Fouling #6 plug
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Pronto
No amount of evidence will ever persuade an idiot.
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- Dec 9, 2002
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- 16,806
Weak or broken valve spring?
Just figured I would update this to let you know what was found. With valve covers off and a straight edge, 5 of the 6 intake valves were sitting low. Removal of engine showed drivers motor mount broke in 2 places (I have owned car since 107k miles and a torque strap was the 2nd thing I ever did to the car) passenger mount was sagging, which was causing the 3.5" THDP to rub/hit the frame. Pulling the lifters showed a concave exhaust #2, pulling the cam showed the lobe on exhaust #2 was more than 1/2 gone (Been using ZDDP additive since I first read about it from Kirban) and the rest were showing wear. Pulling the heads showed the reason #6 was fouling, the #6 intake valve guide/seal were shot, would drip/seep oil just sitting there! All in all I'm very surprised the car ran as good as it did, I'd say less than 1k miles ago is when it ran the 11.55@118, it still idled well. My good friend doing the work said he only drained 4.5 quarts of oil, it was changed around 500 miles ago, so I'm thinking most of it got burned through #6, but it didn't smoke except above 22psi. Can't wait to see how she runs with the new heads & cam!!
Damn. I hate that I guessed that one correctly 
Since it was an exhaust guide you wouldn't have seen the smoking as much. Since that port is pressurized the oil gets blown upwards and pretty much vaporized. After that it's left to the PCV and vents to take care of it. When you get the heads apart you'll probably notice the valve stem is blackened with vertical lines on it.
On the upside, your tired combo can run mid 11's on 5 holes. Just think of how it's going to act with all 6 pulling!
Was this a virgin cam and lifters from the 80's or had they been changed in the past?
Since it was an exhaust guide you wouldn't have seen the smoking as much. Since that port is pressurized the oil gets blown upwards and pretty much vaporized. After that it's left to the PCV and vents to take care of it. When you get the heads apart you'll probably notice the valve stem is blackened with vertical lines on it.
On the upside, your tired combo can run mid 11's on 5 holes. Just think of how it's going to act with all 6 pulling!
Was this a virgin cam and lifters from the 80's or had they been changed in the past?
Damn. That's pretty wild. Usually it's not the 80's parts that fail like that. I almost wonder if what the say out 'over additiving' with ZDDP is true.
I guess it's a good thing the valve guide made you start looking before it got catastrophic.
I guess it's a good thing the valve guide made you start looking before it got catastrophic.
It really is! All things considered I'd say the engine held up pretty well for all the torture I put it through over the years trying to get it quicker than an 11.49 at such high elevation
Pronto
No amount of evidence will ever persuade an idiot.
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Glad you found the issue. So even if it wasn't fouling the plug and valve seals leaking you still had other major issues. Either way you were in for some repairs. Hope you build goes well.
Pronto
No amount of evidence will ever persuade an idiot.
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- 16,806
Did the balancer hurt the snout? It would have been nasty if that let go.
6gunn
high on gas fumes
- Joined
- Sep 21, 2003
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- 555
Wow, interesting pics! That keyway on the balancer looks boogered up. Did that throw off the timing or is it suppose to be like that?
T- Type Tim
Vice Chairman
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So.... Would replacing the valve seals only fix the oil problem?
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