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Old 06-29-2012, 03:23 PM   #51
rs72z
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Re: Foul plugs and oil leak I cant trace

Hopefully this will help, wait and see. Goodluck.
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Old 07-04-2012, 11:38 AM   #52
kikkegek
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Re: Foul plugs and oil leak I cant trace

somebody pointed me to a nice video. Its show how the fuel flows over the spark plug from one side...thus when taking along oil from an kinda leak from above the valve, fouling it while taking in fuel.

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Old 07-04-2012, 03:31 PM   #53
Desert1957
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Re: Foul plugs and oil leak I cant trace

Here is my best guess...

You said the Heads were "Replaced" or "Re-Done" , that term is used a lot and can mean anything.

Were the valve guides re-done? and not just knurled? What valve seals were installed? If you had "Teflon" seals installed , all of the bosses on the heads must be machined. Big$$$$ This is a very expensive machine shop procedure. I have heard many shop quotes that often exceed the price of a new pair of heads and will try and discourage people from spending that much on an old pair of stock heads.

Re-doing a cylinder-head the correct way is a multi-step process that gets very pricey.

If you paid less than $500 , you probably got the quick y repair. Which doesn't guarantee no oil consumption.

Did they machine the Heads? If so they may have taken too much material off , which can lead to sealing problems at the intake gasket area. The head can be low enough where its sucking crankcase air at the lower edge.

If the heads were machined, the intake now does not match like it use too and may need to be machined at the mating surface. which can cause gasket sealing problems.

You never mentioned anything about the Short Block itself, How many miles? Is it the Original engine? What did the tops of the pistons look like with the heads off? Were the clean or crusty build up on top?

I ask these questions because it still could be a cracked top oil control ring which doesn't effect compression. Engine can run great with good power but still foul plugs quickly and have issues trying to push the extra un- burned oil out.

Last edited by Desert1957; 07-05-2012 at 08:19 AM.
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Old 07-04-2012, 03:39 PM   #54
Desert1957
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Re: Foul plugs and oil leak I cant trace

After looking at the pictures again, this is WAY too much oil for an intake leak. This looks like the cylinder is being overrun with oil. I thinking rings at this point. If it was a valve guide seepage problem only the side facing the intake valve would be crusty, Your plug is completely covered which means the oil is filling the whole cylinder.

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Old 07-04-2012, 05:08 PM   #55
kikkegek
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Re: Foul plugs and oil leak I cant trace

Quote:
Originally Posted by Desert1957 View Post
Here is my best guess...

You said the Heads were "Replaced" or "Re-Done" , that term is used a lot and can mean anything.

Were the valve guides re-done? and not just knurled? What valve seals were installed? If you had "Teflon" seals installed , all of the bosses on the heads must be machined. Big$$$$ This is a very expensive machine shop procedure. I have heard many shop quotes that often exceed the price of a new pair of heads and will try and discourage people from spending that much on an old pair of stock heads.

Re-doing a cylinder-head the correct way is a multi-step process that gets very pricey.

If you paid less than $500 , you probably got the quick y repair. Which doesn't guarantee no oil consumption.

Did they machine the Heads? If so they may have taken too much material off , which can lead to sealing problems at the intake gasket area. The head can be low enough where its sucking crankcase air a the lower edge.

If the heads were machined, the intake now does not match like it use too and may need to be machined at the mating surface. which can cause gasket sealing problems.

You never mentioned anything about the Short Block itself, How many miles? Is it the Original engine? What did the tops of the pistons look like with the heads off? Were the clean or crusty build up on top?

I ask these questions because it still could be a cracked top oil control ring which doesn't effect compression. Engine can run great with good power but still foul plugs quickly and have issues trying to push the extra un- burned oil out.
I paid €1600,- for the whole job:
heads were completely redone,
new stem valve seals teflon
new bronze guides
new hydraulic lifters
heads were flattened (machined)

dont know all other details...

I didnt see the cilinders and pistons, but they told me the walls were smooth, no sign of bad rings or excessive wear, so no need to do a full engine rebuild...that is why I have a hard time right now to accept that they say its probably my rings now...

I have noticed that along the intakegasket its a little wet and in some places there is a small puddle of very thick oil...I need to clean that of and see how quick it build up again...

I am planning on pulling the intake off when I get back from summer holiday..southern france...600 mie drive back and forth with the suburban...

I'll report back here of course
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Old 07-04-2012, 07:38 PM   #56
tucsonjwt
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Re: Foul plugs and oil leak I cant trace

Everything I know about engines you can put in a thimble and have a lot of room left over, but every engine I ever had with that amount of oil/crud on the plugs had bad rings.
I no longer believe in rebuilt engines. I think once you crack a factory engine open and start fiddling around with it you never get it back together as well as the factory did. All rebuilt engines I have had were not very good. The only exception is my current 83 with a Goodwrench rebuilt 454, but my experience with 454s is that they run smooth if properly tuned even if they have some slop in the engine.
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