Thanks in advance; what can you read from the appearance of these spark plugs I just pulled from an 80? Normal?
What story are these plugs trying to tell?
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Look clean and normal to me. Electrodes look worn based with the corners looking soft and not hard edges like they are when new so replacement seems appropriate.
I'm not sure if the gunk on the rim of the topmost is indicative of anything but if it's pretty soft and easy to wipe off it could have been picked up from inside the spark plug tube and may mean that you have a leaking seal on the corresponding spark plug tube seal that lives in the valve cover. If that gunk is baked on and hard to remove then it more likely came from operating conditions in that cylinder and there may be a source of oil leaking into that cylinder (valve stem seals?, oil rings?).
I'm not sure if the gunk on the rim of the topmost is indicative of anything but if it's pretty soft and easy to wipe off it could have been picked up from inside the spark plug tube and may mean that you have a leaking seal on the corresponding spark plug tube seal that lives in the valve cover. If that gunk is baked on and hard to remove then it more likely came from operating conditions in that cylinder and there may be a source of oil leaking into that cylinder (valve stem seals?, oil rings?).
They look fine, but those are basic copper "v-power" plugs. If you want to replace them my personal preference on the 1FZ is the Denso IK16-5303. Very clean burning spark plug and lasts much longer than the copper plugs you have there.
I'm genuinely too embarrassed to show the plugs I pulled from mine last week. I just hadn't gotten around to the plug/wire/cap/rotor job and I wasn't experiencing misfires, so I didn't worry about it until the coil wire shocked me. #4 wire came apart and left the terminal on the plug which wouldn't allow my socket to go deep enough, so I had to fish in there with a set of forceps. #6 felt like it might come out with the head threads wrapped around it (no issues, it just felt off). Then the lot of them looked like they'd been installed in a Nova Scotian fishing boat for about a decade. Pretty sure the PO had no knowledge of antiseize or dielectric grease. To top it off, in the process I noticed my heater valve was just starting to drip occasionally, so that part is on order...
On the upside, the color of the plugs was good, though they were severely worn. It all looked like it was in pretty decent shape until I dug into it.
No harm done, but I'm mentally reexamining the items the PO had mentioned he'd done recently.
On the upside, the color of the plugs was good, though they were severely worn. It all looked like it was in pretty decent shape until I dug into it.
No harm done, but I'm mentally reexamining the items the PO had mentioned he'd done recently.
curious about what causes the spark plug threads to get so oily. I can see the top of the plug getting oil coming down the tubes, but I can't imagine blow by is working its way uphill from the combustion chamber.
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^ I'd bet it's just oil seeping down from the tubes when you pull the plugs out. The valve cover seals get cooked and leak like a sieve. I just did my plugs and seals and plug leads a couple of months back. Lots of oil pooling due to cooked seals. Plugs were dripping oil when I got them out - that's how much oil gets past the seals pooling and waiting for the plugs to come out. This is the second time I've done the seals, they appear to last maybe 10 yrs (if lucky).
If that oil was coming up the combustion chamber, you would be creating a 007 smoke screen behind you as you drove down the road
And my plugs gaps were nasty, the center electrodes were nearly worn flush - I've plead guilty of not having replaced the plugs sooner. I had a set 12 new ones (3 sets of 4) waiting to go in for what I thought was 6-9 months - turns out more like 3 years
Certainly a testament of modern engine management...
cheers,
george.
If that oil was coming up the combustion chamber, you would be creating a 007 smoke screen behind you as you drove down the road
And my plugs gaps were nasty, the center electrodes were nearly worn flush - I've plead guilty of not having replaced the plugs sooner. I had a set 12 new ones (3 sets of 4) waiting to go in for what I thought was 6-9 months - turns out more like 3 years
Certainly a testament of modern engine management...cheers,
george.
This is what mine looked like after about 4 years turbo’d. @alia176 and I were talking about them. Tube seals are only 4 years old but I know I have blow by and positive crankcase pressure so oil will find its way out.
One more vote for Denso Iridium over standard plugs. Iridium Power lasts longer IME (75,000 - 100,000 miles in a FZJ80). For even longer life, Denso Iridium TT (Twin Tip) which has a thin Iridium post and a button of platinum on the side electrode, can go 100,000+ miles.
FWIW
FWIW
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