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Old 06-26-2012, 11:18 AM   #26
rs72z
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Re: Foul plugs and oil leak I cant trace

Like has been said sevral times check the intake. If it's not sealed good on the bottom it will suck quite a bit of oil into the cylinders. Then after it sits the oil will start seeping around the threads. Pull the intake and look in the ports if it's leaking there will be oil in the ports. Leaking vacuum will also cause it to run rough.
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Old 06-26-2012, 12:05 PM   #27
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Re: Foul plugs and oil leak I cant trace

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Like has been said sevral times check the intake. If it's not sealed good on the bottom it will suck quite a bit of oil into the cylinders. Then after it sits the oil will start seeping around the threads. Pull the intake and look in the ports if it's leaking there will be oil in the ports. Leaking vacuum will also cause it to run rough.
yes...thats probably my last resort. It could well be it, because the two plugs are fouling from the top. so it may be oil coming in from the intake valve?

I got another question.

how can I check if the fluid on the outside of my engine is oil or coolant? since there isnt any oil in the heads on the outside, where the engine is wet...
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Old 06-26-2012, 01:32 PM   #28
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Re: Foul plugs and oil leak I cant trace

Looks to me like it's seaping from the valve covers at the rear corners. What type of gaskets did they use on the valve covers? Cork? It's best to get some felpro rubber gaskets and make sure the sealing rails on the valve covers are flat and true.
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Old 06-26-2012, 01:53 PM   #29
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Re: Foul plugs and oil leak I cant trace

Again, check the valve covers. You haven't said you tightened them or checked the gaskets.

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Old 06-26-2012, 02:09 PM   #30
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Re: Foul plugs and oil leak I cant trace

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Again, check the valve covers. You haven't said you tightened them or checked the gaskets.

riz
ok, some help maybe. how do you check the gasket of a valve cover?

do you just take the valve cover of? and look for ...?

but like I said..I have run my hands all around the heads with warm and cold engine and dont come up with any oil leaks...so..........I kinda hesitant to open up something that seems fine...any tips?
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Old 06-26-2012, 02:40 PM   #31
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Re: Foul plugs and oil leak I cant trace

we checked the engine today and the whole engine seems to be dry above the spark plugs. We cant find a leak.

the oil on the spark plugs is from inside the engine cilinder, because its only on the sparkplug up to the tapered part and not beyond. so its from inside.

the oil on the outside of the engine is probably coming fro a remote leak somewhere and flowing along the edges. need to look into that.

we have now tried one degree hotter plug in the nr5 cilinder, where the fouling is the worst, to see if this fixes the fouling and burn the oil.

I'll check the plug in a couple of days.
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Old 06-26-2012, 02:59 PM   #32
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Re: Foul plugs and oil leak I cant trace

Put a socket on the 4 studs on each valve cover and check to see if they are snug. you don't want to over tighten them or it will warp the gasket.
Also would feel the around the front and back of the intake. It can leak at the ends where the head and intake meet, then run down the edges of the heads to the block surface.

I still think you need to pull the intake, i bet it's leaking inside.
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Old 06-28-2012, 03:11 PM   #33
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Re: Foul plugs and oil leak I cant trace

tested a hotter plug for two days...was hoping it would fix the fouling.

here's the result after two day

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Old 06-28-2012, 03:19 PM   #34
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Re: Foul plugs and oil leak I cant trace

The hotter plug might stop your fouling for a while but it's just hiding a bigger problem that still needs to be adressed.
How much oil is it using?
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Old 06-28-2012, 03:20 PM   #35
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Re: Foul plugs and oil leak I cant trace

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The hotter plug might stop your fouling for a while but it's just hiding a bigger problem that still needs to be adressed.
How much oil is it using?
I need to check on a flat service tomorrow...will check...
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Old 06-29-2012, 03:16 AM   #36
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Re: Foul plugs and oil leak I cant trace

cylinder head porting The bottom of the stud isn't really entering into port. When porting, a person will 'break through' exposing the bottom of the(otherwise blind) threaded hole the stud is screwed into."

When porting, I didn't go any deeper than 2'' into the ports
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Old 06-29-2012, 07:46 AM   #37
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Re: Foul plugs and oil leak I cant trace

I thought about this also but, the heads had press in studs unless they were modified for screw in. Right?
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Old 06-29-2012, 09:13 AM   #38
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Re: Foul plugs and oil leak I cant trace

Have you retorqued the intake yet?
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Old 06-29-2012, 10:19 AM   #39
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Re: Foul plugs and oil leak I cant trace

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Have you retorqued the intake yet?
shop said it is a non-re-torqueable gasket, so they didnt want to re-torque it.

disconnected the PCV this afternoon, put a bolt in the hose and took it for a 1 mile highway drive.

I was hoping the PCV was sucking in too much oil into the intake manifold, because it looks wet from oil when I take it out.

brand new plug turned up like this:

top


bottom:



again black on top, clean on the bottom and oil on the threads till the tapered end.
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Old 06-29-2012, 10:35 AM   #40
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Re: Foul plugs and oil leak I cant trace

If they wont check the bolts it might be time for a new shop.

Just put a wrench on all of them and see if they are tight. Start in the middle and work your way out. I have seen intakes that i put on get loose many times, it's just from the gasket shrinking some with heat cycles.

Does the heads have screw in rocker studs?
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Old 06-29-2012, 10:42 AM   #41
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Re: Foul plugs and oil leak I cant trace

I agree with rs72z, if they don't want to take 5 minutes and check the torque, go somewhere else.
I would still remove and check the intake. Maybe the gasket isn't seated properly. Or a couple of bolts aren't tight.
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Old 06-29-2012, 11:34 AM   #42
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Re: Foul plugs and oil leak I cant trace

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If they wont check the bolts it might be time for a new shop.

Just put a wrench on all of them and see if they are tight. Start in the middle and work your way out. I have seen intakes that i put on get loose many times, it's just from the gasket shrinking some with heat cycles.

Does the heads have screw in rocker studs?

I think I have a torque wrench. I'll see 2nite if I can use to retorque the heads? or intake manifold?

and this is a picture of my rockers...dont know if they are screw in type? how can you see?

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Old 06-29-2012, 12:01 PM   #43
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Re: Foul plugs and oil leak I cant trace

Those are press in rocker studs.

If you are certain the heads aren't the cause, and the PCV has been eliminated as a culprit, then it's probably sucking oil thorugh the valley (under the intake).

Short block have alot of miles on it? And why is there a gloppy mess of oil laying on the intake under the carb? That's where an intake bolt would be. Looks like who ever installed the intake didn't put thread sealant on the threads and it's pushing oil through the bolts.....Very common mistake. That would be enough to make me want to pull the intake and check the gasket seal and clean things up. And just so you don't have to do it again, I'd check the bottom of the intake for flatness to be absolutely sure it will clamp evenly for a good seal. I've had those old cast iron intakes warped before.
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Old 06-29-2012, 12:13 PM   #44
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Re: Foul plugs and oil leak I cant trace

I am guessing that pic is pre repairs..... i hope

As far as retorque goes, it's the intake we are talking about. Don't worry about using a torque wrench just use a boxed end wrench and snug each bolt and then let us know how far if any they moved.

Check the bolts first before you go any farther.
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Old 06-29-2012, 01:41 PM   #45
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Re: Foul plugs and oil leak I cant trace

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I am guessing that pic is pre repairs..... i hope

As far as retorque goes, it's the intake we are talking about. Don't worry about using a torque wrench just use a boxed end wrench and snug each bolt and then let us know how far if any they moved.

Check the bolts first before you go any farther.
its pre reair yes :-)

hahahaha....OK, I'll check later 2nite using just a simple boxed wrench.
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Old 06-29-2012, 03:14 PM   #46
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Re: Foul plugs and oil leak I cant trace

checked 2nite and used a boxed wrench.

result:
the bolts with the red circle felt pretty loose and could easily be fastened a little more and are not even snug right now to my opinion. The other I couldnt move with my small boxed wrench

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Old 06-29-2012, 03:17 PM   #47
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Re: Foul plugs and oil leak I cant trace

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checked 2nite and used a boxed wrench.

result:
the bolts with the red circle felt pretty loose and could easily be fastened a little more and are not even snug right now to my opinion. The other I couldnt move with my small boxed wrench

What plugs were getting wet?
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Old 06-29-2012, 03:18 PM   #48
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Re: Foul plugs and oil leak I cant trace

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What plugs were getting wet?
cylinders 1 and 5
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Old 06-29-2012, 03:20 PM   #49
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Re: Foul plugs and oil leak I cant trace

Hows it running with good plugs in?
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Old 06-29-2012, 03:21 PM   #50
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Re: Foul plugs and oil leak I cant trace

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Hows it running with good plugs in?
it runs super with fresh clean plugs...good response, easy idle, etc...

just gets black on top quickly
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