Reproduction Parts for 1916-1964 Chevrolet Passenger Cars & 1918-1987 Chevrolet & GMC Trucks


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Morten Offline OP
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Finally got my "new" head a few weeks ago.
It looks good, and has been pressure tested with success.

I got it with valves installed, and some could easily be removed, other needed a few days with WD40 and light knock with hammer.
But I have 4 valves I can`t get to loosen up, I have on daily basis sprayed with WD40 and other light oil for 2-3 weeks, but they are still completely stuck.
What is the best way to get these valves out?

As it`s been almost impossible to find a good head, I don`t want to risk damaging it.

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I have had good luck separating rusted knee shock absorber pistons and other parts using "PB Blaster" and a little heat and tapping gently with a hammer and a light touch. I would be careful not to overheat the part. Repeat the process, it may take a few times. Be patient and it might loosen up for you. Good luck

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If the valves are rusted to the guides you may need to press out the guides and install new guides and valves. In fact it looks like all the guides will need to be replaced and possibly the valves also due to rust to prevent future problems.


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agree with Gene, when i had my head done a local shop replaced all the guides, and replaced a few valves. the guides were cheap !! and well worth it. i had them tear it down magnaflux it, they did a complete rebuild and machined all mating surfaces, re seated al the valves, and then put it all back together like new. then pressure testes and validated all valves worked and were set the same wink the total cost was cheap and well worth it.


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Morten Offline OP
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I`ll replace all valves and guides, so not trying to save them.

Guides would normally be pressed out from the underside, because wide end is in top, and here guides small end can`t be put under pressure from the underside, because of the valve head.
Do you cut the wide end of the guide just above collar/washer, and press it the "wrong" way out?

I know I could leave all this to machineshop, but I better understand and remember things by doing them myself.

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once you remove the valves the valve guides can be easily pressed out from underneath. clean clear shot :) tool & press

Few shots of spare head sitting on my shelf.

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Morten Offline OP
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Yes, valve guides are easy to press out from underneath once valve is removed.
My problem I can`t get the last 4 valves free, even after 3 weeks of daily oiling with WD40 and other light oilproducts.

I`ll replace valves and guides, so it`s just a matter of not damaging my hard to find 1932 head, so don`t want to use to high pressure or hard tapping with hammer.

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Have you tried rotating the valves to help free them up?


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if you are going to replace valves and guides anyways, cut the stem off at the guide and drill it out, then press out the guide. other option is use an annular cutter and remove the valve head and then punch stem through with the guide.

worst case, have a local shop knock em out.


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Hi Morten

Why not just put the head in a press, valve stem side up (as it is on the engine),
support the bottom side of the head as close to the valve you are working on as possible,
then press directly on the end of the valve stem?

Make sure you have completely cleaned the exposed part of the valve stem with emery cloth.

You should be able to press with as much force as would be needed to press the guide out of the head, without hurting anything.
That's a lot of force, but it is after all the same force that any shop will use if and when they actually replace the guides.
And that force will be taken on the guide (just as it will when removing the guide) until the valve breaks loose.

If the valve still doesn't want to move,
maintain as much press force as you dare on the end of the valve,
then use a large torch to rapidly heat the exposed part of the guide and the valve should pop loose.

Once the valve is broken loose,
make sure there is no "mushrooming" on the end of the valve stem from pressing or hammering.
If there is,
grind it off before trying to complete the removal of the valve so it won't stick in the guide on the way through.

Hope this helps!

PS
If your valve heads are recessed below the bottom face of the head as I think they are,
you can support the full face of the head until the valve breaks loose.
That should help insure that no damage is done to the head during the process.

Last edited by Stovblt; 06/25/22 10:14 PM.

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I should add that constant force, even if it is a LOT of force, will be much safer for your head than sharp hammer blows.
Also, if you are really lucky, you may not destroy the guide in the process, and actually be able to clean it up and use it as is.


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Thanks for all your inputs, I tried a little of everything.

First tried to rotate the valves, it was impossible.
Then I cut the wide end of one guides, tried to press out the valve in my 20 ton press, didn`t move.
I drilled out the valve stem about half way trough guide length.
As I don`t have a stand, I had to do it in free hand, so was not sure enough of angel to drill all way through so stopped halfway.
Still couldn`t press valve out.
Turned head around, and grinded the head off the valve, pressed on the remaining stem, still no succes.
Turned head back to normal position, drilled hole a bit wider, and finnally I could press the short stem part out, but only because it at the same time broke a bit of the guide of.
On the next 3 valves I cut the stem, so it was only slightly over the guide, and they all gave up a lot easier in the press.

So I just started with the hardest valve to get out, if I had started with one of the other, I might not have been so concerned about damaging the head.

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that is all good news....

so it is completely torn down ? minus the valve guides. regardless i would have all new valve guides put in especially if you are doing new valves !!
also if you plan to reuse springs have them tested to make sure they are all good


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2 of the guides cracked and went into several parts when I removed valves, so them seem fragile, and will all be replaced.
I expect all guides to come out pretty easy, but will see in the next few days.

Didn`t you make a thread some time ago, about spring load and length?

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After 3 months at the machine shop I could finally pick up my machined head (+ rebored block, new pistons and other extra parts), so I was very happy, until I unpacked all the machined parts.

The head has got a lot of work done, including new seats at all exhaust valves.
At least 3 of the new seats have caused cracks in chambers, see pictures.

I didn`t notice it at the shop, so haven`t talked with them yet, but when I picked up the parts, they claimed head was pressure tested.
I`m not sure at which state this pressure test was done, but is it possible to have these cracks without getting lots of bubbles at pressure test?
All cracks run from exhaust seats and down towards the chamber in front of sparkplug.

This is my 3 cracked 1932 head, so I`m not very happy right now, and it doesn`t help that this one head has already cost me more than 1500$, and as most of you know it`s so hard to find 1932 heads.

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are the cracks surface cracks ? or cracked through ?

my head was pressure tested was when it was completed

I would call them/go up there and just ask them about the cracks, and express your concerns. see what they have to say before jumping wink

what did they do for $1500


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I beleive also it was tested after they finished the work, but have to ask.

Cracks might be in surface now, but hard to tell what will happen when engine is all put together, so not to happy about using it, even if it`s tight now.

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see if they have a warranty/guarantee ??

tell them your concerns, my shop that did mine said if any issues bring it back no questions. so far no issues on mine. they guarantee their work wink


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Had the same problem with my '32 head. "hairline" cracks around valve seats. Engine was completely rebuilt and water drained to oil pan just sitting. Fortunately the shop stood behind their work. Found a local gentleman with a ton of old Chevy parts and he had a new unused head (really) which is on the car now and it runs perfect. The cracks on yours appear bigger than what I had and mine leaked.


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I first called the shop and talked with them, and they claimed the cracks were no problem, as the material in that area is over 1 inch thick, and they had done a pressure test without leaks.
I couldn`t beleive there should be so thick walls, so I took a 1929 head which was already scrapped and cut it in 2.
In picture you can see the cracked area marked red, and the black/white is the part you can`t see, but must expect to have cracks as well.

I then took my 1932 head and the cut head to the shop, and they accepted to do a new pressure test while I was still there, and it showed that all 3 cracks are all the way through the material, so can`t be used as it is now.
Shop will check if it can be fixed in any way, but i`m not to possitive, as they might succed to repair cracks for now, but what will happen when head is exposed to pressure and heat when in use.

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There are a few methods to repair a cracked cylinder head. Do a goggle search for the info. I would advise to have it done by a shop that is experienced in doing so and it appears that the shop you have now is not competent for the repair. It really needs to be done by an experienced shop and not all heads can be repaired. The process I am most familiar with is pinning or some call it stitching. If done properly and on a repairable head it should give work as good as any rebuilt head.

Last edited by m006840; 10/06/22 07:56 PM. Reason: spelling error

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also note they must be knowledgable and experienced in dealing with cast iron !!


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Originally Posted by m006840
The process I am most familiar with is pinning or some call it stitching.

This is also what they are looking at, but problem is to find some with the knowledge, and i`m concerned about the area i`ve marked with black/white, as you can`t access it for stitching.

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From the pictures of the cut cylinder head there doesn't seem to be much "Meat" to cut away for the new valve seat install before hitting the water jacket. I would think one would have to be careful when installing a new seat, was told of this by several automotive machinists in years past.

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Originally Posted by Master Six
From the pictures of the cut cylinder head there doesn't seem to be much "Meat" to cut away for the new valve seat install before hitting the water jacket. I would think one would have to be careful when installing a new seat, was told of this by several automotive machinists in years past.

Correct, that was exactly what happend to the original head.

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