Spark plug valve cover seals... installation woes

[TridenT]

So, there are replaceable seals that seal off the oil within the valve cover from the spark plug tube that contains the spark plug. Sounds nice. Of course, I forgot after I took all my spark plug valve cover seals off which way to install these seals. (They go on one of two ways)

I installed them, probably, the correct way the first time. However, I noticed when I took off my valve cover (I was replacing a valve cover bolt that broke) that my seals were all pretty much ruined. They all got sliced to shit by the spark plug tubes. (Sharp fuckers, apparently) And I thought, "Well, I probably installed them the wrong direction..." So I bought a new valve cover gasket set ($15. Both sets I've used so far are Felpro). Installed them the other way. Aligned the holes as best as I could with the valve cover... No go, Joe. It sliced the shit out of those ones too.

What the fuck do I do? How do I avoid this? It seems UNAVOIDABLE. Does the inner ring of these seals go INSIDE the spark plug tube or outside? (Either way could make sense!)

It's ridiculous. I've gone through two sets. So far I haven't had a misfire (as far as I can tell) with either set. (A symptom I would imagine from having too much oil in your spark plug tube)


The first set didn't have any noticeable amount of oil in the spark plug tube. I'll go check the spark plug tubes later. (I just drove 250+ miles on this new set)

Whatever! I need a good video! It doesn't seem possible to NOT cut the rubber on these. (Made Felpro just fucked up with their measurements)

 

[phucheneh]

Felpro does indeed fuck up. A lot. But you're probably just installing them wrong.

Most likely, it's a shaft seal that you're treating like a gasket. I.e. the whole seal should go AROUND the tube; not be pushed against the end of it.

Pics, or at least mentioning what kind of car you're talking about, would probably be helpful.

 

[tortillasoup]

Exactly, when you install the valve cover on top of the plug tubes, the seals should go completely around the tubes. Don't let the tube cut up the seals at all, gently install it.

 

[Zenmervolt]

So far I haven't had a misfire (as far as I can tell) with either set. (A symptom I would imagine from having too much oil in your spark plug tube)

If the spark plug's seal can keep around 1,000 PSI of combustion pressure inside the cylinder with no leaks (which it does), it's not going to let in oil at basically 0 PSI from the tube to foul the tip and cause a misfire. And if you were losing enough oil through the tubes to short out the electrical connectors on the plugs, you'd be having much bigger problems from low oil before you had a misfire issue.

Also, what usually leaks are the seals between the spark plug tubes and the head. Replacing those requires removing the rocker arm assemblies. Right now, I'm assuming you're only changing the seals at the top of the tube and not the bottom.

Fundamentally though, the important thing is to go slowly, and to make sure you're not forcing anything.

ZV

 

[tortillasoup]

Well what usually happens is that the oil that gets into the spark plug well softens the rubber boots on the ignition wires, eventually failing and allowing the ignition wires to ground out, causing a misfire. Having oil in the spark plug wells isn't the end of the world but is definitely something that should be addressed when possible/convenient.

 

[bruceb]

Also put a drop of oil on each seal before you try to install it. This will make it easier to pass through the gasket or the cover.

 

[Zenmervolt]

Well what usually happens is that the oil that gets into the spark plug well softens the rubber boots on the ignition wires, eventually failing and allowing the ignition wires to ground out, causing a misfire. Having oil in the spark plug wells isn't the end of the world but is definitely something that should be addressed when possible/convenient.

You would need oil in the spark plug tubes to a depth of a couple of inches before it would reach the point on the plug wires where there's anything to ground out. Otherwise all it's doing is softening the boot, which typically extends a couple inches past the point where electrical contact is made.

If he's getting that much oil in the tubes in 250 miles, he'd be noticing a lot of other problems.

Given that he said he didn't see much oil in there at all, his "misfire" theory is pure bunk. It takes a large amount of oil in the spark plug tubes for a long time for things to get to a point where there would be issues from the plug wires grounding out and that's just plain not what he's described.

Bottom line, you were technically correct but also wholly irrelevant to the OP's situation.

ZV

 

[Throckmorton]

Pics??

 

[TridenT]

Sigh. I forgot to take a picture while I was out there.

There is oil in all four spark plug tubes. It is not a lot, but it is there. (Just a few drops spread that are spread out) I will replace the seals this upcoming week. I was thinking of doing it today, but I don't have access to all the tools that I normally do. I don't want to fuck it up and then be royally screwed. I'm thinking of doing it today anyway... I'll check what tools I have here.

 

[njmodi]

Hey TridenT - is this on your Civic? I think so based on your other thread. I just did this job on my Accord and yours should be similar.

I used Felpro gaskets as well. The spark-plug tube seals press into the underside of the valve cover with the flat side facing you, i.e. valve cover upside down, seal presses into the cover, once seated, the flat side should be exposed to you.

I found that the fit is quite tight to get the valve cover back on and it took some coaxing to get each seal spread around the spark plug tube. I oiled the inside of the seal (the surface that mates the spark plug tube) and the spark plug tube itself liberally, but it was still tricky.

I had to work each seal around the tube one at a time gently pushing the seal around the tube.

 

[SpatiallyAware]

Year make model???

 

[lpmart1]

My 94 Corolla with 375,000 miles started blowing oil around the tube top seal. There was only enough oil on the wires to cause miss fires and slow take off. I would clean the wires and the car would run fine for about 50 miles and start miss firing again. The plug wires would again be coated in oil. I put new plug wires on and it ran great even with the oil coating. I know the oil will cut short the life of the plug wires so I am installing spark plug seals tonight. Does not seem like it should be to hard so I will post tomorrow.

 

[Brandyk]

Hi, i know this thread is old but i just need a simple answer.I removed my valve cover on 1992 Toyota 5A/4AF 1600 16 valve.How deep must the spark plug tube seals go in? Must i push them totally in so they are seated right against the top of the cover?


Brandyk... Let let this one die in peace please...

AT Moderator
Bartman39

 

[TridenT]

Hi, i know this thread is old but i just need a simple answer.I removed my valve cover on 1992 Toyota 5A/4AF 1600 16 valve.How deep must the spark plug tube seals go in? Must i push them totally in so they are seated right against the top of the cover?

At least on my car, it was that you had to push them all the way in until they were flush with the cover. I must've damaged a set of seals or two from accidentally putting them in the wrong way. Either way, it's not the easiest job to get correctly because sharp metal loves to chew those seals up.

And then the spark plug cylinders must go inside the seals enough to where no oil is going to get inside the spark plug cylinder. Be careful when aligning the valve cover back on... that's where those cylinders would break apart all your work.