msekanha

what's going y'all? newbie to these forums.. i'm sure you all get oil leak questions all the time, but hopefully me being as detailed as possible, could possibly point me in the right direction.
anyway, I have a '97 Lexus Es300 170k with a very minor oil leak. It's not a serious leak,
but it's starting to get all over my power steering belt and making ugly spots in my driveway. The whole front of the motor is wet with oil, so i'm not sure exactly where the leak is coming from. I don't think it's coming from the oil pan, considering the power steering pump is soaked and dripping with oil (positive its not power steering fluid). There seems to be more traces of oil on the bottom of the rear manifold too. Thinking it may be a seal behind the timing cover, i pulled off the upper cover just to find the timing belt and pulleys bone dry and free of oil. I've attached a picture of the leak and hopefully someone could give me a general idea where to look. The rear manifold is circled in white. Any ideas? anyone? any help is appreciated!

MikeLex

Your rear valve cover gasket needs replacement. Very common issue, but unless you are mechanically inclined, it's not a DIY.

PFB

Most likely it's your rear valve cover gasket. Put some UV leak detector in the oil, and you'll find the source of the leak quickly and easily.

Make ure however to thoroughly clean the engine first from any traces of the oil that alreay leaked out.

smee

Had my Rear Valve Cover Gasket replaced on my '95 ES300 recently too. Big job, my mechanic did it for me.

Hayk

iTrader: (1)

I also have my money on the rear valve cover. It's a pain in the *** to say the least.

msekanha

wow you guys reply quickly, nice!
I had a hunch it was the rear valve cover gasket also.
I just wanted you guys to confirm that before I pulled off
the intake plenum. So i'm going to have a fun weekend lol.
I'm mechanically inclined, however i've never done a rear
valve gasket job on this motor. So any tips while i'm doing this repair?
oh yeah, should i use gasket sealer with the new gasket?

OceanView

I have a similiar problem and want to DIY it myself but I am a bit hesitant as it will be a lot of work.
If your gonna do it yourself, would you consider posting a DIY thread on this?
It would help a lot of us out that also want to do this.

Thanks and good luck!

Hayk

iTrader: (1)

Since you're doing the back cover, it would make sense to do the front as well. Get all your parts from Lexus before you start.

You will need 16 new bolts because the crush washers cannot be replaced without replacing the bolts. Part # for the bolts w/ washers is: 90080-10288 (MSRP $1.75)

You will also need 6 spark plug hole grommets (they are tricky to replace). To get them out, you will have to unbend the little tabs that hold them in place. Then freeze the new gaskets in your refrigerator, heat up the valve cover holes with a hair dryer and grease em up. That should make slipping them in a lot easier. I also used a large socket and a mallet to tap them into place.

Here are two excellent sources for the valve cover job that I used as references this past summer.

1. Toyota Avalon/Camry step by step photo gallery.
http://www.wjowsa.com/carstuff/toyot...lve-cover-job/

2. Spark Plug Hole Grommet Replacement
http://www.toyotanation.com/forum/10...ent-1mzfe.html

I would also recommend getting a new PCV Valve and Grommet, it fits into the rear valve cover from the passenger(right) side.
Valve Part #: 12204-20020 (MSRP $8.25)
Grommet Part #: 12480-18001 (MSRP $5.09)

Finally, think about replacing your spark plug wires(if your car has them) and spark plugs, since you are already there. These do not need to come from the dealer, I bought my Denso spark plugs on Amazon and the NGK wires from AutohausAZ.

About the sealant, you will need to apply it in six spots for each cover. Two spots around the half circle and four spots on the seams on the opposite side. It will make more sense once you remove the covers.

There is just one more thing I forgot to mention. The 1MZ-FE engine has three coolant hoses (an unusual design). There are two that you can see (upper and lower), and then there is one small one underneath the main intake manifold (underneath the plenum). Since your car is a year older than mine, I highly recommend that you replace it at this time as well. Part #: 16261-20010 (MSRP: $17.85)

I chose to replace my intake manifold-to-head gaskets, but you don't have to. My old ones looked good enough to be reused. I also replaced the intake plenum-to-intake manifold gasket, it was splitting and looked fairly fragile. Part # for that one is: 17176-62030 (MSRP $10.05)

Finally, about the "unusual" tools that you will need. A 5/16" or an 8mm allen key/socket is used for the two front intake plenum bolts. And a Torx E6 is needed to remove the two bolts holding the wiring harness to the front valve cover.

If you have any questions, don't hesitate to PM me.

msekanha

so i just finished my valve cover gaskets yesterday and what a f%#*^$@ pain in the a$$ it was! never want to do that again lol. I couldn't wait for the new valve cover bolts to come in, so I just used some extra washers for now.. and despite turning my hands into swiss cheese and tearing out bank 1 02 sensor during the process, it doesn't leak anymore! Well... My oil pan is a different story, so i'll do that gasket this weekend. Does anyone know the torque specs to the oil pan?

msekanha

oh btw, thanks for the help everyone. it's greatly appreciated.
My driveway thanks you too lol

Hayk

iTrader: (1)

Great job! That's exactly how I felt once I was done with mine. How much of what I suggested did you do?

Hold off on replacing the oil pan gasket. I thought mine was leaking as well, but it was actually just the build up from all the previous oil filter changes. Because of such a poor design, everytime you remove the filter canister, some oil spills on the front of the engine and finds its way down to the back of the oil pan. Get some Simple Green, raise the car up and wash it all off. It worked wonders for me, and saved me money and a lot of frustration in the process.

msekanha

oh i've used all of your suggestions with the exception of the bolts and coolant hose.
Autopart stores didn't have those two items in stock and this was the only weekend
i could do do it. changed pcv valves, grommits, plugs n wires...
I gave my motor a good clean down with engine degreaser and a power wash,
but still seeing one very small drop on the passenger frame... hmm ill wait and see
what happens. but your suggestions were very informative and helpful. thanks again!