Replacing Valve stem seals which are which?

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Dusted27

Dusted27

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Hey Guys, I am replacing valve stem seals on my Duster with a 360ci. My problem is i have two different sizes and am not sure which are the Intake and which are the exhaust! Ones a bigger seal then the other. I should not have this problem because i would replace the seal with the size that is on it. My problem is some jack hole pulled them all apart then left them that way. so here i am putting my heads back together and dont know which size seal goes to which set of valve stems. You would not believe how hard it is to find this answer! any thoughts? Thanks in advance
 
Intake right, exhaust left.

1mnu.jpg
 
And the why of it will help you remember for next time.
Since on the intake stroke, the pistons are putting the suck on the system, they like to suck oil past the intake valve stems. This causes smoking out the tailpipe as the oil burns in the chambers, but worse is that the oil in the chamber likes to contribute to detonation, and don't forget; that burning oil is pollution. To prevent this,the intake guides need to be well-sealed.
Now on the exhaust side; These valves are not usually under vacuum, so a little oil in the guides leads to a longer guide life. So the umbrella seals divert the bulk of the oil, but let a little sneak by.
There, if you read this, you will likely remember it.
 
AJ/FormS said:
And the why of it will help you remember for next time.
Since on the intake stroke, the pistons are putting the suck on the system, they like to suck oil past the intake valve stems. This causes smoking out the tailpipe as the oil burns in the chambers, but worse is that the oil in the chamber likes to contribute to detonation, and don't forget; that burning oil is pollution. To prevent this,the intake guides need to be well-sealed.
Now on the exhaust side; These valves are not usually under vacuum, so a little oil in the guides leads to a longer guide life. So the umbrella seals divert the bulk of the oil, but let a little sneak by.
There, if you read this, you will likely remember it.
Click to expand...

Good info AJ
 
I was told that those Fel-Pro intake seals are designed to be pushed down onto the valve guide where they are suppose to stay. They have ribs on the inside that helps them to lock to the valve guide. The Fel-Pro exhaust seals ride up and down with the valve steams in the same manor that the factory umbrella intake and exhaust seals did.
 
694spd said:
I was told that those Fel-Pro intake seals are designed to be pushed down onto the valve guide where they are suppose to stay. They have ribs on the inside that helps them to lock to the valve guide. The Fel-Pro exhaust seals ride up and down with the valve steams in the same manor that the factory umbrella intake and exhaust seals did.
Click to expand...
I just recently replaced the valve stem seals on the 225 Chrysler Industrial gas slant 6 engine on my 1975 Lull 400 rough terrain forklift, discussed elsewhere in this forum, and posed the question as to whether these seals (particularly the intakes) are supposed to move with the valves or stay put. AJ/FormS gave helpful advice, but with this post, there appears to be conflicting information. So which is it?
 
Just like sireland67 mentioned earlier. The ones in the package on the right go on the intake valves and slip down and lock on the guide boss. The other pack on the left go on the exhaust valve and are just umbrella seals that ride up and down with the valve.
 
For /6 and V8 Felpro PN's:
Intake is SS70537 (old VS4405)... umbrellas
Exhaust is SS12764 (old VS4404)... flatter seals
 
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