Valve Cover Gasket Change?easy Diy? Need Some Info.

[pete rock]

hi sorry for all the questions guys but i love the info im getting on here its pretty amazing and helping me out greatly in getting to know my es300 as good as i possibly can.ok now my question is i know that a common problem on the es300's are valve cover gaskets.i met a girl at a dealership thatw as selling an es300 that told me she did the job herself.my question is how easy of a DIY is this?and would it hurt if i did change my valve cover gasket just to be on the safe side and put a brand new one in?anyone done this themselves??please any and all info is much appreciated

[mdpresco]

I changed my '98 ES330 valve cover gaskets this weekend. I have worked on cars and equipment for many years and found a few surprises that I have not seen in the forums. On a scale of 1 to 10, for me it was a 6. It is not complex like an automatic transmission but you better set aside a day to do it. Here are a few hints if you choose to do it.

1) REMOVE the battery terminal.

1.1) Keep sand and debris out of the engine. Use compressed air to blow away from the valve covers and the plenum BEFORE removing them.

2) Mark the brackets with a Sharpie and remove the hood. Get a friend, or two, to help you. Don't scratch the paint! This makes everything more accessible. Note the bolts are not identical.

3) Use the Sharpie to mark the hoses and connections of those hoses you have to remove. Mark them as you remove them!

4) Do the front bank first. This will require hoses to be unplugged as necessary. The hose assembly if front of the plenum is held to the engine by bolts. This will lay over to the passenger side and get it out of the way.

5) The spark plug seals have tabs on the inside of the valve cover that "keep" them in place. I used pliers to gently bend the tabs back. Now you have to get the seals out. The spark plug seals are pressed into the valve cover and will take some ingenuity to remove. Maybe someone here has a easy way to do it. I carefully folded some of the seal over with a small screw driver and punch. Then, using a large screw driver, drive it out from the top, hitting on the folded area. Installing the valve cover seal and valve cover is elementary.

To do the rear bank, here are a few tips.

1) Unplug the EGR sensor and Remove the throttle body, not the cables. You may have to use some string to keep it out of the way.

2) Two brackets are bolted to the backside of the plenum.

3) Remove the EGR tube that bolts to the cast part. You will not be able to see the lower nuts. Don't drop them. This will help to get the valve cover off.

4) Cover the plenum openings. Free the rear O2 sensor connector from the bracket and unplug the sensor. Its wires are in the wiring harness on the valve cover.

5) The wiring harness that runs across the valve cover is a pain. I removed two nuts on the back (driver's side) of the engine (under the throttle body and center engine) and unclipped it on the passenger side. This, and the EGR tube removed allow the valve cover to clear the cam gears. Keep working gently to clear the obstacles to removing the valve cover.

During reassembly,

6) Before the plenum is tightened down, install the two bracket bolts on the plenum - finger loose. Torque the plenum, then tighten the bracket bolts.

7) Go slow and make sure all hoses go back on their marks and all connectors are plugged in.

Tools -

Retrieval tool to get those things you drop behind the engine

Torque wrench (32 ft-lbs) for the 2 - 14MM nuts and 2 - 8MM socket head cap screws on the plenum.

This by no means covers everything. Be methodical to the point of writing things down and/or taking pictures.

Good luck! If you are successful, go out to eat with the $400 you saved :D

[rg1]

During reassembly,

6) Before the plenum is tightened down, install the two bracket bolts on the plenum - finger loose. Torque the plenum, then tighten the bracket bolts.

7) Go slow and make sure all hoses go back on their marks and all connectors are plugged in.

Tools -

Retrieval tool to get those things you drop behind the engine

Torque wrench (32 ft-lbs) for the 2 - 14MM nuts and 2 - 8MM socket head cap screws on the plenum.

This by no means covers everything. Be methodical to the point of writing things down and/or taking pictures.

Good luck! If you are successful, go out to eat with the $400 you saved :D

Thanks for the encouragement...may try to tackle this one after done with IACV cleaning.

[homemechanic]

don't forget to change the spark plug tube gaskets also. buy the tube gaskets from the dealership for like $2 each.

the non-OEM tube gaskets are hard and difficult to put into the valve cover. the OEM tube gaskets are soft.

[motoroil]

^^^^^yes. Get the OEM tube gaskets at your toyota dealer as if for a camry. Aftermarket ones suck, and you'll probably scratch/dent your valve cover trying to hammer aftermarket ones in, OEM ones slip right in.

I have a '93 and did the vcg job, not too bad, front is easy as cake, the rear is a bit more difficult as you have to remove a fair chunk of components to get to it, and its an awkward angle for installation, so be careful when reinstalling the vc with the new gasket, it likes to move on you b/c of the odd angle. Some put a dab of gasketmaker at the rear of the valve cover in the groove to keep the gasket in place on reinstallation. So long as you use only a tiny dab, it won't cause any problems or leaks later on. (normally you don't use gasket maker when replacing a rubber gasket except for where the service manual instructs).

[capnfred]

I too just did a cyl. head cover gasket replacement, unfortunately I did not know about the OEM spark plug seals, and used ones from AZ, had to tap them in, but not too tricky, there are lots of things to take off, fortunately all the hoses are pretty self explanatory, as long as you dont take off both ends. I removed the throttle valve, left the IAC and EGR valve attached to the plenum, disconnected all the wires and hoses from the IACV/cold start end. Removed the support brackets, and EGR pipe, then removed the air intake chamber. Removed the Emisson control valve assy, be very careful on older cars as the plastic is very brittle, I used a piece of string to hold it out of the way. Removed the connectors from the injectors on and the 135 bank, undid the two bolts holding the wiring harness in place, removed the dogbone, and support bracket, gently lifted the harness until it would clear the two studs, then pulled toward the front of the car, held it in place with two pieces of string. Now the back bolts could be accessed with an extension and universal. I replaced the washers under the bolt heads for cover bolts with faucet washers from the hardware store.... much less expensive than the ones from the autoparts place. while I had the cover off I resealed the 1/2 moon inserts on the head, replaced the gasket and sp seals. Torqued the bolts to 4 1/2 ft/lbs, started in the center and worked my way around... crossing front to back, did this in three passes. Put everthing back together, started the engine and checked for leaks. I forgot, removed the plug wires.... replaced the plugs, wires, rotor and cap... very easy to do with intake assy removed. Not counting gofer time took about 3 hours total. Most of the time was spent cleaning the covers and replacing the sp seals. Mine were soooo hard that they were like hard plastic and just fell out. The most difficult part was getting to the back bolts to torque them....aslo there is a clamp on the hose to the hydraulic fan hose that attaches to the plenum. Not difficult, but very aggravating getting the interferences out of the way to do the work. I did not have to deal with the TV cable to the tranny as it has not been connected yet, but the easy way is to remove the two 10mm bolts that hold the actuator to the throttle valve, or just remove the two cables, the one from the cruise control just lifts out, the one for the TV has two nuts that clamp it to the assy. If you do loosen these nuts mark them so you can get the TV cable properly adjusted when you re-assemble everything. Good Luck...

Capn

capn

[SupraMan]

Thanks to all who posted on this topic, just did front vc gasket at 156k miles and will do rear soon. The rear has been a very slow leaker for the 60k miles I had it, just tolerated it until the front recently started weeping. Did get the sp seals at Toyota @$10/3 ... like previously stated, they just cracked in 2 pieces when removed. A breeze to do the front vcg; got courage to tackle rear now, I'll save $$$ and get the satisfaction of fixing it myself.

For a really nice pictorial on the 1MZ engine vcg removal, check out http://www.wjowsa.com/?p=30. Great stuff, online is sometime so much better than what's in repair manual print!

Did notice a little dried up sludge build up in the upper corner of the vc, probably just a nasty leftover from the slacker previous owner who liked Jiffy Lube service. I thought my post-purchase 2x Seafoam cleaner treatments and full synthetic oil use subsequent would preclude any deposits ... guess that crusty stuff in the upper corner didn't get splashed enough with the cleaner during the flushes. My concern is probably more overreaction to a normal situation, these engines are noted for sludging issues especially with dino lube. I'm just concerned that this may be indicative of much more hidden sludging, any thoughts on this?