Alfa Romeo Forum banner

1 - 13 of 13 Posts

·
Registered
Joined
·
24 Posts
Discussion Starter #1
Through my own idiocy I forced a valve follower in. Now it's stuck about 1/8" from where it should return to. The cam can push it down, but it won't come back up (I've pushed the car around sending oil in, still nothing). Piston doesn't hit or anything. Any suggestions?

I don't even care if it ruins the follower, I just want it out. Preferably without removing the head again though, since I'd have to buy another head gasket...
 

·
Registered
Joined
·
3,813 Posts
It is not a good sign that it is stuck, as you would have thought the immense power of dual valvesprings would push it up! So I guess it doesn't spin either?
Did you replace the old followers in their original ports, as you should have?

Personally, I would take off the cam, and try pushing down on the follower with a short strong round wooden block, or tapping the block with a mallet, whilst someone squirts thin oil in there, or maybe wd40 or something. Make sure the piston on that cylinder is down though, not at tdc.
 

·
Registered
Joined
·
24 Posts
Discussion Starter #4
72 spider 2L

Followers are back in their original bores. When I was installing it, I did notice that the bore had a couple small nicks, but I didn`t think that was anything overly bad. I *think* the top of the tappet is getting caught on those nicks.

I`ll try the tapping thing, was also thinking about using the cam to push it down fully, then running a piece of emory cloth around in the bore to smooth it out (then if it works, remove all, clean out bits of alum. ).

I just really don`t want to have to remove the head again. New gasket+removing exhaust manifold+carbs+lifting again makes me want to cry.
 

·
Registered
Joined
·
3,480 Posts
I have rebuilt hundreds of these engines,i can't see how the follower can be 1/8 of its travel down ,(even with an ally nick),with the power of the spring pushing it up.No offence intended but are they shimmed up right.Also if they are and the valve is really that far down there is no way that you have turned the engine over and the piston hasn't touched that valve.:)
 

·
Registered
Joined
·
24 Posts
Discussion Starter #6
I have rebuilt hundreds of these engines,i can't see how the follower can be 1/8 of its travel down ,(even with an ally nick),with the power of the spring pushing it up.No offence intended but are they shimmed up right.Also if they are and the valve is really that far down there is no way that you have turned the engine over and the piston hasn't touched that valve.:)
They are shimmed, but not to the correct value. (I installed new valves, so I just put the cams on to gap, and this happened). I may have overstated it. When the valve is free (no cam lobe pushing), the follower becomes about level/just below the rim of the bore. That's why I estimated maybe 1/8" down (like all the others when they pop up).

You have got me curious wondering if maybe the shim fell off when I knocked the follower in? I'm not sure if it would be thick enough to make this much of a difference, but I'll put cyl 3 at TDC tomorrow and look at what's going on.
 

·
Registered
Joined
·
24 Posts
Discussion Starter #7
Alright. So I checked it out. The piston was not hitting it, but the valve was indeed stuck open. Guess I exaggerated the amount, but I could always see it open looking down the spark plug hole.

Took off the cam, gave it a tap and first hit it popped back up to fully extended position (valve closed). However, could not spin it, nor remove it. Put the cam back on, and started rolling the car back and forth while letting the oil soak in. Now it doesn't get stuck, it's moving up and down freely, but it still won't spin, so I assume it won't be removable yet. And no, no miracles, it's gapped at 0.017 (exhaust), so I DO need to change the shim.

Any suggestions on removing a follower? It's at the standard position like most, but won't spin or anything. My harddrive magnet (NIB, rare earth) can't pull it, nor can I twist it.
 

·
Registered
Joined
·
3,813 Posts
Well good to hear that my tip to give it a good clout freed it up!....always worked for me!

Probably obvious, but have you tried a suction cap (like the type you must have used to grind-in and lap the valves)?
If you do get it out i would do a visual investigation why it got stuck in the first place, but once you have correctly reshimmed it, it should be OK now!
 

·
Registered
Joined
·
24 Posts
Discussion Starter #9
Well good to hear that my tip to give it a good clout freed it up!....always worked for me!

Probably obvious, but have you tried a suction cap (like the type you must have used to grind-in and lap the valves)?
If you do get it out i would do a visual investigation why it got stuck in the first place, but once you have correctly reshimmed it, it should be OK now!
I had a couple burnt valves, so I just replaced all the valves. No lapping was done. The seats seemed to be in good shape and I didn't really have access to tools or a machine shop on cheap, so I just left them and hoped for the best.

So no, I don't have a good suction cup...I'll try to find one, but I don't think I'll get one that has more pull than a NIB magnet..

Worst comes to worst I destroy the follower by grabbing it with vicegrips/drill and just buy a new one, but I'd prefer to not have to spend $30 on something like that.
 

·
Registered
Joined
·
3,813 Posts
If you do end up destroying the old follower, try not to destroy it so much that you cant get a micrometer to it to measure the thickness at the centre, as you will need this and the thickness of the old shim to evaluate the new shim size with a new follower!
One thing though, you really should have ground in the valves, even new valves need thorough grinding in to properly mate with the old seat surface/angle etc....lets hope for the best you are OK on this one!
 

·
Registered
Joined
·
24 Posts
Discussion Starter #11
If you do end up destroying the old follower, try not to destroy it so much that you cant get a micrometer to it to measure the thickness at the centre, as you will need this and the thickness of the old shim to evaluate the new shim size with a new follower!
One thing though, you really should have ground in the valves, even new valves need thorough grinding in to properly mate with the old seat surface/angle etc....lets hope for the best you are OK on this one!
I know, I'm kicking myself here. Really not sure why I didn't. But in the end I didn't so hoping for the best.

Main goal is to get it running again, I can worry about all that later I suppose. Not much I can do now with the head back on.

--

I was under the assumption the followers were all spec-ed almost perfectly in terms of thickness? (Paraphrasing from Pat's book if I remember right).

Or is that new followers only? Will record the numbers and see. Thanks. Any idea what the thickness is for new cups?
 

·
Registered
Joined
·
3,813 Posts
new followers are probably spec-ed, but old ones can get pretty worn as they are (normally!) able to spin on the shims, so they wear down here on the inside, and the cam whacking it wears it from the top!
I tried a new valve once in a newly ground valve seat with new springs with the petrol/gasoline test (pour a bit of gas down the back and see if it leaks through to the combustion chamber!), and the petrol just leaked through, even though it looked perfectly tight to me. When i ground it properly, absolutely nothing leaked through.
I dont know what the thickness of new followers are. Maybe someone here on AO has a new one that they can check for you with the micrometer?

i was thinking of how to get out the follower: what about using a 2 component glue and glueing something like a big nut to the surface, then screw a bolt into the nut and try that way to pull and twist it out? (obviously thoroughly degreasing the follower surface)...this way you could save the follower, as the glue will come off.
I had thought of spot welding something to the follower, but the heat would do some damage somewhere for sure.
 
1 - 13 of 13 Posts
Top