Rokas

On this very forum somewhere I had read that when a valve cover gasket gets old and starts leaking, the bolts are also loose by that time meaning they need to be re-tightened.

Now, an employee at Advance Auto parts confused me so I come here. He told me to tighten them just a little. On the forum here, where I cannot find the post, says to tighten them to original torque levels but I understand the guy may be seeing the gasket may... Crack? Is that why?

My question really is just how much do I tighten these to potentially stop my car from leaking oil until I can take care of it better? I tightened them to where they're very snug but I never put a lot of force on then. Some were pretty loose. Suggestions please. Tighten them hand tight maybe?

I should say that the car went from dropping a quart a day to a quart every two and a half days since I tightened the bolts a little. I just don't want to make it worse. Thanks guys.

Rokas

Oh and no I didn't break that cover... Someone not only broke it but cut a hole in it cause they can't do wires properly...

oldskewel

iTrader: (1)

The initial torque spec was based on a new, flexible gasket. Over the years, heat cycles and age have made that gasket harden and shrink, and maybe caused the bolts to back out slightly since the torque value is so low. So now, the concern is that when you apply torque, the hardened gasket may not respond like a new one would, and you'd get concentrated stress points rather than uniform sealing.

But at this point, I would definitely not back them out. And I'd say that one quart every 2.5 days is an improvement, but still not tolerable, so I would tighten them some more. If you want to be careful, go a little at a time and see how the leak progresses. Worst case is that you'll need to take things apart and actually replace the gaskets, which is not such a bad thing. And you will know that you tried your best to make the easy fix work.

Rokas

That's very good advice. Thank you. I suppose I will let you guys know what happens.

Tightening those bolts is easy but how hard is it really to replace those gaskets?

Rokas

Is there something I can spray them with (the gaskets) to make them less brittle as I do this?

billydpowe

iTrader: (1)

no, not really, oldskewel gave you all the real advice you will need.... my advice would be replace them... think pride of ownership...

Legender

Replacing them is the way to go. They are old, hard, brittle and have lost their ability to seal. The only real solution is to replace the gaskets along with:
spark plug tube seals
PCV grommet
PCV valve
PCV hose
Might as well do the plugs while you're there....

A quart a day... I hope you're doing about a thousand miles a day if that's the case... that's a lot of oil.

Michael88

These rubber gaskets shrink! There is no way that I could manage to fit a torque wrench in there to torque to a spec value. I tightened them to 20 pounds by experience and feel of the wrench. In other words, tighten until you get them tight and then not a quarter turn more. DO not overtoghten these bolts you will be sorry when they break off or strip an aluminum head. You will be drilling and tapping. I have done a lot of valve cover gaskets and these are by far the hardest I've ever done. I wish I would have tried tightening them first.

dicer

This is one area the Lexus bunch goofed.

OldLs400

The valve cover gaskets are fairly difficult to change simply because the bolts are difficult to access and removing the drivers' side cover requires a lot of wiggling around. You could remove the dipstick tubes, but that's complicated in itself. If you don't remove the dipstick tubes, be prepared to carefully wiggle a valve cover through a maze of wiring harnesses.

To give you an idea of how hard it is to reach some of the bolts: I went to Harbor Freight and purchased a wobble socket extension set. I ended up having to connect 3 or 4 wobble socket extensions just to reach some of the valve cover bolts. For one bolt, I remember connecting a few wobble socket extensions along with a flexible socket extension just to loosen it!

If you decide to replace the spark plug tube gaskets, get a 32mm socket. You'll need the 32mm later if you plan on doing suspension work. The 32mm socket is useful for pressing/hammering in the socket plug tube gaskets.

Also, you might want to get the biggest pair of vise grips you can find. I needed like a 3 foot long vise grip to remove the PCV valve; it probably hadn't been touched ever since it rolled off the line in Tahara in 1997.

Again, it's not really a difficult job, and I don't want to scare you from doing it. I did the job successfully and the only thing I could do before replacing the valve cover gaskets was change the oil on my car. It just takes patience. Prepare to spend a weekend since you'll probably be running around gathering parts; I had to run out and get the socket extension set because everything was in the way.

Perhaps you could try a bottle of stop leak before doing the valve cover gaskets?

PS: be careful of how you put the cover back on. The first few times I put the cover back on, I didn't exactly secure a few bolts. Some bolts were in, while others were misaligned and loose. I didn't realize until I felt a puddle of oil by my feet--the car was literally pissing oil on my garage floor! I reckon that I lost about 2 liters of oil before I noticed!!

Gavin8399

you dont, you replace the gasket, probably a 25 dollar part.

Losiracer2

I vote to replace the gasket. If you have a quart a day gasket, tightening them isn't going to help much. The gasket is completely blown.

Toyota doesn't use a traditional gasket from the factory, they use a FIPG, basically a very high quality silicone you see in the tubes done by a machine. That's why they've lasted over 20 years without leaking. My 97 has 292k and is just seeping, so I've opted to leave them for now, until I actually see smoking or drops on the ground. I have some traditional Fel-Pro ones to replace them with along with the tube seals when the time comes, but I bought those over 2.5 years ago and have still been waiting for the leak to get worse, which it hasn't in over 40k miles.

Rokas

I agree with all of the advice completely.

My problem is that me and my wife are barely surviving. My health is going down the drain so I've been earning like $100 a week which is nothing. We're trying to move and having some real problems doing it. At this point, sometimes we have to choose between gas or cigarettes.

Anyway, I'm going to tighten them a little more today, pray it doesn't get worse, and see what happens.

I can do the job eventually but I also have to change the timing belt soon so yeah... Gonna be a month I hope and no longer. :/

Whoever said the thing about pride, yes I agree. They're getting changed out as soon as I can do it.

Sometimes I'll sacrifice food to get a bulb or something for my car.

Question: Someone brought up the stop leak. Is it worth trying? I've tried similar products without much results. Don't they work by hydrating the rubber gaskets? Anyway, let me know it won't hurt my car and I'll try it if it's still dripping after this last tightening.

I appreciate all of you very much.

OldLs400

I doubt an oil stop leak will hurt if you get a reputable brand. I poured an entire bottle of bars triple stop leak down my ls400 and I drove it from FL to NY with 0 issues. I didn't even have a leak; I had just changed the valve cover gaskets. I just dumped it into the engine for preventative maintenance and because it was only a few dollars at Walmart.

I've used bars stop leak products in my radiator and power steering and they seem to be decent products. At the very least, they haven't looked anything yet. The coolant stop leak actually worked and I paid less than 2 dollars for that fix. The PS I'm not sure because I didn't put in the whole bottle, and the PS system kept leaking.

Give a stop leak a try and let us know. Good luck. Perhaps try avoiding the Lucas products, they seem to be nothing except an oil thickener. Many of the stop leak products have money back guarantees anyway.

Also, if it makes you feel any better, I put in at least 4 different stop leak products in my Power Steering system after replacing my alternator because I did not need another alternator to be destroyed by a PS leak. I put in full bottles of SuperTech ATF Stop Leak, TransX, Prestone ATF+Stop Leak, and Bars 2-in-1 Stop Leak, as well as fresh Valvoline MaxLife ATF, which has seal conditioners.

My power steering system hasn't died yet! (And I think it stopped leaking)

oldskewel

iTrader: (1)

I would not try the stop leak. You probably have too big of a gap so it would not help much, and might cause problems elsewhere.

I hear you on the budget timing. I always try to give facts and suggestions, but I realize different people will come to different conclusions based on their situations. Sometimes you kick the can down the road and keep doing it.

One thing to be concerned with on the gasket replacement is that it will probably not just be the gaskets getting replaced. At a minimum, once you're in there you'll want to do spark plug seals, bolt grommets or whatever they're called ... AND THEN ... everything else that cracks and snaps while disassembling. vacuum lines, etc. Good chance a lot of stuff in there is brittle and happy until it gets touched, then it becomes a problem.

What year is your LS400? I might have an extra set of VCGs for you.