Toyota Avalon 2000 Valve Cover Gaskets


#1

Hi everyone. I had an oil change at the Toyota dealer today (not my usual spot), and they cited front and rear valve cover gaskets for the engine were leaking into the manifold. I have not noticed any oil below the car. Estimated repair at the dealer 644.08. The car has 148,000 miles on it. I have read this is a common issue for some Toyota cars in this year range. Is this a necessary repair? I did notice the oil was low (via dipstick) once around 146,000 miles and topped it off with a quart, but never have had that happen before. Previous oil changes mostly at one or two Pep Boys locations, and this was never mentioned. Would appreciate any advice. Thanks!


#2

When did you last have your timing belt changed? It should be done every 6 years or 90kmiles so you should be coming up on your third belt change. The valve cover gaskets should be changed at that time as most of the labor is covered by the belt changed.

If you are not losing a lot of oil, I would not rush into changing the gaskets. Also I would strongly recommend that you get several quotes from independent mechanics and from several dealers if you have several of them in our area. The quote you got seems way high to me.

Do keep an eye on your oil level though.


#3

The back one requires removing part of the intake manifold, not included with a timing belt. I’d look for a good independent shop (click on “mechanics files”) and get another estimate. I did it when I started smelling the burnt oil on the exhaust manifold.


#4

If it isn’t leaking onto the exhaust manifold and smoking and the loss isn’t great enough to cause concerns about the amount used, just watch the usage amount and drive on. It is not at all uncommon for 16 year old engines to exhibit some oil seepage through the valvecover gaskets and it’s meaningless as long as the engine doesn’t run low on oil. It’s caused by normal pressure from the crankcase, which is open to the spaces under the valvecovers, slowly forcing oil past long-compressed gaskets that no longer hold the pressure as well as they used to.

Contrary to popular belief, engines do not die from oil usage or leakage. They die because the oil is allowed to run too low. The way the system works, the pump draws oil from the pool in the oil pan and pushes it through the necessary passages under pressure. Once it lubricates the rocker arm assembly, it just runs into open “galleys” and drips back into the pan through open return passages. As long as the pan doesn’t run low, the lubrication system works normally.

This “needs new valvecover gaskets”, a rarely necessary repair, is a big moneymaker for dealer shops, and these past ten years or so dealers seem to be prone to find a revenue enhancer on every engine they see. “Needs a new oilpan gasket” is another of the more popular unnecessary revenue enhancers these days, so don’t fall for that one either.

If a dealer shop explains gasket seepage to a customer and offers to replace the gasket if the customer would like, I’d consider it an honest suggestion. But they don’t, they make it sound like a necessary repair, and it pisses me off every time I read it. Sorry. This one is a pet peeve of mine.


#5

@keith

On OP’s engine, it is NOT necessary to remove the valve covers to do the timing belt job

So there’s no money to be saved if you combine the valve cover gaskets with the timing belt job :frowning:


#6

The reply from “the same mountainbike” is worded perfectly.

If this were my 17 year old car and the oil wasn’t leaking enough to bother me (e.g. constant oil smell or excessive dripping on the ground), then I’d simply check it frequently and add oil as needed.

Your engine is apparently very far from worrying about excessive oil leaking from the valve cover gaskets.


#7

@db4690 I stand corrected. But I do stand by my statement and agree with MountainBike that I would not rush into this. One quart of oil between oil changes does not justify spending over $600 for gaskets. No ROI (return on investment) there. But do check the oil level frequently, like when filling the gas and you have nothing else to do.


#8

@keith

I’m just making a comment about the valve cover gaskets

I also agree that it’s not worth the effort and expense, at this time


#9

I wouldn’t worry about it too much. If you’re leaking onto the driveway or smelling it burn, then you might want to replace them, but as you described it, I would leave it alone. Try using a high-mileage oil for 2-3 times, then re-evaluate.


#10

Thanks everyone for your input. I appreciate it.


#11
front and rear valve cover gaskets for the engine were leaking into the manifold.

I think what’s actually happening is oil is leaking onto the manifold. Not into.

If allowed to continue this can create a bit of a mess and some odors & smoke. If the oil gets on the timing belt, it could damage that belt too. Or cause it to jump valve timing, which isn’t a good thing.

On the other hand, sometimes the dealer shops are instructed to be pretty stringent about pointing out every little problem to the customers. Either – the optimist might say – they are just trying to be as helpful as they can possibly be, or – the cynic might say – they are trying to generate some add’l revenue from their service dept. Who knows which it is in your case?

To find out, suggest you take your car to an inde mechanic shop for a second opinion. The shop you’d take it if you needed the timing belt or starter motor replaced, say. Normally you wouldn’t use a dealership to replace a timing belt on a 2000 model since the dealership shops are a little more expensive and tooled-up to service the newer models. Your inde shop may suggest to just monitor the situation and measure the amount of oil you need to keep it topped off between changes.

Some background might be helpful. My car is an early 90’s Corolla 4 banger which I’ve owned since new and I’ve had to replace or rejuvenate the valve cover gaskets three or four times over the 20+ years due to small oil leaks. In some cases I’ve been able to stop the leak by re-torqueing (to spec only) the valve cover bolts, but not usually. More often after I remove the valve cover the problem isn’t the gasket per se, but near where the camshaft seals are, the gasket doesn’t cover that area very well. So what the manual says to do is apply a little rtv sealant, and that rtv sealant tends to break down more quickly than the gasket. So I just clean and reapply the rtv sealant at those critical spots and that stops the leak, no need to replace the gasket. But removing the valve cover on my Corolla is a pretty simple job, just three easily accessible bolts and it pops right off. Even using a new gasket set and a $100 per hour mechanic doing the valve cover replacement job I can’t imagine it would cost over $200. Apparently this isn’t the case with your Avalon, and it is a pretty pricy job.


#12

Thanks for the input. My original plan was to monitor the oil levels for awhile as I just had an oil change, however I am a bit concerned about the risk of fire from the oil on the manifold. How realistic a possibility is this? If I don’t smell any oil burning, am I in the clear? The timing belt was changed previously, but never the valve gaskets.


#13

Motor oil has a flash point around 420 degrees (F). For comparison, diesel fuel around 120, gasoline -45. I’d guess a fire in that situation you describe is unlikely, but not impossible.


#14

Very low probability. You couldn’t even light oil with a match.
Oil needs to be vaporized and subjected to high heat to ignite. Even then it doesn’t burn well, which is why it leaves a mess of carbon and “oil ash” everywhere. Gas evaporates readily into the air. Oil just sits there and makes a mess. I guess you could say that gasoline self-vaporizes and oil doesn’t.

The process of combustion is the hydrocarbon molecules separating when subjected to heat energy (activity) and bonding to oxygen atoms. Gas molecules surround themselves with oxygen as they evaporate, oil simply doesn’t evaporate.

Oil CAN burn, albeit poorly, if sprayed and subjected to high heat, or if subjected to high enough heat to cause it to evaporate (boil off) wherein it becomes vapor, but that isn’t the environment your manifold subjects it to.

HOWEVER, if having the valve cover gaskets helps you sleep better, by all means go for it. Peace of mind has real value too.


#15

OK, I have a 2000 toyota avalon with 218000 miles. I just checked my oil and it was more than a quart low (this is not typical), and I have been smelling burnt oil in cabin usually just after startup when defrost especially has been cranked in winter. I susepect that it is the rear valve cover gasket. The smell usually doesn’t last too long, but is there any fix you recommend vs changing the rear valve cover gasket since most seem to say just check the oil and don’t worry about the leak or since I do smell it in cabin, do I need to replace it.
Thanks.


#16

Only other option would be to try a ‘high miles’ oil, one that swells seals and gaskets. I’d be surprised if it works, but it’d be worth a try. And keep checking that oil!