Just pulled the three front bank spark plugs to check their condition, and one of them was quite oily. Covered in a layer of fresh clean engine oil, which I then wiped off. The far passenger side plug. It was also very very tight, I snapped my el cheapo SCA plug removing tool trying to undo it, ended up getting it out using a ratchet & plug socket, but even then I had to give the ratchet handle a fair tap with a steel mallet. First time I have removed these plugs since they were put in back in June last year.
No oil in the plug tube and no oil in or on the connector.
See pics below, the suss plug stands out like the proverbials, it's got a black end compared to the others.
I change my oil every 10,000k and for the last 60,000k or so I've gone through about a litre of top-ups between changes.
The plugs are NGK BKR6EGP platinums.
Seems to me I'm burning oil in that cylinder, and I'm guessing the piston rings in that cylinder are a bit worn.
Thoughts?
Advice?
(and not just you Max!)

http://i990.photobucket.com/albums/af28/kj380/IMG_0388_zps805ca9bd.jpg
http://i990.photobucket.com/albums/af28/kj380/IMG_0387_zps3c3c30b5.jpg
http://i990.photobucket.com/albums/af28/kj380/IMG_0386_zpsc9b82dbf.jpg
http://i990.photobucket.com/albums/af28/kj380/IMG_0385_zps740dff9b.jpg

I gather you mean fresh oil on the outside of the spark plug from leaking tube seals. One plug does look like it is slightly rich but for the most part the burn is ok

I gather you mean fresh oil on the outside of the spark plug from leaking tube seals. One plug does look like it is slightly rich but for the most part the burn is ok

Yep, fresh oil on the outside of one of the plugs. But mainly on the thread end / bottom of the plug. With only a little on the other end of the plug, on the insulator just above the "nut", you can just see the yellowish discolouration in the top pic. And the same plug is also very black on the end, as shown in the bottom pic - the plug on the far right.

I can't see any oil in the tube or on/in the connecting tube, so it doesn't look like a leaking tube seal to me.

So three possibilities I reckon - a minor tube seal leak so small it's hard to see, one cylinder running a bit rich (but why just one?), or worn piston rings in that one cylinder.

I've just clocked up 139,400k but I've not seen or heard of any reports of 380 tube seals leaking this 'young', AFAICT the 6G75 tube seals are much better and last much longer than the 6G74 tube seals.

I trust your judgment Mal, so whatever you say is the most likely cause I will go with.

Oil in the cyl will burn and not get past the thread

Oil is from tube seal. Small amount and gravity makes it run down. If rings you would be driving a smoke machine and none would be external

Tube seals are the same, is the cover that is slightly different thus less likely to leak but does happen

Oil in the cyl will burn and not get past the thread

Oil is from tube seal. Small amount and gravity makes it run down. If rings you would be driving a smoke machine and none would be external

Tube seals are the same, is the cover that is slightly different thus less likely to leak but does happen

Thanks Mal, so dodgy tube seal it is.

Worth replacing all six tube seals now, let it go for a while, or don't bother?

I'm planning to buy a new car in roughly two years time, so I'm thinking I'll just let it be.

[QUOTE=TreeAdeyMan;1563514]
(and not just you Max!)

OK !!

No is oil burning on the hop spark plug from the run down caused by the leaking tube seal

No is oil burning on the hop spark plug from the run down caused by the leaking tube seal

OK!! Good to know.

head down to repco and grab a rocker cover gasket and tube seal set, $40 for a set and just replace them all (you'll need 2 to do front and rear).

For interest sake, I just paid a fortune to have my Pajero 3.5L engine dismantled & rebuilt after I dropped a washer in the intake. Yes - I know it wasn't easy! Anyway, after paying a fortune to have the job done, a horrid rattle was still there so I took it to another mechanic. When we dismantled the engine, we took the plugs out. No 1 and No 3 plug tubes were full of oil. This, despite the fact that they replaced the rocker cover gaskets and the plug tube seals. The engine had done only 2 km since being 'overhauled'.

The used Silastic EVERYWHERE, and lots of it. As far as I can see, the last thing you should do with new plug seals is to use silastic, because the plug seal requires some compression, and if you have silastic under the main rocker cover gasket, it will sit too high and not give you compression on the seal.

Incidentally, the rattle was caused by a part of the spring washer which they did not clean out, and it got into the No 4 piston - nest to the original No 6 piston which was damaged in the first place. NOT HAPPY!

Question for Mal.

I checked my front bank of plugs just now, and the far passenger side plug was definitely oily (again).

So it's pretty well certain that plug seal is leaking.

But the other two front plugs are OK, and when I changed plugs a couple of months ago all three rear plugs were OK, no sign of oil.

So odds on I have only one leaking plug seal.

Is it worth replacing all the seals to fix one leaking seal?

Or just let it go, one leaking seal is no biggie?

PS - Mal - shouldn't this thread be in the 380 section instead of the 3rd gen section? Took me ages to find it!

@ Erad: Surely it's not too hard for a mechanic to tell if has fished out a whole washer or just a part of one? The mind boggles!

Anyhow . . . . oil on the outside of a spark plug has to be tube seals, and if the tube seals are recent, there may be a problem with that particular tube seal, or where it sits on the spark plug tube or the rocker cover itself. Definitely needs a closer look, rather than just replacing the seal again.

I replaced a set (for the first time ever) and thought about the silastic, but the lips on the new seals are very pliable and silastic would not help any, rather, it would stop the seal lip from conforming to the underside of the rocker cover.

I would suggest (although I am not Mal) to replace the front bank rocker cover and 3 tube seals. Simply because spending a couple of hours pulling it all apart and putting it back together for 1 $4 tube seal would be silly considering doing the whole bank would cost less than $30 with little extra time spent.

To do the rear would be false economy as there is no immediate sign of leaking.

Tube seals, do them with a kit, the kits come with rocker cover gasket and tube seals and I sell them posted for $40

Erad, seems that the first place was a little, shall we say, dodgy. They knew you were pulling down the motor so should have found all the bits. The silastic, if anyone working for me used silastic in this shop they would be sacked on the spot. Issue that most dont even comprehend is that sealant will NOT stick to the rubber gaskets anyway so is a waste. The fact they used silastic on a motor fitted with an oxy sensor is bad enough, there is RTV for use on these motors, the fact they used it to seal up cover gaskets? Perhaps they did not rebuild the motor at all in the first place

Like i have said in a previous thread, better to replace spark plug tubs and tappet cover gaskets when your replacing spark plugs. Saves all the hassel of taking all that gear off the engine to do it AGAIN.

Tube seals, do them with a kit, the kits come with rocker cover gasket and tube seals and I sell them posted for $40



Mal,

Yep I know about your kits and if I want/need one or two of them I will get yours.

Maybe I wasn't clear enough, but my real question was "should I go ahead and buy one kit (or two) and replace three (or six) tube seals, just to fix one leaking seal, or is it not worth the expense & mucking about when only one of my six seals is leaking (and it's not leaking a lot)?"

My feeling is that if you recommend I replace that one leaking seal, then I might as well go the whole hog, get two kits and do all six.

If one seal is leaking now then the other five can't be too far away.

Removing the upper intake plenum to get at the rear bank is no biggie to me, I've done it five times now.

Mal,

Yep I know about your kits and if I want/need one or two of them I will get yours.

If one seal is leaking now then the other five can't be too far away.

Buy the two kits and see what you find when you do the front bank. Doesn't hurt to have spares handy even if you don't need them right now.

What age are the current tube seals?

I'd still be temped to see why the leaky one is leaking, ie is there a defect in the seal, or it's mating surfaces? Spark plug tube in good condition? (etc)

Check too that the lips on the non-leaking seals are still flexible, if they have gone stiff with age and heat, do the whole lot. On the 3.5L engine it is quite obvious when they have gone hard and are squashed.

Just my 2c worth . . .

Buy the two kits and see what you find when you do the front bank. Doesn't hurt to have spares handy even if you don't need them right now.

What age are the current tube seals?

I'd still be temped to see why the leaky one is leaking, ie is there a defect in the seal, or it's mating surfaces? Spark plug tube in good condition? (etc)

Check too that the lips on the non-leaking seals are still flexible, if they have gone stiff with age and heat, do the whole lot. On the 3.5L engine it is quite obvious when they have gone hard and are squashed.

Just my 2c worth . . .

December 2005 build, first registered July 2006, so coming up to 7 years 'on the road'.

ODO currently on 142,066k.

If they are the originals, they have done well. Definitely do the whole lot, seals and gaskets.

Bought a TL last year, 136,100 km. Gaskets and seals leaked like anything. Clean engine when I bought it, oil everywhere 1 week later. lol

(And use a torque wrench on the rocker cover bolts, 3.5 Nm - a $40 eBay 1/4" drive torque wrench will do if you don't have one. Criss - cross pattern, go over them several times as the rocker cover gasket squashes down a lot.)

OK, I've bit the bullet and ordered two sets from Mal (2 rocker cover gaskets and 6 tube seals).

I've just corrected the torque wrench settings in my above post. I put 10 Nm, should be 3.5 Nm for the third gen rocker cover bolts. Check the manual but I imagine the 380 is the same.

OK, did the front bank this morning, will do the rear bank over the weekend.

All three plug tube seals were hard and a little brittle.

Two of them were 'pushed in' on one side, so they were D shaped, the other one was perfectly round.

Funny thing is it was the 'good' one that was leaking and not the other two.

The old rocker cover gasket was a real PITA to get out. The two ends came out OK, but half of each side was stuck hard, kinda burnt on.

Has to scrape it out bit by bit with a screwdriver.

One question.

Should I take it for a run, get it good and warm, then recheck/retighten the rocker cover bolts?

Assuming the gasket will soften and 'give' a bit when it warms up.

OK, did the front bank this morning, will do the rear bank over the weekend.

All three plug tube seals were hard and a little brittle.

Two of them were 'pushed in' on one side, so they were D shaped, the other one was perfectly round.

Funny thing is it was the 'good' one that was leaking and not the other two.

The old rocker cover gasket was a real PITA to get out. The two ends came out OK, but half of each side was stuck hard, kinda burnt on.

Has to scrape it out bit by bit with a screwdriver.

One question.

Should I take it for a run, get it good and warm, then recheck/retighten the rocker cover bolts?

Assuming the gasket will soften and 'give' a bit when it warms up.

Pretty much the same way I found my TL tube seals and cover gasket.

I wouldn't retighten the bolts (assuming you have them on 3.5 Nm) as you won't be able to do that with the rear bank later. On the other hand, if some time in the future you do spark plugs, that might be a good time to run the 10 mm torque wrench over them again.

Just discovered another trap for young players, the hard way.

Did the rear bank this morning, new plug tube seals & rocker cover gasket.

Put it all back together, headed off down the shops, and two immediate problems.

A bit of smoke from the engine bay and what smelled like burnt rubber, and the go pedal did nothing. Felt like there was a brick stuck under it.

Coz it was cold it was idling at 800 rpm so it was driveable in 1st & 2nd gears.

Chucked a U-turn, back into the shed, head scratch time.

Popped the bonnet, started it up, a bit of smoke coming off the rear extractors, figured out it was burning oil and not burning rubber.

Decided that before I pulled everything off again it might pay to plug my trusty OBD2 scanner in and check for error codes.

Hey presto, three new codes I had never seen before.

0122, 0222 and 0638.

All related to the drive-by-wire throttle.

Eureka moment!

I had forgotten to reconnect the drive-by-wire throttle electrical plug to it's socket underneath the throttle body!

What a bozo!

Plugged it back in, good as gold, and no more smoke or burning oil smell either.

Worked out than when I popped the rocker cover off (which took a bit of effort coz it was stuck real tight) it dropped a bit of oil down the back of the block onto the rear extractors, and it was now all burnt off.

The OBD2 scanner has saved me heaps of time, money & effort over the years.

Moral of the story - whenever you reinstall the inlet manifold off a Magna or 380, triple check that every hose and electrical plug is reconnected!

Oh, yes, almost forgot.
Give the car plenty of time with the engine off - preferably leave it overnight - otherwise oil from the rear rocker cover will leak down onto the exhaust and smoke afterwards. lol
Did mine hot, took quite some time to clear the blue smoke. Front didn't do that. Next time I will place a rag across the back to catch the dribbles.