Possible valve-train repair

[garhett]

Hey guys, Feels like I been posting a lot lately, but I could really use some advice on this one

So I have a great mechanic I visit once in a while. He works particularly on European sports cars and Fiats. He's given me a LOT of help and advice. Most of it free.

Long story short, the car (77 1800) has had a good tick for a while now. Doesn't matter what RPM and is %100 coming from the top end. Checked the valve clearances everything tight. So he's guessing most likely it's something in the valve-train. Either a spring, bucket, or maybe even a guide.
I guess if I'm lucky it could be the bucket or spring on top and I can get to it from the cam box, if I'm not lucky...Head Gasket

So!... My questions are:

1. What are the chances ( if any ) that I can fix the problem with pulling the cam box?

2. what causes these parts to fail? fatigue?

3. I've heard Head Jobs on these things actually isn't something to run screaming from. I tried doing a little research and couldn't quite find a thread just on doing a valve job. I Have the Actual Fiat Dealership manual so I'm pretty confident, but inexperienced.

Thanks guys!

[124JOE]

if its a head gasket then a leak down test

if its one of the others then you can locate it with a long screwdriver
and your ear,just place it on the spot you think its comming from while running
then poke around on the motor and listen you will find the problem area

[garhett]

if its one of the others then you can locate it with a long screwdriver
and your ear,just place it on the spot you think its comming from while running
then poke around on the motor and listen you will find the problem area

That's actually what we did.

Leak down test, sorry I'm not actually sure what that is. I was only bringing up the head gasket because I would need to replace it and such correct?

[So Cal Mark]

you may have a broken valve spring and that can be replaced without removing the head. The only reason to pull the head for cam related repairs would be if you have a valve guide that is worn out. A valve job on these heads is no different than any other car

[garhett]

you may have a broken valve spring and that can be replaced without removing the head. The only reason to pull the head for cam related repairs would be if you have a valve guide that is worn out. A valve job on these heads is no different than any other car

Great, you made my day! Well I've never actually done a valve job though.
I couldn't find any threads on it, if you guys know of a good one that would be great if you could link it!
Do I need to pressurize the cylinder to work on that?

[BEEK]

intermitant valve tick: a fiat story,
having run across this problem a few times in my fiat career, i decided to take a basket case which a valve tick would come and go, sometimes tick tick tick, others smooth. pulled the head and dissasembled and measured everything. found 2 causes.

1. the valve stem head was worn or not machined flat, this with a worn lifter seat, as the valve rotated (yes they do) as the engine was running, the valve clearance would actually change. causing the tick to come and go. i have adjusted valves on a head rotated the cams a few times and the clearance chad changed, readjusted, and rotatted again, and guess what, the clearance changed.

2. worn valve guides, this will allow to valve to rock side to side in its seating area on the follower, again the old follower will have a wear area and a small ridge, this will again cause valve clearance change.

3 as to broken valve springs, i have never seen broken oem valve springs on a fiat, performance aftermarket ones yes, but never oem.. just my personal observations.

4 btw after correcting this, the tick went away, never to return

[garhett]

O, something else I wanted to ask. I don't really have a place to work on this thing now, I'm sure I could find something if I needed but time's a little short.
I'm about to move home at the end of the week and the drive is 1,500 miles. The mechanic said worst case scenario is that the valve could actually fall out into the cylinder. Anyone ever had this happen, or whats a more likely scenario if something did go wrong?

[manoa matt]

One thing that hasn't been mentioned yet but also makes a ticking noise commonly misdiagnosed as valve noise is a failed or failing exhaust manifold gasket. Get a 3-4 foot length of hose and hold one end to your ear while moving the other end around the area of the gasket while the car is running to listen for the tick.

[So Cal Mark]

I agree about the exhaust leak, but I assumed since an experienced Fiat mechanic was somewhat involved that it had been checked. I also haven't seen a broken valve spring on a Fiat, but that doesn't mean it can't happen