valve seal replacement (best choice)

[WZ JUNK]

The engine in my Chevy has some bad valve seals and I need to replace them.  It was not started for a least 10 years during the storage and build of the car.  Now it puffs a little smoke once in a great while, usually when I am leaving a cruise night or car show.  I need some feedback on the best seals to use.  This is the 1990 5 liter TBI roller motor (305).  I only want to do this job one time.

John

[58 Yeoman]

Way back in the late 70's or early 80's, I had a 72 Monte Carlo with a 454. I drove it to Baltimore, MD and back and used 13 quarts of oil. It didn't smoke that I could see. My cousin suggested that I install Perfect Circle valve stem seals. It cured the problem.

[Arnold]

If it does it now and again..most likely muck in there. Get something in there..check breathing. Could be a valve moving around on the guide in there..maybe some muck in there. Some solvent type cleaners may re-juvenate the seals,,get the muck out. P.C seals as mentioned are good. However..if there is valve stem movement..they won't last forever..and at some point..some guide/stem work.

[Bruce Dorsi]

There's quite a selection to choose from:

http://www.rockauto.com/en/catalog/chevrolet,1990,k1500+pickup,5.0l+305cid+v8,1050837,engine,valve+stem+seal,5800

I prefer positive-type seals, which are tight on the valve guide, and "wipe" the valve stems.  .....Some do not require machining the o.d. of the guides.

Solid Teflon seals are not good for street motors, as they will deform in lose their sealing ability.

Umbrella-type seals can actually act as oil pumps, and force oil down the guides, if a SBC is installed at a steep angle (rear down).

[Arnold]

Way back in the late 70's or early 80's, I had a 72 Monte Carlo with a 454. I drove it to Baltimore, MD and back and used 13 quarts of oil. It didn't smoke that I could see. My cousin suggested that I install Perfect Circle valve stem seals. It cured the problem.

  Had terrible oil burners that did not smoke..or even leave much residue in the tail pipe. 1 Volvo. ZERO smoke..1 quart every 40 miles. My late fathers 1973 Comet/Maverick..6-250. zero compression on 1 cyl. He told me to fill the oil...(it was full)put some extra in it..take lots. I did none of the above :oops: I mean I KNEW..it did not smoke either. Oil light came on after 80 miles.
I had to drive it with the oil light on till we found some more oil
 I parked an LS3 engine p/u in an old wood frame gravel floor garage to store it over the winter. Come spring it was seized solid. Finally got it going..smoked now and again..finally took out a stem/guide.
 Sometimes you can get an intermittent smoker by a valve rotating/not rotating properly(sometimes rotators) and the valve stem cocking in the guide,or the valve getting hung up on muck on the seat.
 Really overheating something can bake the seals too.