Fel Pro valve stem seals?
#1
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Hey what’s up guys, i just finished a head rebuild on my 1.6. (Shaved, mild valve job, valve seals). I got the car running about a week ago and got some smoke at startup and decided to do the valve seals again because that was the most likely issue. So i did, and the smoking went away, for about a week. Two days ago, i noticed some smoking at stop lights, and at cold start. Both sets of valve seals were felpro and i gave the first set the benefit of the doubt thinking i screwed something up with the install. However, these ones should be all good. Anyone have experience with these? I’ve read they are ok, but just wondering what you guys think. I’ve already added a pop rivet restrictor to my oil feed, and made sure the drain line is a-ok, just to the rule the turbo out of the equation, which is a freshly rebuilt sr t25. Do i really have to do these damn seals again with OEM?
#4
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If the guides have worn oversize or have become out of round/oval it allows the valve stems to move and the seals lose their effectiveness. Not saying this is your problem but if going through the expense of a valve job checking the mechanical dimensions is a 1st thing as it kind of dictates what you do or if the head is worth doing.
#6
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Yes, i agree. Although it didn’t smoke before, and like i said was fine for about a week. Considering the seals see no actual movement (except if the valves were moving around that much), i don’t think the valve guides are causing this particular issue. Unless, valve play is causing the seals to prematurely sh*t the bed.
#13
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@Savington Please comment on valve guide knurling vs replacement.
#15
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Much of the cost is in the install, since you typically have to recut the seats once the new guides are installed and reamed to size. IOW, it effectively requires a full head R&R. We use SI's manganese bronze guide and have had no issues with them.
#16
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Yeah, i think i’ll try the oem ones. If they work they work, id do the guides myself, but still just a little labor intensive for what my goal is with this motor at least. As far as knurling, i’d still have the pull the head and then send it off to get them knurled. So at that point i think anyone would be better off just replacing the guides.
#18
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They seem to be very similar to oem quality, according to the test done by Mudflap in the “which stem seals leak” thread. Although the fact that USED oem seals holds quite a bit of weight when compared to the other ones. A question for Savington, in this case, would i want a seal with the tightest fit (ie smallest ID) or one that holds the most weight?