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?

[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.../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:



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/s...ht=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!