pattycakes77

iTrader: (2)

i've got a '98 4runner with the 5VZFE V6, 96k mi.

i hadn't driven it only once in the last 10 days and it's been single digits for highs and i think i heard it was like -20 the other night. so when i drove it the other night i smelled burning oil, but it was dark and i couldn't see, got it home quick and parked. next morning i saw a little bit of oil leaking onto the exhaust manifold and i figured i would need some new valve cover gaskets when it warmed up enough for me to do it. so, today i notice the burning smell some more and decided to check it again and make sure my oil level was ok, and i noticed that my #2 #5 and #6 spark plugs were leaking oil out of them from the valve cover, right under the boots.

not being a mechanic and searching around on yotatech i've seen some posts about the ring around the spark plug hole going bad and leaking oil. is it reasonable to think that's it or could it be something worse, like a bad piston ring or something? and, 3 leaking all of the sudden at once, is that likely from the extreme cold or perhaps they are just due? i did switch over to amsoil full synthetic over a year ago and i've heard that sometimes synthetic can cause leaks in certain seals. if it's just a bad seal, valve cover gasket, or rubber ring around the spark plugs, is this something i could hold off on until the weather goes above freezing to fix and just live with the smell?

i really just want some decent info to have under my belt for tomorrow. i called the stealership and they will take a look at it and diagnose "for free", and i want to know some possible culprits to discuss with them so they don't try anything crazy. spendy car repairs are not in the budget right now since i just lost my job. i'm crossing my fingers.

thanks yota gurus!

hanksyota

the exact same thing happened to my buddy here in CO. check out the ttora thread. and i'll sum it up for you, for those who hate linkers.
http://ttora.com/forum/showthread.ph...highlight=jade

looks like its one of these things:
frozen or bad PCV valve (causing pressure to build and oil to get by rings)
spark plug tube seals went bad (remove valve cover to get to these)
piston rings went bad (unlikely all at once, but could be)

good luck.

ROCK LIZARD

Sounds to me like leaky gasket seals around your plugs like you mentioned. As you probably know, cold can shrink things!

If oil were leaking past your piston rings it would be burned in the piston combustion chamber and you would see smoke coming out of your exhaust.

As far as synthetic oil causing gasket leaks--some claim it doesn't happen, others say it does. I have had it happen to me after changing from dino oil to synthetic, so I believe it does.

Valve cover Gasket replacement isn't hard to do but can be a real pain on some V6 engines because of limited access and things that need to be removed to get the valve cover off. If you don't have a FSM or after market service manual, or don't feel like working in sub-zero weather, then it's to the dealer or other trusted shop. The leak will make a big mess on your engine but won't do any real damage unless it gets on your belts. Check your oil level frequently if you wait any length of time. Good luck.

hanksyota

yeah, like Rocklizard said, metal contracts/expands with heat/cold. might even go away with warmer weather.

pattycakes77

iTrader: (2)

thanks a bunch. i did just replace my PCV last week but i got it from the auto parts store, guess i might pick up an OEM one and see if that helps. if they tell me it's the plug tube seals i think i'll just do that myself, even though it's gonna be freezing out there, talk about shrinkage! i'll replace the PCV again, and if that doesn't fix it i'll just live with it until i can get out there and really check it. basically, i'm hoping toyota will do the diagnosis and i can do the fixing. btw, my valve covers look exactly like that pic on ttora, except not all my plug tubes were leaking.

thanks for the suggestions and the link there! will advise tomorrow about the prognosis and fixes.
thanks,
patrick

One_96TR4

Sounds like a leaking valve cover gasket. Had this happen on a few other cars, changed the gaskets and no more leaks!

mkgarrison5

leaking gaskets in a toyota at 96k miles?? has this think overheated at all since you owned the vehicle?

pattycakes77

iTrader: (2)

no overheating. it's not the head gasket or anything, just the valve cover gaskets which seems to be a common problem after some miles.

i did get a call from the dealership today and they told me that it was the seals to the spark plug tubes that need replaced. he told me it was probably due to them being 10 years old and the extreme temps we've had. also told me that in order to get to them they had to take the valve covers off and those would need replaced as well. $100 in parts, $350 in labor. i'm going to buy the parts, and a new PCV and see if the weather improves enough for me to do it. if not, i'll call around but i might have to have them do it just for the fact that i want it done right and with a warranty if they decide to leak again from the weather. just thought i'd pass this along to anyone else that might have this problem too.
i swear, nothing ever happens to my 4runner in the summer when i can do the work myself, always has to be in the dead of winter although, this is only problem #2 since i owned it the last 5 years and i like that track record.

nc t4r

I had my valve cover leaking as well and did a search on it. Found a thread that talked about checking the valve cover bolts as they come loose over time. Checked mine out and sure enough, they were finger tight at best. Using a torque wrench tightened them down, and no more leaks. Just something to check before spending the money.

hanksyota

at least you got it figured out. good to hear. we were close!!

pattycakes77

iTrader: (2)

got back from the dealer, a good 6 miles away from home, popped the hood and expected to see oil on the valve cover by the plugs... NOPE! just old stuff, nothing real wet like the other day. not to say i'm going to let this go, but it is warmer today and things dried up a bit. still have some on the lower part of the engine where it leaked and didn't burn up on the exhaust. parts guy quoted me about $92 for intake gaskets, seals, and i'm not sure if it's the tube gaskets or the actual tubes themselves but they were lumped in there too. ordered a new PCV valve while i was at it. and, should i consider getting some new plugs or maybe even wires? don't know if the oil would affect all that stuff, plugs and wires were replaced in '04 with about 65K on the engine. i can't even check the plugs on the driver's side because of intake and hoses in the way, and the pass side has the coil packs on them, so inspection isn't super easy. but if the oil would affect the plugs, i've done that before and it would be an easy job, not paying the dealer for that.

thanks everyone, hope this helps others out down the road

MTL_4runner

From what I saw in the pics that is likely a combo of a clogged PCV and old valve cover seals. They are a little tough to get to (you need to take the intake plenum off) but it's a cakewalk to install them into the valve covers. All you need to do the job is the 6 spark plug tube gaskets, 2 valve cover gaskets and 2 intake plenum gaskets. Just tightening the bolts with old gaskets may work for a little while but the gaskets get very hard and brittle over time so retighteing the valve cover bolts is only a temporary band-aid fix.

Here's how to do it correctly:
http://www.ultimateyota.com/index.ph...28026#msg28026

pattycakes77

iTrader: (2)

Questions and answers:

1. is there an easier way to remove the old plug tube seals? i ended up ripping them to pieces and prying them off with flat blade screwdrivers and anything i could get in there without damaging the valve cover. i even tried to warm them up with a heat gun to soften them in hopes they would slide right off. it was quite the task.

Answer: not to my knowledge. after doing the driver's side plug tube seals, it turns out that the best way i could get them out was with a thin flat blade screw driver and carefully pry the old seal out trying not to damage anything or gouge the surrounding surface.

2. putting the new plug tube seals back on, what's the best way to pop those babies in there? should i put a little oil on the sides to make them slide better or would that affect them negatively? i tried to gently push on them with my fingers, screwdriver handles, and even tried a large socket to tap them down a bit but nothing really worked all that great. i got them as far down as possible, about flush with the opening from the underside of the cover, but they still look like they are sitting higher than the old ones.

Answer: after doing one side, i tried it again but first lubed the edges of the plug tube seal with some motor oil. they slid in pretty well, but then had to be tapped down a little more. to do this, i suggest either using a socket that is the same diameter of the plug tube seal or, i used my billet oil cap that was approx the same size and gently tapped down around the radius of the tube seal. this left no damage to the seal itself and got it in place pretty easily.

3. and lastly, anyone have the torque specs for the valve cover bolts? i don't want to mash them down and ruin the gasket but i also don't want them to leak being too loose. of course, my trusty Chilton's manual doesn't give any useful information about anything. guess i'm gonna keep an eye out for a FSM.

According to another post, the torque spec for the valve cover bolts is 53 inch pounds. and according to the Chilton's manual, the intake plenum torque spec is 160 inch pounds.

thanks!

pattycakes77

iTrader: (2)

searched around a little, i guess the FSM for those valve cover bolts says to tighten to 53 In/Lbs according to THIS thread.

as for taking out the old plug tube seals, i'll just do what i did yesterday, but this time i'm going to try a little oil around the edges when i tap the new ones in.

one last question for now... yesterday when i did the passenger side, the last plug tube closest to the firewall had about an inch of oil submerging the plug. i took a paper towel and tried to soak up as much as i could but didn't get all of it. and while i'm doing this job, i'm replacing my plugs and wires since they are about due. so, when i took out that spark plug, some of the left over oil i couldn't soak up drizzled down into the cylinder. after i got everything put back together, of course i was burning oil out the exhaust. is this something that will just burn after a drive up the street and be normal again or did i just cause serious harm to the engine?

thanks

JHRRLD

That oil should just burn off rather quickly, won't damage your engine at all IMO

pattycakes77

iTrader: (2)

good to know.

now, i'm having trouble finding anyone local that has a torque wrench in Inch Pounds! i've called everywhere and all they have are foot pounds. but, i have a question about that. since there are 12 inches in a foot, if i set it to 1 ft/lb would that be just like 12 in/lbs? i know it wouldn't be exact, but if i got it just under what i needed and then slightly snugged it would that work? the valve cover bolts are supposed to be 53 in/lbs and Chiltons says "snug", but then i have the intake plenum bolts Chiltons actually lists them as being tightened to 160 in/lbs.

anyone used a torque wrench rated in foot pounds and just done the math to convert to inch pounds or is this a bad idea?

Answer: Turns out you can just do the math and use 1 foot pound = 12 inch pounds, but when your goal is 53 inch pounds and your torque wrench goes up in 1/2 ft/lb increments it's not very accurate. however, a little over or under on the valve cover bolts probably wouldn't hurt much. i had a hard time finding a torque wrench that could measure down to 53 in/lbs, eventually found a friend that had a really nice digital torque wrench, but that still only measured 60 in/lbs and up. as Chilton's says, "snug the bolts" so i don't think you need it exactly at 53 in/lbs.

Man4God

Whatever you do, go and tighten up all the valve cover bolts first. THAT will probably stop it. My truck had a little oil leaking around the valve cover and after seeing a thread on here about how the bolts mysteriously walked their way loose, I tightened them up. Sure enough, they all needed a couple turns to tighten them up. Just don't over tighten. Just snug them up good.

pattycakes77

iTrader: (2)

well, after a couple delays this morning, i got started on the driver's side at around 1pm. i should have just done both the same day, so keep that in mind if anyone else is thinking of doing this. it's just easier to both at the same time than what i did and take a bunch of stuff off and re-assemble and then have to take most of that off again anyway to do the other side.

everything went just fine. just a few minor hiccups... i lost one of the grommet washers for one of the valve cover bolts, i broke one of my retainer clips for the grille while i had it off so i could kneel on the bumper while in the engine bay, and i misplaced a little stop off for the vacuum system near the throttle body. but, it's all together and it runs great, no weird noises, and no CEL! once i cranked it up and everything was running fine with no issues, i pulled a Billy Madison and said "I am the smartest man alive!". i know, this wasn't a very hard thing to do, but after 10 years of not having to dive into the engine at all, it was pretty amazing that everything went right and went right the first time too!

some other notes... there were plenty of vacuum lines, hoses, throttle cables, electrical connectors, ground points, and brackets that had to be removed or loosened to get the intake plenum(s) off to access the driver's side valve cover. then, to get to the top bolts of the valve cover near the intake manifold, i had to do some more loosening and finagling to move that for access to the bolts. the bottom bolt closest to the firewall on the driver's side required a long extension and one of those swivel socket adapters since the master cylinder was in the way along with a bunch of electrical/fuel/vacuum lines. and one surprising thing i discovered was that both pieces to the intake plenum were pretty dirty. the top one was slightly dirty on the inside, the lower one looked like old coffee caked on the inside, and the intake manifold was the darkest! i did a pretty good job of cleaning the top two pieces since they were off and i could spray carb cleaner and take a toothbrush to them but the intake i just wiped out with a lint free cloth soaked with carb cleaner, no brush since i didn't want any bristles or gunk falling down there. don't know why it was so dirty, i remember the intake from my old celica only needing a slight clean when rebuilt the engine after 130K miles, nothing like what i saw today. the plugs were a bit gunky too, changed 30k miles ago. i went ahead and bought new denso plugs and wires from the dealer the other day and did that today while it was all apart, one less thing to do in spring.

i'm glad it warmed up to be in the 40s the past few days, made this project a whole lot more pleasant to do and i saved about $350 in labor costs the dealership quoted me. it was a challenge for me, but i was a little rusty on engine work, took me about 6 hours total including a tool run to the hardware store and a couple breaks for a drink and snack. not a bad days work. it was also nice that my friend came through and let me borrow his Snap-On digital Torque Wrench that he paid $450 for and hasn't used yet, pretty spiffy tool!

i took pics of various stages of engine disassembly and the gunk on the plenum and i'll get around to posting those in the next day or so. maybe the pics will give some one a better idea of what is involved in replacing the valve cover gaskets seals.

thanks again for the advice everyone!