Valve gasket cover leaking/seeping
 

Hi,

I just purchased a 2000 ES300 with 40,000 km (25,000 miles). Previous owners were in their 90s I estimate. My first Lexus. Anyway, when my mechanic inspected it he noticed and showed me that oil had seeped out from around the valve gasket cover. I've read on this forum that this is a common issue with these cars. My question is it how urgent is it to get this repaired? Can I drive it for a while? I do plan to get it done but have spent enough money this week buying the car and new tires. My wallet could use a little break.

Thanks,

Brian in Ottawa Canada

As long as you keep the engine oil level correct you can drive it like that nearly indefinitely. You could try tightening down the nuts but be careful they are delicate and can snap off. I strongly recommend you replace the transmission oil.

Sound advice above.

I think the torque spec on the VC bolts is 13 ft/lbs. So you can tighten them, but with too much pressure you can in fact crack the valve cover on the corners. Likely, this won't matter as the one that leaks most often is the rear (less air flow, more heat, more down angle), and you can't get at the bolts w/o removing the intake system. So, run it to 100k when the timing belt and spark plugs are due, and replace the rear one then. The front can be done easily. Just live with the burnt oil smell on shut-down (that is oil dripping on the exhaust manifold), and top it up. It shouldn't really leak a lot; I think when I had a leaky rear gasket it was only like 1/2 qt extra consumption every 7.5k miles vs. afterwards (1/2 qt per 7.5k of "normal" usage even at 275k miles on the engine).

The spec on timing belt change is (I think) 7 years/100k miles. This is argued bitterly as to which to follow. I side with both - follow years if you live in a dry, hot climate that sucks life out of rubber - Arizona, the Middle East, bits of Down Under. Follow miles in temperate climes with humidity and mild summers. So where I you, I'd drive it to 100k and deal with gaskets then with plugs and timing belt.

The transmission on these is the most fragile of all ES's. The U140e has a known problem with an overloaded thrust bearing that can shatter. Fatal to the transmission, and as far as I can find, no rebuild upgrade that can prevent it from happening again. I would drain and fill it each 20k with Castrol Transmax HM. The reason for that particular fluid is that it is not only TIV compatible, but slightly thicker than normal DexIII/TIV (8.0cSt vs. ~7.2cST). Lubricant film strength is correlated to viscosity and this can nominally help with that weak bearing wear. This is just a shame because the 00-01 ES is the prettiest of all, with an engine as good as any, and unfortunately cursed with this flaw. If I could find a way to rebuilt the transmission to eliminate this, I'd snap up a clean, low mileage 00-01 ES300 as my next car in a heart beat.

Don't run the oil over-long; the 01 and earlier can sludge with abusive/negligent oil regimens. A really good 10w-30 synthetic can keep these running forever (I like Mobil 1 10w-30 High Mileage), and is good down to -20C without breaking a sweat and even lower. Don't buy the marketing and misinformation hype of thinner oils that protect less, unless you are routinely starting it up in winter after sitting outdoors overnight at -35C or lower.

Funny as I just replaced the front valve cover gasket on my 2004, hardest part was getting the spark plug seals out. It’s a relatively easy job if it’s just the front, so you may be able to tackle it yourself if you want but but the reae is a huge pain in the ass. Congrats on the low mileage ES by the way.

Thank you for the response to my initial question and even more for the other advice. I will keep an eye on the oil level and get the transmission fluid changed soon with the stuff Oro recommended or equivalent. I'll do the valve cover gasket at the same time as the timing belt. I appreciate where Oro landed on the timing belt timing debate. He sounds like he knows a thing or two but I'll do my due diligence and search this site for other views. The car is 18 years old. Although this is a cold climate, I believe that it spent most of its life in a garage. Not sure if that makes a difference.

As a new owner of a 2000 ES300, I'd welcome any other advice or links to important resources or forum posts.

Brian

All I can say is you’ll enjoy the car, between the 10 Lexus between my father and I ranging from 1992 to 2014, the 2001 ES300 was definitely one of the favorites and I definitely regretted selling it with 240,000 miles

If/when you decide to do the VC gaskets, stick two 5/16" washers with each VC bolt (36 total for 18 bolts). New bolts have a crush washer IIRC, but even those bottom out and eventually back out (ask me how many flopping valve covers I've seen). Spacing them out prevents this.

Honestly the design of the head covers is poor unless you do it perfectly and use OEM quality seals it will leak in short order. Possibly heresy to some but I've started running a bead of RTV all the way around the gaskets. Makes life harder when doing the job next time but it prevents leaks. You need to use a caulking gun unless you have nerves of steel and can run a perfect bead while squeezing the tube like a gorilla.

On timing belts and age, 8 years ago I bought my ES it had 56,000km on it the timing belt was mint I regret changing it. Do I think it would still have been fine 8 years later? Yep, but as mentioned climate plays a factor I would imagine in a locale with high heat most of the year the rubber would get crispy.

If you can find a used rear (RH side) cylinder head cover from a 2003+ ES (someone confirm years) it's a good investment Lexus updated the baffle design which greatly reduces the potential of oil sludge.

After replacing my front valve cover gasket, I was not looking forward to doing the rear. However, I was able to access the lower rear VC bolts going under the car (on jack-stands) and slipping my hand up by the firewall. After snugging them down there was a significant reduction of oil seeping out.

2002+ are the revised rear covers as he suggests.

The trick I finally learned about good gasket repairs are a) little bit of gasket dressing like Permatex #3, and b) torquing multiple times over a day or more.

The gasket will “take a set” after compression. If you let it sit overnight and check them again, possibly 1/2 of the bolts will be only finger tight. So I then re-torque them. Usually that is all it takes, but as another step I check them a third time after the engine or transmission has been run to temperature and cooled.

The other thing I would do with a transmission is add some Lubegard red to it (and an ounce of that in the ps system). The chemistry of it is real and can help protect the weak points.

Thanks, I'm gonna keep an eye out at my local junk yard.
Is that the same thing as Lubegard 60902? The form-a-gasket is a good idea more convenient than trying to smear it on from a tube.

PLEASE hear me out. Congrats on the GREAT purchase. Change all the fluids with toyota genuine as 18 years does a lot to the originals.

The valve cover gasket leaks because its dried out. as stated above, there is a TINY amount of torque holding those valve covers down, by Toyota design - that is a LOT of engineering. torquing them down more is not the solution. replace the gasket. the biggest obstacle is the bolts behind the plenum and many have changed them to stud/nut arrangements for easier future access. The other problem will be the massive wire harness that runs through the middle of the rear valve cover gasket that was flexible in 2000 but NOT anymore.


If we were having this chat at 80,000 miles i would say throw new sparkplugs in there while you are at it, but yours have 75000 left in them. Instead, do the stud/nut mod to the plenum brackets and enjoy easier access in a few years when its time to do the spark plugs.

You could drive the car like this forever, but as it gets worse, you'll get a terrible smell as oil drips down onto the exhaust manifold. that first red light after exiting the freeway is going to make you want to vomit.


There are videos on YouTube, and many people here that are willing to help

Thanks for the advice folks. Both helpful and reassuring. Given that I'm not too mechanically inclined, I can't judge the semi-conflicting advice about the valve cover gasket (caulking? torquing? washers?). There seems to be a clear consensus on fluids, however, which I'll do soonest. I paid $4000 Canadian ($3220 US) for the 2000 ES with 40,000 km (25,000 miles). I hope it proves to be a good decision.

Brian

Got any pictures of your car?

$4000 for that car you stole it. I've been offered $10,000 for mine.