Valve stem seals?

Discussion in 'Technical' started by NewMaverickGuy, Mar 3, 2018.

  1. NewMaverickGuy

    NewMaverickGuy Member

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    It looks like this 200 I have crapped the valve stem seals. How would I replace them? And what would happen if I ran it with them blown out?
     
  2. dyent

    dyent Member

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    Worn, cracked or damaged valve stem seals would allow oil into the cylinders which would burn, belch out blue smoke and foul your plugs, depending on condition of valve guides, could be a little smoke or alot too! Do you know how many miles on the engine? has it been rebuilt? Something that should be looked at........
    David
     
  3. Krazy Comet

    Krazy Comet Tom

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    After around 75-80K miles all the engines of the '60s & '70s had bad valve stem seals(even some of the '80s & '90s)... If bad enough, oil consumption will increase to as much as quart per 200 mi.. Was common on 289 & 302 for the pieces of seals to find their way into oil pan, there they were sucked into pump, locking it solid... Dunno enough about 6cyl to know if those suffered same fate...
     
  4. NewMaverickGuy

    NewMaverickGuy Member

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    I found pieces of seal under the valve cover. The engine is original to the car, with about 76k on it. They were pretty big pieces, with some of it chewed up. The pieces of seal were rock hard like bakelite.
     
  5. NewMaverickGuy

    NewMaverickGuy Member

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    I really would like to rebuild the head. I'd like to do it myself. I don't know enough about this engine or what special tools I need to do it though. I would actually like to rebuild the whole engine.
     
  6. Krazy Comet

    Krazy Comet Tom

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    Most sets of seals I've replaced were with head installed... Usually 289/302 & 2.3 OHV 4cyl, all fairly easy... Compressed air, the spark plug adapter and tool are all that's needed... Same will apply to a 6cyl but I dunno how difficult it will be to source the tool, generally are mfgr'd for a specific engine family... Tools aren't much more than a specialized pry bar, with shaft type rockers, usually requires removing rockers from shaft and reinstalling the stripped assembly...

    Note, don't ever attempt a 4.6 mod motor, those are a bitch... I did one side and oil consumption went from 500mi to almost 1500, said that's good enough... Luckily Ford realized their screw up and used quality seals after the first four years... Was common to see Crown Vic belch smoke when pulling away from a stop...
     
  7. NewMaverickGuy

    NewMaverickGuy Member

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    I ordered the seals. Will any valve spring compressor work or does it have to be a special one?
     
  8. Krazy Comet

    Krazy Comet Tom

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    From my previous reply...

    Same will apply to a 6cyl but I dunno how difficult it will be to source the tool, generally are mfgr'd for a specific engine family... Tools aren't much more than a specialized pry bar, with shaft type rockers, usually requires removing rockers from shaft and reinstalling the stripped assembly...

    Meaning the ones for 2.3 or 302 etc won't work... To use the conventional C clamp type requires head removal...
     
  9. NewMaverickGuy

    NewMaverickGuy Member

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    The only type I have immediate access to is this. spin_prod_1163354612.jpg
     
  10. Craig Selvey

    Craig Selvey Indiana State Rep - MCCI Supporting Member

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    I am somewhat experienced on working on engines. I have had the exact same problem that you described at least twice with a 6 cyl motor. Pretty sure I did a write-up about it on this message board. If I can go find it, I will add a link to it.

    Noting what you have said above, do what I did. Pull the head off yourself, and take it to a machine shop and have the work done.
     
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  11. Craig Selvey

    Craig Selvey Indiana State Rep - MCCI Supporting Member

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  12. groberts101

    groberts101 Member Supporting Member

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    I agree with Craig. Costs more cash to sub out work but the reduction in migranes is well worth it.. if you catch my drift here.

    Plus there's very little you can do to that head yourself unless you start buying expensive tools and getting more serious about engine building to the point the tools would pay for themselves.

    PS.. make sure to do a resurfacing cleanup cut on that head while the machine shop has it. Longer cylinder heads tend to move around more over time and the flatter the better for the head gasket. Also can use a lever type compressor like this on these heads since the valve springs are such low pressure. Can still use it on higher spring pressures too but will need a hell of a cheater bar attached to the handle. lol

    https://www.ebay.com/i/321631518401?chn=ps
     
  13. mojo

    mojo "Everett"- Senior Citizen Supporting Member

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    I agree w/ the suggestions, "Take the head to machine shop"! That head may need more than what you believe or what may be obvious to the naked eye. Otherwise, you may end-up having to do the job more than once. JMO!
     
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  14. NewMaverickGuy

    NewMaverickGuy Member

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    I think I'm going to just do the valve stem seals guys. Not to say I don't know anything about engines or this engine in particular. (I figure out this kind of stuff really quick. hell, I taught myself how to read at 5 years old)
    The engine doesn't have any issues right now that would warrant me taking any major part of the engine off. I'm just a perfectionist when it comes to stuff like this and it bothers me that there's probably things inside of it that aren't "up to spec" or something.
     
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  15. Krazy Comet

    Krazy Comet Tom

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    Agreed...

    Assuming good compression, I've never done anything more than replacing stem seals, and that was with head in place... Never a issue in the time I ran the engines... Note this was mostly in a era that valve stem seals were failing within 65 to 75K miles... Head/valves was generally OK for another 50K or more....

    I'd check compression before making a firm decision... Having four cylinders at 125 psi, one at 100 & another at 80 will probably never be detected in operation... BUT, likely there's trouble a brewin'... It is fairly common for these engines to have cracked valve seats, no effect on oil consumption but will knock down compression...
     

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