seat to match the valve. You will probably have to find somewhere 'Old School' as Guzzi don't sell valve guides as a separate part which means that if the guide is stuffed they will have to manufacture one and install it. Guzzi will sell you a complete head, for a couple of grand! How about 'No!'

I would find a decent engine rebuilder, (NOT a motorbike shop!) and ask them what you need and then purchase the parts required for them. You will need to pull the barrel as well because you'll need to examine the piston. You may find that as the valve has clouted the piston it has squeezed closed the ring lands, (The bits of the piston above and between the rings.) locking one or more rings in place. If this is the case then I'm afraid you'll need a new piston or barrel and piston kit.

I'm hoping that you will be lucky and damage will be minimal but any 'Valve Event' tends to be costly and it is very important to find out why it occurred. Just fixing it up is a recipe for a repeat event!

Found this which might be cheaper?

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I like this picture, looks like an arrow in the middle of the cylinder head informing the Guzzi mechanics which way round it fits, exhaust gases goes that way

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