Valve cover gasket — Oil Leak from top of engine

[tmiron]

I have two oil leaks. One is from the oil pan and that should be a relatively easy fix ( knock on wood). The second one though is a bit of a mystery. It's bigger and seems to be coming from somewhere around the front end of the exhaust pipe opposite of the oxygen sensor. I think it's actually coming from somewhere higher up than that because there is oil residue everywhere. Any idea of where it might be leaking from or how to find the leak?

[timsrv]

Valve cover leaks are notorious for being hard to chase down. It's about the only thing in this area that would leak from up above. There's the power steering pump, but that's farther forward. Good luck. Tim

[tmiron]

Do you mean the gasket under the cylinder head cover?

1211

[timsrv]

Yeah, that's what Toyota calls it. Every other person on earth calls it a valve cover gasket :)>:

[tmiron]

Thanks! I figured, but just wanted to double check.

Just ordered this: http://www.stockwiseauto.com/product_info.php/products_id/1978743/Make/Toyota/Model/Van/Year/1984

Anyone have any suggestions on replacing the Valve Cover Gasket? Anything else I should do while tackling this project?

Thanks!

[timsrv]

You'll need to remove some vacuum lines and things before you can remove the valve cover. These will likely be brittle and crack, so it would be wise to have new ones ready. Also there's the PCV valve & the rubber grommet in the valve cover the PCV valve sits in. That grommet usually crumbles when messed with, and is best removed/replaced while the valve cover is removed. See picture below for part numbers:

http://i8.photobucket.com/albums/a23/timsrv/TVT%20pics/Engine/valvecoverhoses.jpg

The grommet (Dorman part shown above) is available at almost any auto parts store and is usually hanging on the "HELP" rack. There are also the 3 metal/rubber washers that help seal the valve cover around the mounting studs. These might come with the valve cover gasket (depending on where you get), but if not ask for them and they will have them (these are very common and used on many Toyota engines). Tim

PS: I looked at your link and it looks to me like the gasket you purchased comes with the metal/rubber washers.

[lamont]

I am getting ready to replace my valve cover gasket and was just curious about the spark plug tube seals I am seeing that come with the gasket? Where do those go?

[timsrv]

Some VC gaskets will come with the 3 rubber/metal grommets that seal the VC mounting studs/nuts. I suspect that's what you're seeing. In taking the VC off, the placement of these will become obvious. The spark plug tube seals are only held in by the spark plugs. I'm not sure you'll be getting these, but if you do, you change by removing the plugs, then the tubes will come out of the engine. Once out, the old o-rings will slide off and the new ones will slide on. Tim

[highwind]

got the 3 nuts off, I believe the seals are keeping the cover in place not sure how to get the seals out

[timsrv]

These rubber parts can get pretty hard & crusty. You'll need to pry them off. Most likely the rubber part will break, but then the remains can be dissected as required. I have a big pair of off-set dyke wire cutters I use on these. I put the sharp part of the jaws between the metal washer and the VC, then pinch and rock/pry until they pop-off. I'm sure there are other ways, but this way usually doesn't mark up or bend the VC. Tim

[Reducto]

If you're talking about the rubber/metal things under the nuts, I was able to get mine off by unscrewing them.

[highwind]

okay I found out the "seal's" lip seats itself over the valve cover. so I just took a flat head to them and pried it off.

these seals are rock hard and going to have to buy some new ones :/

[Alexleo]

I replaced the pcv and its grommet but the old one was so brittle I lost a bit of it in the engine. Am I going to have to remove the tip of the engine to fish it out?

[highwind]

I replaced the pcv and its grommet but the old one was so brittle I lost a bit of it in the engine. Am I going to have to remove the tip of the engine to fish it out?

no, it doesnt actually go into the engine. theres a layer of sheet metal in the valve cover that its caught in so you shouldnt have a problem

[Alexleo]

Thanks a bunch. Wasn't sure, was trying to pick it out and lost it to an opening on one side. Really didn't want to have to take the engine cover off!

[Alexleo]

I took the top of the 4y engine off any way out of curiosity. There's a baffle that protects the engine from any parts of the pcv that may fall in. It's got one orifice of about 2mm diameter around several narrow bends. Just in case any one does the same thing as me.

[highwind]

I took the top of the 4y engine off any way out of curiosity. There's a baffle that protects the engine from any parts of the pcv that may fall in. It's got one orifice of about 2mm diameter around several narrow bends. Just in case any one does the same thing as me.

since you have it off you might as well soak the valve cover in mineral spirits overnight to clean it

[brentlehr]

This should be pretty simple and it's self explanatory but I haven't seen a write up for valve cover gasket replacement. It's replacement time for me and I'm wondering if there's anything to look out for or parts I should go ahead and replace in the process. Any tips? Hope to tackle this while replacing my TPS.

[s_e_a_n_s]

I'm no expert, but just did this...

On my van ('87, 2wd, manual, no AC) it was fairly straight forward and could be done with just the 'hood' (driver's seat) up and didn't require removing the passenger seat and engine cover. It only required removing the PCV hose and one other. There was just enough room to get the valve cover out - rotated towards the passenger side, I believe, then forward.

Others report more trouble (http://www.toyotavantech.com/forum/showthread.php?2352-My-1986-Toyota-Van-LE-(Comprehensive-Tuneup)&highlight=valve+cover)

Things to watch for:


Be very careful with the valve cover bolts- they break easily. Don't over torque the nuts holding down the valve cover (7 ft/lbs? can't find the torque spec). Be wary when removing the nuts. Be careful when breaking the valve cover loose.
Valve cover can be stuck on pretty tight - mine was. (Decreasingly) careful application of a rubber mallet, and gentle prying was required. It needs to come up to clear the bolts, but sideways force was required to break the seal.
Valve cover gasket has a top and bottom. I should be fairly obvious, but pay attention to the orientation when installing (and of existing one on removal).
A good suggestion is to use gasket sealer in the corners. I didn't do this (out of ignorance/haste) and just used a little oil to help stick it in place for reassembly.
My (non-OEM) valve cover came with a set of rubber washers for the spark plug tubes, but not the rubber washers which go under the valve cover bolts.
Make sure you have clean sealing surfaces on the valve cover and head to give your new gasket a fighting chance.
Having a clean valve cover may bring smug satisfaction, as does re-discovering the obscured '4Y-E' sticker on top.


Check/Replace:


PCV valve, PCV valve grommet, and maybe hose. (as well as 'Ventilation hose #2 - also from valve cover to throttle body)
Rubber valve cover nut washers (for reference: Washer, Seal - 90210-09019 - probably no need for OEM part here - others may have an opinion).
While you're in the neighborhood, check you still have the seal on your oil filler cap. It helps keeps oil in (which shouldn't be a big issue if your PCV valve is working correctly) and keeps the oil cap from binding and being a PITA to remove.


My PCV grommet was so old and brittle it was a b*stard to remove the PCV valve (prybar required). The seal eventually just shattered and the bits had to be fished out of valve cover. Effectively cleaning out the broken PCV grommet pieces could only be done outside the van.

Use your judgement on replacing the PCV and vent hoses. They are not under any real pressure and easy to replace, so after very little consideration I decided my existing hoses were fine. They were not blocked, seemed to seal, and I was able to get them on/off without breaking them (not too brittle). I was afraid bulk hose would crease and close because of the tight corners (and vacuum). OEM hoses may still be available, but felt extravagant for my situation.

[hughdawgmmkay]

S_E_A_N_S, thanks so much for the write-up! I thought I was going crazy when I couldn't get the valve cover off, but your post helped me a ton! I just went out and used the rubber mallet on the sides a few times and broke the seal loose after reading!

Woulda been stuck without you!

[spacecruisers]

could you provide part numbers by chance?

[fuquan]

Greetings, TV fans:

The time has come for me to ask for advice from the community.

Let me boil it down:


Engine in my '88 TV was rebuilt about 25K ago.
Engine looses oil - more than normal.
There is no evidence of oil dripping on the ground.
Very rarely, I have blue smoke on startup.
No visible smoke coming out the tailpipe while driving, but I know this is difficult to assess. Must find a 2nd party to help answer this question.
Oil residue creeps up the valve cover from the vc gasket, and down from the vc gasket
Valve cover is on tight enough, in my opinion.
Oil residue is visible at the junction of the pcv valve and the valve cover.
Oil residue is visible at the junction of the pcv tube where it meets the intake manifold

Or this could be from the other hose ?, the one that comes from the front of the valve cover and enters the intake manifold above the nipple for the pcv hose.


I have a recollection of replacing both my valve cover gasket and pcv in this van, but this is my 3rd van so I could be mistaken.


Is this likely to be a simple pcv issue?
What steps can I take to diagnose/solve the problem?
I am about to buy a new pcv, pcv grommet, vc-gasket, and hoses to go from the valve cover to the intake.
Any input would be appreciated.
See attached pics.

52125213

[Ace MM]

I'd replace the valve cover too.
Easier to spot a leak after its cleaned up.

How do the plugs look?
Valve guide seals could be leaking.

[fuquan]

I'd replace the valve cover too.
Easier to spot a leak after its cleaned up.

How do the plugs look?
Valve guide seals could be leaking.

I think I'll just clean the valve cover with mineral spirits and paint the outside with high heat Rustoleum. I can't imagine anything being wrong with the cover, unless it's warped. I'll check for warpage.

Here are the plugs. I believe they have 20-25K miles on them. Could somebody with experience please read these plugs?

5217

[Burntboot]

I imagine Ace meant the valve cover gasket, the leak portrayed in the pic is a classic example.

The cover should survive but if you're going to paint it, better to have it off so you can do a decent job.
Besides, its easier to extract the bits of PCV grommet that fall into the baffle plate, with the cover off.
Just as important as the gasket, the washers that go under the nuts, when they're hard they'll unscrew like a nut (making cover removal much easier)
But they'll also let the nut bottom out without providing sufficient pressure to seal.
Change the tube gaskets and toss in a fresh set of plugs while you're there and hopefully call it done.

[fuquan]

I imagine Ace meant the valve cover gasket, the leak portrayed in the pic is a classic example.

The cover should survive but if you're going to paint it, better to have it off so you can do a decent job.
Besides, its easier to extract the bits of PCV grommet that fall into the baffle plate, with the cover off.
Just as important as the gasket, the washers that go under the nuts, when they're hard they'll unscrew like a nut (making cover removal much easier)
But they'll also let the nut bottom out without providing sufficient pressure to seal.
Change the tube gaskets and toss in a fresh set of plugs while you're there and hopefully call it done.

Thanks, BB & Ace:

This time around, I ordered a genuine Toyota gasket, pcv, grommet, washers, and hoses. I was using fuel line for my pvc-to-intake hose, which I have since learned is a no-no. Also I was using a non-OEM hose from the front-hole in the valve cover to the intake. Will also replace plugs and tube gaskets.

[Ace MM]

So those are the plugs from the rebuild?
They don't look all that bad. Not fouled with oil deposits.
Definitely replace them.




I imagine Ace meant the valve cover gasket, the leak portrayed in the pic is a classic example.
:brainfart:

[fuquan]

So those are the plugs from the rebuild?
They don't look all that bad. Not fouled with oil deposits.
Definitely replace them.

Yeah those plugs should be from the rebuild. Glad to hear they don't look bad. I'll replace them.

[blakebecker37130]

FYI,

My 89 had a loose/ cracked PCV hose. I would consume a quart of oil in less than 500 miles. After new hose was installed there was no more oil consumption issues. This is one of those issues that costs very little to fix and returns the desired results.

Best regards,

Blake

[fuquan]

FYI,

My 89 had a loose/ cracked PCV hose. I would consume a quart of oil in less than 500 miles. After new hose was installed there was no more oil consumption issues. This is one of those issues that costs very little to fix and returns the desired results.

Best regards,

Blake

That's reassuring. Here's hoping that's all there is to the oil loss, so that I can have a fun summer in the van :yes:. I will report back after I receive and install parts.

[fuquan]

Part replacement complete.
A few notes:

1. After comparing the new Toyota PCV (12204-15022), it became obvious that the old one was clogged, even though the old PCV did rattle to some degree.
1a. The Toyota PCV and grommet (90480-18001) fit into the valve cover much more securely than I recall with aftermarket PCV and grommet.
2. The Toyota valve cover gasket (11213-71020) fits SOOO much better than the aftermarket gasket. I remember struggling to keep the aftermarket gasket seated while I positioned the valve cover on the cylinder head. However, the Toyota gasket seats in the valve cover perfectly and it stays put.
3. The new Toyota hoses (12261-73021 & 12262-73010) that go from the valve cover to the intake are FAAAR superior to the auto-parts store tubing I was using. The fit is amazingly snug.
Next step is to take it out for a weekend (next :dance2:) and monitor the oil level :cnfsd:.

A lingering question I have, and have always had, is: How tight should the valve cover be? I did my best to tighten the three acorn nuts slowly and evenly, getting them "firm" (beyond "snug"), while taking care not to get them "overly tight".

5257

[Burntboot]

My factory manual makes it very clear.
"Install head cover"
No torque specs are listed anywhere.

Its always been my practice, to go just a little better than snug, keep an eye on it for a few days and if you notice any seepage, snug a little more.
You're description sounds about right.
OE parts are indeed the way to go, whenever the budget allows.

[Ace MM]

No torque specs are listed anywhere.

Its always been my practice, to go just a little better than snug, keep an eye on it for a few days and if you notice any seepage, snug a little more.
Spec is: goodNtite
Only needs a few ft/lbs, but the practice above is solid advice

[Mojoworkin]

I googled, searched, looked and looked. Then I bought the part so I would know exactly what I was looking for. No can find. Where is the PCV?

Reason I'm replacing: Van seems to be burning a lot of oil, so I'm going after the cheap possible causes first.
(Engine purrs, no obvious smoke,It's not in the coolant plugs looked OK, compression was 170, 170, 170, 150)

Thanks in advance!

[originalkwyjibo]

Pcv valve is in the top of the valve cover under the rear most hose. The design of the hose pretty much completely shrouds the valve. Be prepared for the hose and the grommet to disintegrate upon removal.

[blakebecker37130]

I had a similar issue. The hose to my PCV was cracked. From what I understand there needs to be vacuum pressure present inside the valve cover or the van will use a ton of oil. I was seeing a loss of a quart every 500 miles, with no burning symptoms. Once I replaced the hose and valve, the issue was resolved. Less than 15.00 if I remember correctly.

[Mojoworkin]

Thanks for the replies! I could not see the rear-most hose from the vantage of the seat-hatch.

I'll find out soon enough by myself, but do I have to pull the seats, etc, or is it reachable from one of those hatches on the rear? Regardless of answer, I may just take the time and cut myself a Hose of Death hatch anyway.

Blake: Did the PCV failure cause any issues other than oil? I have read that a bad PCV can cause rough idle, and this engine purrs pretty nicely.

Thanks again, friends.

[Mojoworkin]

UPDATE:

PCV is fine. It's an OEM and all metal. Makes the Beck-Arnley thing look like a piece of junk. Also, a quick test showed the new one did not hold vacuum, so... Yeah.

The interesting thing to note is that both the hose connected to the PCV to the intake(?) (throttle body? dunno what to call it) was cracked, as was another hose that connected the throttle body or whatever to a hard vacuum line. I am assuming the latter supplies vacuum to the "throttle body" and the former carries the vacuum to the valve cover.

In any case, both of these lines are pre-formed and rigid. LAPS says they can't find/get those parts and suggested straight hose. As long as there are no kinks and I can get a good seal, any downsides to this?


Thanks!

[blakebecker37130]

My van was running fine. I only discovered the issue after I kept getting bugged by the oil light on the dash. I used straight vacuum line to make the repair. The way I routed it as not to kink it was to take a piece of coat hanger, cut it and bend it to match the profile of the molded hose, overlay it on the straight replacement hose and apply halflap electrical tape to make the new hose assembly. It worked out great. I just sold that van, but I have no doubt the shade tree engineered hose will last a long time. Very similar process to wrapping brake and shifter cables under road bike handlebars, if you can visualize that?

Best regards,
Blake

[Mojoworkin]

Dig. I am still laughing at myself for totally not seeing the PCV. Turns out I could get to it no prob after pulling a few other hoses. Straight hose seems to be working fine. 7272

[Mojoworkin]

So... Son comes home, and I describe that while he was gone I discovered oil was low, how I did the PCV but let's do an oil change, get some extra oill to keep in the van and keep an eye on the level to see there are any changes. Son goes out to car, and since the seat is up, he checks the oil - which mysteriously is now at a normal level.

Whaaa? I had not added any oil after I did the PCV, thinking I'd do it another day before the son came home, but didn't. The van NEVER MOVED but we got two VERY DIFFERENT readings when checking oil. One time about halfway down, the second time right on the button. Both times the van had been sitting with plenty of time for oil to settle into crankcase.

Am I haunted?

[Burntboot]

I have seen a few vehicles over the years that were incredibly slow to drain back.

I would do a couple of back to back crank case flushes with good oil and filters and see if that takes care of things.

I have also seen one that "made" oil, but that was due to leaky injectors, leaking fuel into the crankcase.
But if that is the case, the oil will smell strongly of raw fuel.

[blakebecker37130]

Once you have ruled out other factors like leaking injectors, I would also recommend that the oil level is checked and confirmed by one person, if you have not already done this? This would remove factors from the result, such as dipstick not fully inserted, which side of the dipstick is being read ( if van is on uneven/in level surface).

[Mojoworkin]

I have personally confirmed the dipstick reading. (In other words, I was the dipstick doing the reading.)

Vehicle was level. Oil smells like oil.

Thanks to EVERYONE that contributed! I hope I can give back a little sometime soon.

Ron

[benjammin_all_my_life]

You'll need to remove some vacuum lines and things before you can remove the valve cover. These will likely be brittle and crack, so it would be wise to have new ones ready. Also there's the PCV valve & the rubber grommet in the valve cover the PCV valve sits in. That grommet usually crumbles when messed with, and is best removed/replaced while the valve cover is removed. See picture below for part numbers:

http://i8.photobucket.com/albums/a23/timsrv/TVT%20pics/Engine/valvecoverhoses.jpg

The grommet (Dorman part shown above) is available at almost any auto parts store and is usually hanging on the "HELP" rack. There are also the 3 metal/rubber washers that help seal the valve cover around the mounting studs. These might come with the valve cover gasket (depending on where you get), but if not ask for them and they will have them (these are very common and used on many Toyota engines). Tim

PS: I looked at your link and it looks to me like the gasket you purchased comes with the metal/rubber washers.


Hi Tim, was inspecting my newly acquired 87' rwd van earlier today to prepare for replacing my valve cover gasket when I noticed that a large bolt is missing from the engine block. It is directly to the right of the Valve cover. I don't have the manual for the van and am wondering if you know what this bolt could be for, and what the part number is. The bolt hole is filled with oil (as well as most of the engine surface). I apologize for the limited view of the bolt hole, you can see my flathead driver pointing to it in one of the photos. Thank you in advance!

[timsrv]

Nothing goes there. It's just a hole that's likely there to aid in the manufacturing process. Once the manufacturing is completed these have no practical use. All vans have these and it's nothing to worry about :). Tim

[MotoVlogMiller]

so ive recently replaced my valve cover gasket, I put in a new PCV. since, ive also also done the harmonic balancer that was leaking. im still getting a very small amount of oil on the lowest part of the transmission on the passenger side, im going to go take a look at the spark plug gaskets. my question is where did you guys buy the line that goes out of the PVC I couldnt find one anywhere. toyota told me they done make them. but since ive done that work it doesnt seem to be leaking much oil but after a 400mile trip I go from F to L so my guess is im also burning a lot. and I know the PCV can be an issue with that. its also been a little harder to start. so im a bit confused, I did use fuel like coming out of the PCV maybe thats my issue? ideas? symptoms are hard to start and burning oil, to me it sounds like a bad PCV but I just changed it...?

[Burntboot]

Oil consumption that is noticeably worse with highway driving, usually indicates an issue with stuck rings/worn cylinders causing excessive blow-by.
Continual chasing of oil leaks is an indication of excessive crank case pressure.
It also causes PCV systems to accumulate build-up of oily sludge, further compromising breathing.
Things usually go down hill from there.

One also needs to be careful with PCV valves, I have had (significant) trouble with A/M versions and will not use them anymore.
Nothing worse than beating your head against a wall for a couple of weeks only to find out its your "new" PCV at fault (BTDT)

Worth doing a couple of SeaFoam flushes first, then monitor consumption and proceed from there.
Even if you do compression and leak-down tests, you're still gonna want to try flushing, as the alternative is internal engine work.
If done correctly, a flush shouldn't cause any problems, now it may very well exacerbate existing conditions, but wont cause damage, in and of itself.
YMMV

[BelueJacques]

What is general consensus on which valve cover gasket to use?

Reading that others have not had great success with Felpro. OEM seems best but they are harder to obtain, more $ and don’t come with tube plug gaskets. Is it worth the extra time/$ for Toyota or has anyone been happy with an alternative?

[timsrv]

When it comes to valve cover gaskets I'm indifferent as to brand. I've even used the cheapest ones on rockauto.com (Beck Arnley 036-1292) and they also seem to hold up well. It's more of an o-ring than a gasket and once compressed they do a good job........as long as you're not under or over tightening. But yes, if you want the spark plug tube gaskets or the little metal/rubber valve cover washer/seals, you do need to purchase those separately. Tim