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Discussion Starter #1
Just when I thought the fun wa

Just when I thought the fun was over.......well, I just found out some more FUN things to do.

It appears that 5 exhaust valves are bent.....shims are about 1/2 inch away from the cam!!!

Questions: Where do I buy a head stud removal tool?......this may take a while, and I would like to have my own.

Do I just replace the bent valves? Or, should I do them all?

The FUN never ends!!!!!!!

Thanks
 
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Discussion Starter #2
Huh? Are you sure? The car w

Huh? Are you sure? The car was running before you took it apart right? Was it running strong or just so,so. When you were doing your service I assume the timing marks were all in the right spots. Did you ever miss a shift? maybe floated the valves at one time? (hard to do on a non hydrulic lifter engine but not impossable)
 
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Discussion Starter #3
Hi Henry,

terrible news.


Hi Henry,

terrible news.

Did you confirm this with a cylinder leakage test?

Personally I would never pull a Ferrari head without pulling all the valves and checking for stem & guide wear and renewing the VG Seals along with checking seat and valve face condition with cutting or relapping in as necc...now if the valves are good, then actually replacing is not necc. imo, of course at some point mileage issues do start to come into play, but on a valve itself stem dimensions/wear and face condition are usually the determining factor.

Sorry to hear this.

Regards, JRV
 
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Discussion Starter #4
Opps forgot...I believe I purc

Opps forgot...I believe I purchased my 4V head wrench from Baum Tools, but it has been a number of years ago.

JRV
 
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Discussion Starter #5
Henry....something doesn't

Henry....something doesn't sound quite right. Could the springs be bound up against something and not "returning"? During your work did you ever.....ever.....turn the crank with the cam belts off? If a valve was that far down...it would seem that the motor would not do a complete revolution of the crank as the pistons would hit the valves. Please provide us with more information....I just can't believe this could be possible.
 
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Discussion Starter #6
I was hoping no one would ask.

I was hoping no one would ask. The car ran great before the major.

Now the truth!!!! I removed the shims on the valves I had to adjust, on the 1-6 bank (about 6 of them). I rotated engine(with the cams), while removing the shims!!!!! I should have replaced the shim, and THEN rotate the cam, before I went on to the next shim!!!!

I even scratched the sides of some of the cam lobes, because, while it hit the shimless valve tappet, the recessed part of the tappet scratched the cam lobe edge.......those lobes are SOFT. A little filing took care of the scratches.

Outside of scratching the cam, I can't see how a shimless tappet can be pushed in enough to cause the valve to bend.......maybe they aren't. However, the tappet, with re-installed shims are TOO far in, like stuck!!!!!.....hence I assumed a bent valve stem.
 
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Discussion Starter #7
It would be tough to bend valv

It would be tough to bend valves, you would definately feel it if turning the motor by hand. Could the shim bucket be "hung up" in some manner and not returning? Something sounds like it could be cocked off perpendicular.
 
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Discussion Starter #8
JRV: I did not confirm this w

JRV: I did not confirm this with a leak down test yet. However, If either the valves are bent, or the shim tappet is stuck, I can't see any other way of checking it out properly, without removing the head.

With the shims 1/2 inch away from the cam, I don't think a leak down is necessary at this point.......too late for that.
 
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Discussion Starter #9
Jeff: I agree with you......i

Jeff: I agree with you......it seems that something may be "hung up"....off center?
 
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Discussion Starter #10
Here's my theory...as the

Here's my theory...as the cam lobe swept across the open shim bucket...it smeared the top lip a little making it "not round" and more. Then it got pushed down into the bore....and due to it's out of round shape it will not return. there must be some way of extracting the lifters? The cams will need to be removed for this of course.
 
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Discussion Starter #11
Jeff: I already removed the c

Jeff: I already removed the cams. It appears that the buckets are stuck.....I can't turn them by hand, as I can the other (non-stuck) ones.
 
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Discussion Starter #12
Henry,

I wouldn't assum


Henry,

I wouldn't assume anything so quickly. While it is possible to bend valves turning an engine/cams over out of time they don't always neccesarily bend from what you describe.

I would back up and do a couple checks and tests first before jumping to conclusions.

First I would rotate the pistons out of the way, half way down, on each problem cylinder in turn, then manualy operate the problem valves open & closed to definatively decipher what you think you are seeing. Then after inspecting and testing each in turn a cylinder leakage test would be in order.

If the above checks/inspections/tests confirm the valves are in fact not seating then you may well have a problem. First things first.

Regards, JRV
 
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Discussion Starter #13
Seems like you two already fou

Seems like you two already found the problem...dang you're fast !!!
 
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Discussion Starter #14
JRV: If we wanted to be "

JRV: If we wanted to be "SLOW", we would have been on that "other" forum.....hahaha

If I turned the cams, without the shims in place, I can't see how the valve could have gone in deep enough to hit the piston and bend.

I will conclude that the bucket is stuck, as Jeff also thinks.

I will now go back, and tap (hit) the buckets with a brass bar, to see if they "pop" out.
 
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Discussion Starter #15
>>I will now go back,

>>I will now go back, and tap (hit) the buckets with a brass bar, to see if they "pop" out.<,

I like to use a hardwood dowel. But if you don't have a hardware store in your garage..

Perhaps we have found a definative answer to why it's not a good idea to rotate Ferrari engines with the shims removed from the buckets.

Regards, JRV
 
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Discussion Starter #16
"Perhaps we have found a d

"Perhaps we have found a definative answer to why it's not a good idea to rotate Ferrari engines with the shims removed from the buckets." How true!!!!!!!

Tapping did no good. I just can't seem to get enough leverage to compress the spring manually.

Looking it over, I can see that the springs are compressed, with the buckets too far in......hence, they are stuck, as Jeff first noted......thanks Jeff.

Solution: ????????????? Remove the head???????
 
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Discussion Starter #17
Pulling the head is certianly

Pulling the head is certianly one option...I think first I would try moving a piston out of the way, all the way out of the way, and with a large dia. hardwood dowel and decent sized heavy hammer try rapping on the cup and letting the compressed spring pressure try to unstick it.

Of course if the cups will not come loose....no way, no how...

{
}

JRV
 
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Discussion Starter #18
Henry,

Those buckets, as yo


Henry,

Those buckets, as you've unfortunately found out do bend fairly easily when subject to side load...as the exhaust side will tend to want to fall out, due to gravity acting on them. When you turned the exhaust cam, without shims in place...the buckets were likely extended out of the head by more than their normal range.

The good new is that there is no need to pull the head to remove them, presuming that there is no valve damage (very unlikely)....

Three possible ways to remove them...

1-Compressed air through the oil gallery beneath the bicket, if possible
2-With a carbide bit, drill a hole of-centre in the bucket...and use a small screw extractor with a puller
3-Carefully tack weld a little stud on the bucket..and use a puller.

A real PIA, but doable with little expensense other than a few buckets...

If you really need it, I have the special head bolt tool for you to use.

Regards,
David
 
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Discussion Starter #19
And...
When you do get the bu


And...
When you do get the buckets out, do a leakdown test to confirm that the exhaust valves were not bent when you turned the engine over, before buttoning everything back up..

Regards,
David
 
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Discussion Starter #20
Is there any place on the shim

Is there any place on the shim bucket that some type of tool could "grab" and using a slide hammer method...pull it back outward?
 
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