Valve seals tore on break in

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standup303

standup303

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Hey all, I just broke in my 440 which went great except for it tore the tops off 3 valve seals….so far. I had some small pieces laying in the heads. I’m not worried about the blue rubber, I am worried about these tension springs/bands that are now riding on my valves and their potential to break and get into the crank case.

What should I do?

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you are 1000% not going to want to hear this... but you need to fix that and to fix that, you're going to have to figure out why they got all tore up. which... could mean pulling the heads and checking/changing the seals or machine work to make everything work properly.

start by checking your retainer clearance, then make a determination from there.

eta: you may also not have enough clearance on the inner spring; and that's what was grabbing them. so something else to throw into the considerations.
 
junkyardhero said:
you are 1000% not going to want to hear this... but you need to fix that and to fix that, you're going to have to figure out why they got all tore up. which... could mean pulling the heads and checking/changing the seals or machine work to make everything work properly.

start by checking your retainer clearance, then make a determination from there.

eta: you may also not have enough clearance on the inner spring; and that's what was grabbing them. so something else to throw into the considerations.
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Clearance from the seal to the inner spring is very tight. It seems the top just tore. I didn’t like those damn springs/bands from the get go I knew I should have left them off.
 
standup303 said:
Clearance from the seal to the inner spring is very tight. It seems the top just tore. I didn’t like those damn springs/bands from the get go I knew I should have left them off.
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having gone thru this in the not too distant past, i know the frustration. in my case it was the keepers and retainers that tore up the top of the seal. an annoying but fairly straight forward fix.

i don't know how much of the work you do yourself, but key to this here is the correct machine work for the seal and vice versa.

so i'd run it back and be sure you're machined for that type of seal, and then double check all the critical tolerances and make sure you don't have contact from any of the components there.
 
As was asked, did you lube the stems? Also, did you use the small valve stem "condom" that fits over the end of the valve stem and protects the seals from the sharp edges of the tip of the stem? Pretty important. Lastly, in that first picture, it certainly looks to ME like the blue material the seal is made of is dry rotted. As if it has sat on the shelf a long time. It looks to me like that's your cause. If you didn't use the little valve stem tool, that certainly didn't help.
 
RustyRatRod said:
As was asked, did you lube the stems? Also, did you use the small valve stem "condom" that fits over the end of the valve stem and protects the seals from the sharp edges of the tip of the stem? Pretty important. Lastly, in that first picture, it certainly looks to ME like the blue material the seal is made of is dry rotted. As if it has sat on the shelf a long time. It looks to me like that's your cause. If you didn't use the little valve stem tool, that certainly didn't help.
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I didn’t use the little valve stem tool. I didn’t have one. Dammit man! The rubber didn’t feel dry or cracked. But who knows.
 
Bewy said:
[1] Were the stems/seals pre-lubed?
[2] Could they be 11/32" valve seals, BB uses 3/8" valves?
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Well I pre lives the valve shafts with WD 40 but not assembly lube. Just double checked and they are 3/8 seals. And we’re not difficult to install over the valves.
 
Pull the heads and take them to a machine shop. That would be the only correct fix. Your head needs to be machined for the larger lift cam and the retainers you are using. The retainers squashed the seals. Common problem that many do.

Clearancing things is part of an engine build . You my friend skipped a critical step. What else was skipped over? That would be your next question to asked yourself.

Like did you seat the thrust bearing. Did you check the rotation torque. All critical for engine building plus many more procedures to make them last for many miles. Did you clearance the Cam bearings ? Many don't. Things you should be asking yourself.

The most critical is balancing. You don't know how many pro balanced rotating assemblies that come in that are over 80 grams out. Molnar stroker kit for a Ford FE Pro balanced? 128 grams out. Never trust anything you buy.
 
Oldmanmopar said:
Pull the heads and take them to a machine shop. That would be the only correct fix. Your head needs to be machined for the larger lift cam and the retainers you are using. The retainers squashed the seals. Common problem that many do.

Clearancing things is part of an engine build . You my friend skipped a critical step. What else was skipped over? That would be your next question to asked yourself.

Like did you seat the thrust bearing. Did you check the rotation torque. All critical for engine building plus many more procedures to make them last for many miles. Did you clearance the Cam bearings ? Many don't. Things you should be asking yourself.

The most critical is balancing. You don't know how many pro balanced rotating assemblies that come in that are over 80 grams out. Molnar stroker kit for a Ford FE Pro balanced? 128 grams out. Never trust anything you buy.
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This sounds like what likely happened. Plus, I'm standing by what I think about those seals. They look rotten to me. I think @Oldmanmopar's suggestion is probably right on the money.
 
OMM knows of what he speaks, I too have had the same problem on my SBM heads. My machinist fixed the problem that I should have had corrected before I assembled the heads.
 
Demonracer said:
OMM knows of what he speaks, I too have had the same problem on my SBM heads. My machinist fixed the problem that I should have had corrected before I assembled the heads.
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What did he do to correct it? Machine the guide bosses down and use a shorter seal?
 
The guides were machined correctly for the seals and we added the correct springs, keepers and retainers. Other than freshening up the heads over the years, the seals have done their job @pittsburghracer can probably put his suggestion.
 
Demonracer said:
The guides were machined correctly for the seals and we added the correct springs, keepers and retainers. Other than freshening up the heads over the years, the seals have done their job @pittsburghracer can probably put his suggestion.
Click to expand...

Just looking at the pictures im
Not going to add my 2 cents on stock heads. Just to many variables that need checked and addressed before using that seal. I will say it’s important to use the right tool and I soak mine in oil before installation.
 
It could be something else but whenever I have seen this it was from the retainer contacting the seal. One time I saw a seal that didn't get installed correctly (all the way down on the guide) which then caused the retainer to contact the seal and chew it up. I would check the retainer to guide clearance before you tear it apart. If you haven't removed the seals that are damaged inspect the to see that they were installed properly ( all the way down).
 
Well they had to have been machined for those seals to fit. Sometimes when those seals are installed they can get crooked on the guide, which I can take a guess someone could have used a socket to correct that & it pinched the top.
2.
Other thing is guide height and possible keeper contact but by the looks of the photos I'd guess a variation of the 1st part.

I always take a file to the stem directly above keeper grooves because usually there's burrs or something, that gets filed down smooth again
(don't remove too much).
I never use those plastic seal installers deals unless I am installing the hard 100% Teflon seals.
Because it's necessary with the tension rings.
 
MOPARMAGA said:
Well they had to have been machined for those seals to fit. Sometimes when those seals are installed they can get crooked on the guide, which I can take a guess someone could have used a socket to correct that & it pinched the top.
2.
Other thing is guide height and possible keeper contact but by the looks of the photos I'd guess a variation of the 1st part.

I always take a file to the stem directly above keeper grooves because usually there's burrs or something, that gets filed down smooth again
(don't remove too much).
I never use those plastic seal installers deals unless I am installing the hard 100% Teflon seals.
Because it's necessary with the tension rings.
Click to expand...
Yup, installed with a socket, like an idiot.
 
Not beat the OP, but the BFH should be reserved for other things. Just making light of the situation, not trying to rag on anyone.
 
MOPARMAGA said:
Well they had to have been machined for those seals to fit. Sometimes when those seals are installed they can get crooked on the guide, which I can take a guess someone could have used a socket to correct that & it pinched the top.
2.
Other thing is guide height and possible keeper contact but by the looks of the photos I'd guess a variation of the 1st part.

I always take a file to the stem directly above keeper grooves because usually there's burrs or something, that gets filed down smooth again
(don't remove too much).
I never use those plastic seal installers deals unless I am installing the hard 100% Teflon seals.
Because it's necessary with the tension rings.
Click to expand...
Not necessarily. The guide OD stock is 5/8" and there are seals available to fit that.
 
MOPARMAGA said:
Yeah that's true, I never install a seal on a stock guide though.
What part is not necessarily in your opinion???
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Having to cut the guides. It's not necessary on everything, but you need to CHECK on everything.
 
RustyRatRod said:
Having to cut the guides. It's not necessary on everything, but you need to CHECK on everything.
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I suppose that's true. I work at a machine shop, so I do it anyway. Old cast iron heads weren't machined close most of the time so I like to set everything where it is equal & usually cut .100 off the top of the shortest , then match the rest. I also cut the guides od to .502 on all cast iron heads. The new guides I install are that size. I also check what cam lift is just so the clearance is there.
 
MOPARMAGA said:
I suppose that's true. I work at a machine shop, so I do it anyway. Old cast iron heads weren't machined close most of the time so I like to set everything where it is equal & usually cut .100 off the top of the shortest , then match the rest. I also cut the guides od to .502 on all cast iron heads. The new guides I install are that size. I also check what cam lift is just so the clearance is there.
Click to expand...
I used those same seals on my slant 6 head and I still have a LOT of room between the guides and retainers. You probably weren't thinkin about a slant 6, though. lol

BUT, I did use 318 valves for some valve spring. They are .300" longer than slant 6 valves.
 
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