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Valve stem seals popping off

26K views 54 replies 8 participants last post by  gapi  
#1 · (Edited)
Ok so im losing my mind over these valve stem seals. When I did my cam swap a few months ago my car started burning oil and found out all 4 valve stem seals popped off and where sitting on the valve stem itself(see pic). I replaced all seals and they all were nice and tight on their spot. Now only a thousand miles later and all 4 popped off again. They're on the passenger side exhaust valves. I used fel pro the first time and I think melling this time.
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#3 ·
They should be, I ordered them from rock auto for my specific car. They also haven't popped off any of the the other 12 valves
 
#5 ·
Yea looking at it it all looks the same and they all use the same seal by part #
I noticed a scratch on two of the valves I checked so far that are closer towards the top but may be just low enough to catch the seal. Idk how it could catch the seal enough to rip it off tho, because they sit on there pretty damn tight.
 
#19 ·
Take cam lift and factor in rocker arm ratio and then with the valve fully closed measure the distance from the scratch to the valve seal. You can use a dial caliber to get close enough to know if the scratch will reach the seal when the valve is fully open.

By this I mean you open the caliper jaws to the lift amount and then hold the one jaw at the top of the seal and see where the other jaw is. If it up past the scratch this is a good sign the scratch reaches the seal. In my opinion that ain't good even if it may not account for the seal coming loose.

Even if the scratch is not why the seal is coming loose if the scratch reaches the seal I'd be worried about the scratch leading to early valve stem seal leakage.

Also, you really should check each valve for proper lift. Maybe you got some wrong rocker arms in the mix? Or even the cam was ground wrong on some lobes?

You need to check everything. At this level of engine work there are no shortcuts and nothing should be left to chance.
 
#6 ·
Edit: disregard, it's just a false picture on that website.

Now one thing I found that's interesting is on a Mopar parts supplier they show a completely different kind of seal. But all the rockauto seals and the seal that I originally had use the type shown in the first post.
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^this is the one mopar shows
 
#10 ·
392 cam, Mopar Performance springs, Manley pushrods. Just from wiggling the valve stem on the top side I can't feel any play so I don't really think guides are the issue either.
 
#12 ·
Right that's what I thought, ik the pre eagles did because I did those on my brother's 05. Now on the seals it's all 4 on one head on the exhaust side. Could it be the lift is too high and catches the seal somehow on this one side? Maybe pushrods are out of spec? I don't have anything accurate enough to measure them unfortunately.
 
#14 ·
I know it is a different engine in this thread but the 2.2 guys apparently use hemi valve stem seals.

And apparently there is yet another style of hemi seal
 
#15 ·
Just by looking at the seals they really don't tell any stories. Only thing that's different from the one that was just on it and a new one is that the new ones hole for the valve stem is slightly smaller but that's probably just how it wears out to fit on the valve.
 
#17 ·
One of these is new and the other is a "newish" used one
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#18 ·
#21 ·
Could be, but the fel pro ones I had prior were also slightly less pronounced and they popped up as well.

And yea that I definitely don't want the scratch on the valve stem either, I'll try to measure it up and see where it ends up. If it does in fact reach it then im just gonna replace all 4 valves and maybe guides while I'm at it just in case. I just don't think they are being hit from too much lift simply cuz they aren't all banged up like I've seen on other cars. Thanks for the ideas
 
#20 ·
Looking at your old and new valve stem, I don't see any impact marks on the top of your old valve stem. How are you installing the valve stems? Aren't they supposed to be tapped in place with a socket or something...or do they just snap in place? The FSM shows no info how to install.


This guy removes it with a special tool but does not show how he installs it.
 
#22 ·
I usually just start by hand and the use a 12mm socket and just pushed that down with my hands. It worked fine on the rest of them and I tried tapping the socket but it didn't make any difference. I do remember the original seals being VERY difficult coming off and that's where some of the valve stem scratches came from tho most are very high up near the keeper grooves
 
#23 ·
You haven't mentioned a sleeve.
Ones I've done came with a cheap piece of a straw, but the job was to guide the seal over where the locks go - so the seal would stretch a bit and be guided over the lock 'cuts' (scratches too?).
But I did buy a gasket set(s), so maybe they assume you have it if you just buy seals?
 
#24 ·
That's interesting never heard of that being used before but it makes sense.
 
#25 ·
I don't think it's that big of a deal, but should the seals go on dry or oil on the guide? I'm just trying to think of anything at this point before I pull the head and send it to a machine shop for new guides. There's nothing that bothers me more than seeing blue smoke.
 
#26 ·
Should these seals be able to come off by hand? After I put them on I can pull them back off with my hands. They're not loose but if I pull hard enough they do pop right off.
 
#28 ·
Yea it definitely takes some force but it's WAY easier than I remember from the original seals. I might just sell this head and buy a new one so I can eliminate any possible issues with valves or guides.
 
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#29 ·
Still stumped over this one. Replaced seals again just so I could see if they popped off while cranking the engine with the valve cover off and nothing happened. But after driving for about 5 minutes it already started smoking again. Not sure what I should do because I can't see any evidence that anything is touching the seal and it doesn't make sense that those 4 guides would just go bad at the same time I installed the cam.
Anyone know what I could expect a shop to charge to pull the head off? Don't feel like doing it myself again
 
#30 ·
Still stumped over this one. Replaced seals again just so I could see if they popped off while cranking the engine with the valve cover off and nothing happened. But after driving for about 5 minutes it already started smoking again. Not sure what I should do because I can't see any evidence that anything is touching the seal and it doesn't make sense that those 4 guides would just go bad at the same time I installed the cam.
Anyone know what I could expect a shop to charge to pull the head off? Don't feel like doing it myself again
I got the same problem. Ordered enginetech seals from rockauto. After driving a day moust of them popped off. So I ordered and installed fell pro once. Now a day letter I see smoke on startups. So its neither rockauto has wrong size data or just crappy seals. I removed enginetech once easy with my fingers, originals was hard to remove. How did you fix a problem? I hate to do it again.
 
#31 ·
I got the same problem. Ordered enginetech seals from rockauto. After driving a day moust of them popped off. So I ordered and installed fell pro once. Now a day letter I see smoke on startups. So its neither rockauto has wrong size data or just crappy seals. I removed enginetech once easy with my fingers, originals was hard to remove. How did you fix a problem? I hate to do it again.
Haha yea it's the engine tech seals. I ended up switching to oem and no issues in 5 months. Fel pros stayed on for basically all my valves except the 4 exhaust valves for some reason, they're still on all my valves except those 4 that are running oem.
 
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#33 ·
Hemi tools spring compressor
 
#35 ·
My brother bought it 2 years ago and I'm glad he did because we've used it 5 times since, when we thought that would be the only time. I think it's like $150
 
#37 ·
Snap-on has it for $148 which is the one I used to replace my springs with heads still on engine. Although the design makes it a little tricky to get the the far back cylinders by the firewall.

Crane cam makes a tool for $100 which seems to give more access to the keepers.
 
#38 ·
Hello guys, I had a #8 misfire and black plugs on #2 happening only when boosting a few times consecutively playing.
I suspected (hoped) its a seal and read posts here on them and am visiting here to share mine.

It recorded #8 because @high RPM it can get it wrong. The misfires were always logged at high revs.

Long story short Felpro told me after asking for a code on the parts card 190919 (decoded = 9/19/2019) they had a bulletin for the date having larger than spec seal mount ID. Well WTF! I guess it was not as important as the Tylenol recall.

They sent me a new set from this year. How about some pain and suffering and labor compensation eh?

I pulled the valve cover today and found the below. The car did not smoke not even boosting, did not use oil unless ran hard but even @WOT no smoke seen by my dash cam or in the lights back there at night.

One of the plugs and the #2 intake seal as found today. I'm changing them all.

I got these misfires randomly never fouling or rough running but always after a couple WOT series but not every time. Then finally I had a good play time with some competition doing several WOT blasts and the engine missed after letting off and I guess burnt it off enough in a minute or two. But it made things more urgent.

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#39 ·
What are the odds of that. I spent in total probably 30 hours labor myself trying to figure it out before switching to oem seals.
 
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