Got oil on top of your spark plugs??
 

Hopefully this gets sticky'd. There seems to be some debate over WHERE the oil comes from. I'm here to settle this once and for all, as I am tired of replying over and over again to this simple problem that anyone can repair very easily.

First of all, many DOHC engines have spark plug well seals. This, however, is not the case on the 87-92 7M engine.

Please refer to my custom diagram. When it says (color, shape) that is what I'm talking about. Pretty straight forward.

http://i44.photobucket.com/albums/f2...fe/diagram.jpg

Go buy a 14mm allen head socket from napa. Take the No.3 cyl head cover off and throw it into the garbage. Now divert your attention to my shitty diagram:
If you have oil here (green arrows) then it is possibly coming from 2 places. Everyone says, "It's coming from the valve cover gaskets" (red boxes) which, I too thought when I was new to supras. So I replaced the valve cover gaskets, yet the oil was still "appearing" in the spark plug gallery. Not as much as before, but it was still appearing. No track marks from where it was coming from, just a puddle. It was very frustrating. I then discovered (through no help of any forum, they all said it was valve cover gaskets) that the No. 3 cylinder head cover BOLTS (yellow circles) were leaking. They are 14 mm allen head. You can A. Go to the dealer and get a new No.3 cylinder head cover (its a cover AND a gasket all in one, bad design) or B. bring 1 of your 14mm allen head bolts to an auto parts store and match up an oil drain plug gasket that fits. That's what I did, I used red ones (yellow circles), cuz it matches the red lines on the valve covers.

Hope this helps.

Very well done ^^^.
Also, if you want to keep the old #3 gasket/cover on the motor,(and not pay the $38 for a new one), you can apply a little silicone gasket sealer (or FIPG) at those big threaded plugs.

Note: if enough oil leaks into the spark plug boot area, it will start causing misfires.

so can you help us a little further and tell us what the part number or size of those gaskets are??? I am having that problem myself and I feel it is more then the valve cover gaskets!!!

I don't know what the part number for the no.3 cylinder head gasket is, because I didn't replace mine I threw it in the garbage because that is what it is- garbage.

Since you asked, I went to NAPA and got 4 gaskets Part # 704-1076.

Wow, I thought you guys had enough sack to bring 1 of your 14mm allen head bolts to a parts store and figure it out for yourself, I had to. I guess I have to spoon feed information to you people.

Anything else I can help you with?

i got oil showing up on top of my valve cover

hey IHateHacks
 

hey..i dont have oil on top of my spark plugs buh i have oil ontop of my valve cover and it looks thick too im prolly going to clean it off on tuesday to see if it comes back or not..buh wha could that mean

check your pcv system.......

so i have a black thing going across where all my plugs are, is that the spark plug well seal? or is that just like a cover and the problem is deffinetly the cylinder head cover bolt seals? Thanks.

If you read the first post, I said there are no plug well seals on a 7M. Go look at any other OHC engine and you will see that the spark plug wires go through the valve cover. Those are where plug seals are. Do our plug wires go through the valve covers? No? Then we don't have spark plug well seals. That black thing is your No.3 cylinder head cover AND gasket. Its a one piece combination cover and gasket. See the picture in the first post? See the yellow circles? Those 4, 14mm allen head bolts are what holds the No.3 cylinder head cover in place. They thread into the oil gallery. That is where the oil comes from. Those 4, 14mm allen head bolts are where the oil comes from. Should I repeat it 3 times like they do in commercials? I don't care how you do it, you can RTV your stock No.3 cylinder head cover like some cheapskates do, or you can throw your No.3 cylinder head cover in the garbage and use oversized drain plug gaskets like I did, or you can go get ripped off at the dealer for a new No.3 cylinder head cover.

I guess I should have warned you guys in the first post, you must have some kind of mechanical knowledge to do what I did, because obviously people are still confused as to what I'm talking about, even with pictures. I bet if I showed you in person, you still would not comprehend. I guess thats why Toyota designed the head like this, to confuse people and make them bring their cars to the dealer. Job security.

could oil also be coming from the three 14mm allen bolts that are right next to the spark plugs??

and also is it necessary to have the no3 head cover on or can you run with out it?

thanks for the post, im having this problem and i didn't know what it was till i found this thread.

Those 3 14mm allen head bolts right next to each set of spark plugs (1 0 1- 1 0 1- 1 0 1, 1= spark plug 0= 14mm allen head inbetween the plugs) hold coolant. Do not take those out unless you have coolant in your spark plug wells. I've never seen or heard of those 3 leaking though, so I wouldn't worry about them.

The no.3 cylinder cover is a gasket so you can't just take it off without using either another no.3 cylinder head cover or oil drain plug gaskets.

okay cool, just wanted to double check.
thanks a bunch man, now i dont have any oil on top!

does this apply to oil on the spark plug tip? the other day my ghetto rigged ic piping popped off. car ran super rich for about 20 feet until i could get to a gas station. after that, car was hesitating under load, thought it was knock so retarded the timing alot...no help. by proccess of elimination, must be a fouled plug right? went and dropped $70 on denso iridium plags and but them in. when i took the old shitty autolites out, plug #6's tip was covered in oil. it was kinda hard to tell where on the plug the oil was since my buddy kinda smeared it with his fingers. first time under load after denso install...same hesitiation. now, i dont have the spark plug socket with me right now but im pretty sure when i pop #6 off tomorrow, it will have oil on it. does this stickey apply???? thanks.

Because they will bottom out if there is not a 2mm layer inbetween the 14mm allen head bolts and the cylinder head. You need to use either a new no.3 cylinder head cover or drain plug gaskets or you will strip the aluminum when you torque them to 13 ft/lbs.

Currently in the middle of fixing this problem myself and need a little guidence i guess, read through all the posts and i think i understand what i need to do, picking up those gaskets on monday.


I took out the 4 14mm bolts things, now how do i remove the valve cover gasket? or does it just pop out, i didnt want to try and force it.

all i have currently removed is the 3000pipe, and that thortle thing and some IC pipes, do have have to remove the two black covers on the side with the red lines down it?

theres one bolt towards the rear of the engine going through the gasket, if you havent removed that you need to, otherwise just pull the gasket out, if its catching anywhere then just figure out what its catching on and undo it. You just get rid of that gasket all together

Maybe just dumb luck...but while doing my head gasket replacement, I also replaced (among many other things) the No. 3 cyl head cover with a new OEM ($52.00) from Toyota dealer. I felt at the time maybe this was a waste of money. But after reading these posts I think it was money well spent. No leaks. No problems. (and I run hard on road courses)

That elusive part number for this famous No. 3 cyl head cover I will donate to the cause for a Ron Paul vote...Toyota Part No. 11219-42020

i bet the purpose is to keep debris and liquids out of the spark plug tubes since its so hard to get out once its in there, and if you remove the plugs when theres stuff in there itl fall into the cylinder.

There are two (2) valve covers and one (1) 'spark plug cover'. However, the Toyota manual, and probably your Toyota parts guy will list them as the No.1 and No. 2 Cylinder Head Cover Gaskets for what we Americans usually refer to as valve cover gaskets. The 'spark plug' cover/gasket is refered by Toyota on our car as the No. 3 Cylinder Head Cover.

So...the No. 1 and 2 are traditional valve cover GASKETS, to be used between the two valve covers (No. 1 and 2 cylinder head covers) and the head to seal, while the No. 3 Cylinder Head Cover is one complete replacement part/gasket/cover but not actually a valve cover...goes on top of the head, over the spark plugs, between the two valve covers.

If you are going to work on your own car and don't recognize a traditional valve cover you MUST get the Toyota Supra Repair Manual (TSRM). Even for those who do know cars will most likely have and use it frequently. (I recall from somewhere in this forum the TSRM is available on-line. If you can find it go to page EM-33 for the 1988 Turbo for a nice picture.)

Scan backwards on this thread for lots of info on this topic.

To elaborate on post #7:

There is a third place it can come from... That's the PCV plumbing. If you've got severe blow-by issues the quantity of oil passing through the crankcase ventilation system can be quite high and quickly degrade the couplings giving the oil another escape route than the intake tract. It's not common and usually takes quite some time but it does happen often enough that you shouldn't disregard the possibility. I've seen this twice. It's a rather nice surprise as it's the easiest thing to take care of, but I usually replace the valve cover seals anyway (as I've probably already bought them :P ).

Don't forget the FIPG at the right angle of the #1 cam caps.

Thanks for this post! Extremely helpful for me, as a new Supra owner. Went to purchase mine, went to pull a plug as part of my inspection and found the wire saturated with oil along with the entire trough between the 2 valve covers.

http://img.photobucket.com/albums/v6...0602032020.jpg

Thought it was the valve cover gaskets, but them found this post. Ordered the stock #3 cyl cover from my local toyota dealership (prefer to keep it stock) and no oil since! Fabulous.

I also got the drain plug gaskets from Napa, as the OP had recommended, but decided to stick with the OE gasket, because I preferred the material for this application (rubber with the aluminum washer, vs the fibrous material of the red gasket that the OP described) and figured that perhaps the extra support around the plug wires helped something?!?!?!? Those Toyota engineers put it there for a reason? Who knows. Anyways, doing great now. Thanks.