Valve stem seals
Thread Starter
|
Senior User
Joined: Aug 2000
Posts: 407
Likes: 0
Valve stem seals
While replacing valve cover gaskets on my '85 460 I thought I would also do the valve stem seals. My local auto parts store only has a hard plastic type seal which appears to be the type on the motor now. Most seals that I have installed on other motors have been a soft pliable rubber not hard plastic.
I can see where the current seals tend to ride up on the valve stem since they do not get seated and it seems to me that this would allow oil to get below the seal, get drawn down the valve stem, and thus negate the purpose of the seal. Is this a problem on these motors? Is there a better seal to use?
Thanks,
Mark
I can see where the current seals tend to ride up on the valve stem since they do not get seated and it seems to me that this would allow oil to get below the seal, get drawn down the valve stem, and thus negate the purpose of the seal. Is this a problem on these motors? Is there a better seal to use?
Thanks,
Mark
Moderator
Joined: Jan 2001
Posts: 56,949
Likes: 2,718
From: Virginia
Valve stem seals
I have heard of a positive locking type seal, but it requires machine work on the heads to give the proper dimension for it to lock on. I believe most of the oil under the valve cover is flowing down hill toward the drain holes, so if the seal deflects the oil away from the stem area, it's probably good enough to keep the oil consumption down. I guess that's why they call them "umbrella seals".
Senior User
Joined: May 2002
Posts: 298
Likes: 0
From: Denver
Valve stem seals
Positive control is the way to go. I did them on mine, but I also was reworking the heads at the same time. You do have to take off metal for the seal to fit. But once it is done once no need to do it again.
Robert
72 Ranger XLT W/ 86 5.0L W AOD
krazdndenver(No Email Addresses In Posts!)
www.geocities.com/krazdndenver
Robert
72 Ranger XLT W/ 86 5.0L W AOD
krazdndenver(No Email Addresses In Posts!)
www.geocities.com/krazdndenver
Freshman User
Joined: Sep 2001
Posts: 45
Likes: 0
Valve stem seals
Actually the plastic type are very good, in fact the positive type seals are more nad more being made of a high tech plastic vs teflon. Positive type seals are great but require having the heads machined and new guides installed (if you want to do it right). I would go with the new red plastic umbrella type if it was a daily driver or grocery getter to keep the costs down.........
Senior User
Joined: Jun 2002
Posts: 193
Likes: 0
From: Western Slope, Colorado
Valve stem seals
When I had my heads done I did not specify valve stem seals, when I stopped by the shop I noticed that the machinist installed positive type seals on the intake valve stems and umbrella seals on the exhaust valve stems. This seemed to make sense as oil control is more of a problem on the intake side and this saved me cost on the exhaust side. Time will tell.
Wes
Wes
Thread
Thread Starter
Forum
Replies
Last Post
DarylZ
Pre-Power Stroke Diesel (7.3L IDI & 6.9L)
3
Oct 22, 2004 03:20 PM
David10
335 Series- 5.8/351M, 6.6/400, 351 Cleveland
2
Jul 5, 2003 11:08 PM
ADSf100
FE & FT Big Block V8 (332, 352, 360, 390, 406, 410, 427, 428)
2
Apr 8, 2003 07:53 AM
Mr Personality
Big Block V8 - 385 Series (6.1/370, 7.0/429, 7.5/460)
3
Dec 4, 2002 11:52 PM
