Is valve cover #3 essential and is there a way to keep oil out of the the spark plugs. I bought another 89 and changed the plugs' The next day it seemed like they were fouling. this 89 has the #3 valve cover which my other 89 does not. The latter is the one I rebuilt and cannot get spark. Can the oil get in to the comb. chamber past the plugs from the valve covers? Can anyone tell me the correct plug and gap for 7m-gte? The book says 31 but the ones I pulled out were gapped at 40 and it seemed to run ok. It had a slight miss at idle but now it misses terrible with the plugs app-5503 autolite. Those are the ones the store gave me. I gapped them at 35. I could really use a hand with this one. Thanks.
#3 valve cover, essential?
- Thread starter CHRIS EICHMAN
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autolites are 1/8'' shorter than NGK's and can give you a bad spark.
i dont run the 3rd cover, but thats because i plan to go COP in the guide in this section of the forums.
plug gap is suppose to be at .31, dont set it any way else. make sure your timing is right.
you want NGK copper plugs, they take a beating and keep on sparkin.
i dont run the 3rd cover, but thats because i plan to go COP in the guide in this section of the forums.
plug gap is suppose to be at .31, dont set it any way else. make sure your timing is right.
you want NGK copper plugs, they take a beating and keep on sparkin.
Aurolite 5503 plugs are the correct length...it's the 3923 plugs (that seem to be so popular) that are 1/8" shorter. The 3923's can/have arced due to improper wire contact.
The plugs need to be gapped at 0.031". (0.31" would be a tad bit wide)
The plugs need to be gapped at 0.031". (0.31" would be a tad bit wide)
Oil cannot get past the plugs to foul anything in the combustion chamber. That said, replacing your valve cover seals is still very worthwhile, it's possible to leak so much oil into the spark plug valley that the wires arc through it to the head material.
Many folks run without the third cover, so it's obviously not required. Personally I like it as it provides a lot more support for your plug wires.
Many folks run without the third cover, so it's obviously not required. Personally I like it as it provides a lot more support for your plug wires.
i have mine gapped to .028 i'v alwasy been told if your running higher boost the plugs should be gapped down some, other wise the spark can be blown out. so im guessing if your plugs were at .040 then they might have just been missing. try gapping them down to where they should be and see what happens.
As stated, gap to .031.
As far as preventing oil from getting into the galley and shorting out your plugs, I've heard of folks removing those big ol huge-ola bolts and reinstalling them with oil drain plug washers that you can find at any NAPA store.
My preference is to leave the 3rd cover on to prevent water and such from getting in there. And as Grim stated, it does hold the plug wires in place nicely.
As far as preventing oil from getting into the galley and shorting out your plugs, I've heard of folks removing those big ol huge-ola bolts and reinstalling them with oil drain plug washers that you can find at any NAPA store.
My preference is to leave the 3rd cover on to prevent water and such from getting in there. And as Grim stated, it does hold the plug wires in place nicely.
If you're leaking oil like that, then the two things that come to mind to me have already been mentioned. Valve cover gaskets, and the two large 14mm?? hex plugs on the head. Either can leak oil. If you haven't replaced the valve cover gaskets since you've owned the car, you may want to consider that, along with upgrading the valve cover fastners to some better clamping hardware. The hex plugs can have a permatex sealant placed on the threads and re-installed. I can't remember the name of the sealant off the top of my head, but it's around here as it was recently mentioned.
You mean the 4 large plugs
And they're sealed by the 3rd valve cover gasket (it's called a gasket for a reason). It's rubber over metal, and the rubber wears out and things leak, just like the other valve cover gaskets.
And they're sealed by the 3rd valve cover gasket (it's called a gasket for a reason). It's rubber over metal, and the rubber wears out and things leak, just like the other valve cover gaskets.
Poodles;1151337 said:You mean the 4 large plugs
And they're sealed by the 3rd valve cover gasket (it's called a gasket for a reason). It's rubber over metal, and the rubber wears out and things leak, just like the other valve cover gaskets.
Right. It's been a while since I've looked at my long block, or even the supra for that matter
I pulled the plugs and regapped them at 31 thou. The #6 plugs insulator was discolored and the ground strap showed no sign of heat. Also it appeared to have oil on it. It fired up with a little effort and idled smooth for a few seconds and then started to miss. I ran a compression test a few days ago and all 6 were above 150. How else would oil get into the comb. chamber if its not the rings? I also installed new plug wires so I dont think they are shorting out in the plug galley or whatever its called. Thanks for the info about sealing the 14mm allen bolts. Do the lower ones on the head leak as well ir just the valve cover allens. I guess it couldnt hurt to seal them all huh?
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Valve seals being bad could put oil into the combustion chamber. And something nobody mentioned either is there is a crush washer on the bottom of most spark plugs that is there to keep crap out of the threads. If that isnt there, its possible for some oil to get down in there, and it is also possible that you have cracked the ceramic in the plug and thus leaking oil down if your spark plug valley is that full of oil. What kinda plug wires are you running, and how new are they? Are you arking the wires to a ground source like the throttle linkage bracket? And is it only the #6 plug your having problems with, or is it both cylinders on that coil? pull the wire and use an allen wrench and ground it to see what is going on. You could have bad wires, or just a bad connection. The oil is prolly coming from the valve train.
CHRIS EICHMAN;1151428 said:
It would be HIGHLY unlikely a cracked plug insulator would allow oil in the cylinder.
#1 - It would have to extend past the metal base
#2 - the oil would have to be above the insulator
#3 - a crack like that would be very visible
Even with a missing plug washer, the threads on the plug would inhibit oil flowing down since it's not under pressure.
Might want to change the plugs, even though they are not that old. Or swap the #6 plug to another cylinder to see if it reoccurs.
I bet it's cold...very cold and very stupid, with a lot of background noise/radiation. A lot like what you would see on Pluto :biglaugh:
Fixed <IJ>
Fixed <IJ>
Thanks for all the input guys, I ran it around the block and noticed, when it was still cold, some steam out the exaust. that went away as it warmed up. when I got back and checked the oil it was looking a littlt cloudy. blown head gasket I figure. No other way to get water in the oil is there, besides a cracked block. is that right? I guess iI will wait till morning to hear from you guys. Let me know if Ishould rip it apart. thanks
Now that it's getting cold, a bit of "steam" on start is normal. Same for some condensation in the motor, especially if you do a lot of short trips. Water is a by-product of combustion and when the engine does not get good and hot, it doesn't get vaporized so the PCV system can get rid of it.
IJ.;1151458 said:
What the hell are you talking about? First off the weather here is nice and 65-70 out. second, what does that have to do with anything. Say I know nothing if thats what you want to do. But in all the cars i have had, and all the cars I have built, i guess I know a little something. If he has that much oil in his valley, then its possible for there to be a crack he didnt notice. Look at how deep the oil was on the socket. It couls have easily been over the metal base, and into the insolator. So its possible. The oil can also get in if the crush washer isnt there when the motor is running, because there is cylinder pressure there on the compression stroke, and vaccume on the intake stroke. Thus the ability to open, and vaccume oil into there thru the threads. Its unlikely, but possible. I have seen it in a few DOHC cars before. But I guess the 7M is nothing like any other car i have ever worked on. Because many people on here seem to try to discredit anything I say by stating everything I say has nothing to do with the 7m, when it happens to work on any other car. You can put and allen wrench into the socket in place of the plug on the plugwire and touch that to a bare metal surface to see the actual spark of the car. To find out if your ignition coil is bad, or if its the wire itself. And you can do that by swapping wires around. Its a hell of alot easier than replacing shit you dont know is broken. And a hell of alot simpler than checking ohm readings on a multimeter to check it all out too. But its a 7m so I am sure your going to tell me that doesnt work on this car (even though I know for a fact it does) I am clueless i guess, and all you other guys are like the rocket scientists that programmed the first mars rover. ( which was sent to my planet to study the surface )
rawmk3;1152299 said:
Because the things you say to do are so far out, it ignores what the likely cause really is...you say so yourself. No real knowledge, just a long run-on paragraph that make little sense and is very difficult to read. The more you post, the more "clueless" you appear to be.
A cracked plug causing oil to get in the cylinders is so remote, the planets would have to align for it to happen...read my post above (#13). And, in the case of a cracked plug, the misfire would be due to the plug, not oil. You choose to substitute your "technique" for what the factory manual says...you trying to tell me spark at the plug is good regardless of wire resistance? The wires could easily be bad, you would get spark like you described and would never know it without putting a meter on the wire.
What it looks like is you are substituting what you think you know in situations where you really do not know how it works. Then you talk down the use of diagnostic equipment saying it so much easier to do things your way...yeah, right...and the result just as accurate too I suppose. You've done this numerous times, and you wonder why your credibility goes down the tubes.
Then you go off on a rant touting your "experience"...what you're really showing is your ignorance. If you were the last mechanic on earth, you would not touch my car.
jdub;1152401 said:
Ok first off him stating the plug isnt firing at all means NO SPARK. Resistance in the wire or not, NO SPARK IS NO SPARK. You need to pay attention more.
Next, if the ceramic insolation is cracked, and there is that much oil there, the vaccume on the intake stroke will SUCK OIL INTO THE ELECTRODE. Thus fouling out his plug. So my statement is possible especially with 3/4 of an inch to 1 inch of oil in the valley like it showed on his plug socket.
The factory manual is based on factory procedures, and yet there are short cuts for everything. Perfect example, do you follow the factory recomendations for pulling your motor? Are you running all factory spec equipment? I'm willing to bet not. So evidently the factory ideals arent always accurate, and factory diagnostics does not normally apply to an average "home mechanic".
Put a mulitmeter on your wires, ok. That tells you if the wire has a crack and is arching (thus causing resistance) Try visually looking at the thing, that will tell you in most cases too. come after me all you want but the fact of the matter is, I can normally diagnose a problem without a multimeter, and its accurate when im dealing with my car.
A simple test is to put that wire on another cylinder, and test that. If it works, its not your wire. Same with the coil, if you put the coil on another set of wires and swap it around and it works where previously it did not, then its not the coil. And if you swap it with a known good coil (ie his 3-4 coil) and the problem persists in the #6 then you know its between the coil and the combustion chamber somewhere. Normally a wire, or plug.
The wire is likely if the miss is intermittant because the wires move, and if the problem isnt consistant its probably arching off something. If the miss is consistant and the plug keeps fouling out as he stated, I would check to find out why the hell there is oil getting on the plug. Be it bad valve seals, or oil getting down the threads. Sometimes the least likely is the actual cause, so dont try and talk down to me and say its impossible that im right. Im not telling the guy to tear his shit down, its all simple things to check.
But thanks again for trying to make it like i know nothing about cars. I mean I guess im ignorant about the general physics of a friggin motor. I guess the 7m motor is a magic motor that does not apply to the same basic concepts every other engine in the world does. News flash, all motors are generally the same. There are things that are different yes, but the same physics apply to every engine. A DOHC motor with a ton of OIL in the plug valley is not a good think. EVER. It causes a ton of problems. But you already knew that.
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