Help! Can't remove valve keepers

[Mark E.]

My weekend project was to renew the valve seals on my '70 454, but I'm stuck. Or rather the valve keepers seem to be stuck in the spring retainers. With 80 psi of air in a cylinder at TDC, when I compress the valve spring the entire valve assembly just opens and releases the air. I tried this with four different valves on two cylinders with the same result.

Should I apply more air pressure to keep the valve closed? The manual doesn't specify how much air pressure, so I thought 80 psi (which would put about 240 pounds of force on the valve face) should be enough.

Is it a good idea to rap the top of the spring retainers with a socket and hammer to jar the keepers? (I haven't tried that.)

I haven't done this before so I don't know what to expect.

Thanks in advance for your help.

[Joe L.]

Re: Help! Can't remove valve keepers

Is it a good idea to rap the top of the spring retainers with a socket and hammer to jar the keepers? (I haven't tried that.)



.

Mark------


Absolutely YES. Several sharp, HARD raps. You're not going to damage anything.

[Patrick H.]

Re: Help! Can't remove valve keepers

Interestingly enough I'm doing this project as well.

I had to bump up to 120 psi to get the valve not to drop, even with rapping it.
After many years the seal will stick to the spring retainer and be a chore to remove.

[Steven B.]

Re: Help! Can't remove valve keepers

Mark, like Joe and Patrick said. Had to go to 120 or 130 psi and tapped hard with ball peen multiple times. Good Luck!

[Mark E.]

Re: Help! Can't remove valve keepers

Thanks guys. Tomorrow, I'll give them a good wack and push up the air pressure. Wish me luck.

[Joe L.]

Re: Help! Can't remove valve keepers

Interestingly enough I'm doing this project as well.

I had to bump up to 120 psi to get the valve not to drop, even with rapping it.
After many years the seal will stick to the spring retainer and be a chore to remove.

Patrick------


I assume you're talking about a small block. Big blocks use different type valve seals and the condition you describe is not created.

[Patrick H.]

Re: Help! Can't remove valve keepers

Patrick------


I assume you're talking about a small block. Big blocks use different type valve seals and the condition you describe is not created.

Yes it is.

[Joe L.]

Re: Help! Can't remove valve keepers

Yes it is.

Patrick------

By the way, some folks think of stock small block valve seals as being "o-rings"; they are not. The stock seals have a rectangular cross section and not a round cross section. In addition, if stock seals are used, only use those that are Viton material. NEVER use seals of any other type material.

[Mark E.]

Re: Help! Can't remove valve keepers

Update:

I finished two valves! Increasing air pressure to 100# and rapping the spring retainers with a 3# hammer through a socket loosened the keepers. That took over two hours this evening; now only 14 valves to go...

The budget pry-bar style spring compressor interfered with the carburetor. So I bought another spring compressor from Proform that screws onto the rocker stud. This also made the job easier by keeping the spring compressed while I used both hands to remove/install the keepers.

Now I wonder if I'm using the proper replacement valve seals. I got Fel-Pro SS 72513. They're made with a hard, white nylon material and look different than the old ones (black, rubber like material with metal bands). The first photo shows the remnants of the old seal next to the new Fel-Pros.

Are these an improved design? Or did I get the wrong seals? They fit perfectly.

The second photo shows what I saw when I lifted off the spring. Not much left of the old seal. This is an engine that was rebuilt 23 years ago with about 8,000 miles.

[Joe L.]

Re: Help! Can't remove valve keepers

Update:

I finished two valves! Increasing air pressure to 100# and rapping the spring retainers with a 3# hammer through a socket loosened the keepers. That took over two hours this evening; now only 14 valves to go...

The budget pry-bar style spring compressor interfered with the carburetor. So I bought another spring compressor from Proform that screws onto the rocker stud. This also made the job easier by keeping the spring compressed while I used both hands to remove/install the keepers.

Now I wonder if I'm using the proper replacement valve seals. I got Fel-Pro SS 72513. They're made with a hard, white nylon material and look different than the old ones (black, rubber like material with metal bands). The first photo shows the remnants of the old seal next to the new Fel-Pros.

Are these an improved design? Or did I get the wrong seals? They fit perfectly.

The second photo shows what I saw when I lifted off the spring. Not much left of the old seal. This is an engine that was rebuilt 23 years ago with about 8,000 miles.

Mark------


This engine has had the valve seals replaced with non-stock type rubber seals. It's also had the valve guides replaced, at least on this valve position. It's also had the springs shimmed.

This type rubber valve seal will not work well with original dual springs (assuming the engine still has original valve springs). There is insufficient clearance between the inner spring ID and the valve seal OD. That may be at least part of the reason that the valve seal pictured broke apart.

The valve seals you purchased are the ones that should be used PROVIDING that the valve springs are original dual springs, the valve spring caps are original to the engine and the valve guides are original OD. Original valve spring caps, GM #3964264, usually have a "U" debossed on the top. However, from what I can see of them, these do not appear to me to be the original valve caps. The seals you purchased can only be used with the original valve caps.

For all 1965-72 big blocks, I recommend that only dual spring valve springs (supplied as part of unit GM #3970627) and valve spring cap with seal GM #3964264 (also included with 3970627 unit) be used. Unfortunately all of these parts are discontinued without supercession.

Are your valve springs dual springs without flat dampner? What is the OD of the valve guides? Please picture the valve spring caps, top and bottom.

[Joe L.]

Re: Help! Can't remove valve keepers

This is what the GM #3964264 valve spring cap with seal looks like. These were used on all L69-72 big blocks except L-88/ZL-1. With the associated dual valve spring they are SERVICE for all 1965-72 big blocks except L-88/ZL-1.

[Mark E.]

Re: Help! Can't remove valve keepers

Joe,

Thank you for your help with this. Below are some measurements and photos.

Retainers- Based on your description, the two retainers I removed may be GM #3964264?. Each has a faint "U" embossed on top (see last photo). And the new Fel-Pro seal snaps onto them like the original design (see first photo).

Old Springs- These have a flat inner spring captured (won't come out of) inside the outer spring. The free length of the two I removed are 2.070' and 2.100". The service manual specifies 2.12". Their ID is 0.990" which provides lots of clearance for the seal. They are in the foreground of photos 1, 3, 4.

New Springs (Speed Pro VS-708)- These have a round inner spring that easily slips in/out of the outer spring. The free length of the 16 I bought range from 2.152" to 2.166". Their ID is 0.795" which is 0.025" less than the OD of the seal (0.012" clearance). The second photo shows a new seal placed inside the new spring.

I bought new springs as insurance. Several years ago, one broke which was replaced individually.

Guides- The OD of the two guides from the cylinder I'm working on are 0.620" and 0.630" (both look like replacements). This is 0.060" to 0.070" less than the ID of the seals.

What do you think? I'm open to getting different springs or other hardware as suggested to get this done right and once.

Valve Guide OD: 0.620", 0.630" (#6 Intake, Exhaust)
Old Inner Spring ID: 0.990" (Flat Inner Spring)
New Inner Spring ID: 0.795" (Speed Pro VS-708; Round Inner Spring)
Valve Seal OD: 0.770" (Fel-Pro SS72513; set of 16 90763 Nylon Seals)
Valve Seal ID: 0.690"

[Joe L.]

Re: Help! Can't remove valve keepers

Joe,

Thank you for your help with this. Below are some measurements and photos.

Retainers- Based on your description, the two retainers I removed may be GM #3964264?. Each has a faint "U" embossed on top (see last photo). And the new Fel-Pro seal snaps onto them like the original design (see first photo).

Old Springs- These have a flat inner spring captured (won't come out of) inside the outer spring. The free length of the two I removed are 2.070' and 2.100". The service manual specifies 2.12". Their ID is 0.990" which provides lots of clearance for the seal. They are in the foreground of photos 1, 3, 4.

New Springs (Speed Pro VS-708)- These have a round inner spring that easily slips in/out of the outer spring. The free length of the 16 I bought range from 2.152" to 2.166". Their ID is 0.795" which is 0.025" less than the OD of the seal (0.012" clearance). The second photo shows a new seal placed inside the new spring.

I bought new springs as insurance. Several years ago, one broke which was replaced individually.

Guides- The OD of the two guides from the cylinder I'm working on are 0.620" and 0.630" (both look like replacements). This is 0.060" to 0.070" less than the ID of the seals.

What do you think? I'm open to getting different springs or other hardware as suggested to get this done right and once.

Valve Guide OD: 0.620", 0.630" (#6 Intake, Exhaust)
Old Inner Spring ID: 0.990" (Flat Inner Spring)
New Inner Spring ID: 0.795" (Speed Pro VS-708; Round Inner Spring)
Valve Seal OD: 0.770" (Fel-Pro SS72513; set of 16 90763 Nylon Seals)
Valve Seal ID: 0.690"

Mark------


The existing valve springs (single coil with dampener) are definitely not the original valve springs that were supplied on your engine. Someone changed the originals for the ones you have now, probably in order to use the rubber positive seals. Positive seals such as the ones you found on the engine as well as conventional umbrella seals (as used for all 1965-E69 big blocks except L-88/ZL-1) will not work with the L69-72 dual valve springs due to insufficient clearance between the inner spring ID and valve seal OD. So, in order to use the rubber positive seals, someone converted to the 1965-E69 style valve springs. GM did not change to the dual spring for L69-72 because the 65-E69 springs worked just as well. As a matter of fact, the 65-E69 springs are very prone to breakage, although I don't know if the aftermarket versions (which is likely what you have) were the same in this regard to the original GM springs.

The VS-708 valve springs are identical to the original springs used for L69-72. I confirmed this a long time ago. In fact, Federal Mogul/Speed Pro specify that these valve springs MUST be used with the 3964264 cap/seal assembly. However, this assembly was never supplied through or offered by Federal Mogul/Speed Pro. This was a GM-only item.

Your valve guides are stock OD.

What you should do is to remove all your current valve springs, remove all of the current seals, install your new Fel-Pro seals in the existing valve spring caps, and install your VS-708 valve springs.

[Mark E.]

Re: Help! Can't remove valve keepers

Mark------

What you should do is to remove all your current valve springs, remove all of the current seals, install your new Fel-Pro seals in the existing valve spring caps, and install your VS-708 valve springs.

Thanks Joe. That's good news for me. And I really appreciate your help.

I'm lucky I have the original style, but not available, spring caps. But what should folks do if they don't have original spring caps? Since they are not available the original style seals cannot be used either. In other words, what combination of NEW springs, seals and caps can be used?

[Joe L.]

Re: Help! Can't remove valve keepers

Thanks Joe. That's good news for me. And I really appreciate your help.

I'm lucky I have the original style, but not available, spring caps. But what should folks do if they don't have original spring caps? Since they are not available the original style seals cannot be used either. In other words, what combination of NEW springs, seals and caps can be used?

Mark------


Without the original valve spring caps, what to do is a problem with no ideal solution:

1) Install the 65-E69 style valve springs. Utilize the stock umbrella seals or positive seals which will install on stock valve guides. This is, essentially, what someone did in your case. However, what they did not do was replace the valve spring caps with the proper ones (which, in your case, has now proven to be a benefit for you). The 3964264 valve spring caps will not properly center the 65-E69 valve springs. One can get by using them (as was proven in your case) but it's really not the right thing to do. If the 65-E69 springs are used, valve spring cap GM #3859909 (stamped "T") , GM #3864900 (stamped "O"), or GM #10069219. Unfortunately, all of these are discontinued, too. There may or may not be aftermarket equivalents.

2) Have valve guides machined to accept all Teflon seals equivalent to Speed Pro ST2019R. Install those seals. Next, install the VS-708 dual valve springs. With these seals and springs there will be adequate clearance between the inner valve spring ID and seal OD. The problem occurs, though, with respect to valve spring caps. I don't know of any available valve spring cap that will properly center the inner valve spring. There may be one available but, if so, I don't know what it is.

3) Install aftermarket valve springs, valve spring caps, and seals which are designed to work together and which have spring rate, open pressure and closed pressure similar to the GM dual springs described above.

I don't like any of these solutions but they are the only alternatives I can come up with.