Valve Cover gasket leak? (9 Viewers)

[TenderWarrior]

Hey guys,

I have attached a few photos of my valve covers to try and show what little leak or residue there is. If you can make out what I’m showing, is there any concern that the valve is leaking? Pictures aren’t that great and are only of passenger side. Driver side appears dry.

There is some wet residue around the valve cover edge and looks like older oil stains on the exhaust manifold covers. Only appears on the passenger side.

This is on a 2004 LC and has 230k on it. The valve cover gaskets have not been replaced before.

I have found this thread for how to replace them and looks very doable. Valve cover gasket tips

 

[gungriffin]

Have you tried re torquing the bolts yet? I had a small valve cover leak that seem to have been resolved with a re torque of the valve cover bolts that 2001LC did when he swapped my spark plugs.


From @2001LC

Plugs and Coils

I just installed new Denso plugs and coils, 2000 LC w/197k. I've had a few aftermarket coils fail and wanted to get a complete new set of Denso's in there. I was surprised how goo-ed up some of the plugs were (especially 6, plugs are pictured 1-8 left to right, coils are not in order)...

forum.ih8mud.com

Yes INCH LB. 53IN-lbf, which is ~4.4LB-lbf. I use my little 1/4" torque wrench when spec is in low range, seems more accurate. Sometimes these head cover bolts are a bit frozen up. It may take a little more torque at first to get started turning. Then they'll usually turn 1/4 to 1/2 a turn to reach 53IN-lbf. I work in a crisis cross pattern (upper than lower bolts). I then come back around for a second pass.

Every 4.7 2UZ I've re-torqued these head cover bolts on, needed at least a 1/4 turn. Seems we get shrinkage over time between the rubber washer under bolt and the rubber gasket under head cover. We've seen very good results in stopping head cover leaks doing this. I do as a PM.

For those in rust belt, good luck. These bolts can be frozen in. So go easy! They are very small bolts and can break easy.

 

[TenderWarrior]

I have not tried that yet. I’ll give it a shot. I probably will clean up what’s there too and see if it’s actually still leaking.

Part of me wants to just go ahead and replace them anyway as I’m sure they could use it and looks like a good way to learn more of the car.

 

[2001LC]

Your leak looks very minor. Re-torquing is certainly worth a try.

Some of that leaks looks like coming from power steering. Check you suction & return hoses coming from power steering reservoir. If wet and grimy they're leaking, replace hoses or re-clamping. Power steering reservoir has a screen in the bottom that needs cleaning at your miles, if not previously done and regularly flushed. Look under "Steering" in first link in my signature, for helpful tips!


Make sure to check your spark plugs. Spark plugs Alert Alert Alert!
A very small amount of oil may be at base of spark plugs, which is sign they're loose.

The PCV valve should also be inspected, along with both PCV hoses. If PCV system not in good working order, pressure builds in crank case. This cause oil leaks.

 

[chrisbruck]

My '04 was exactly the same. I just tightened down all the valve cover bolts ever so slightly. I bet you'll find some are barely hand tight and loose. Fixed my minor leaks for now and a whole lot cheaper and easier that replacing at the moment. Just don't go crazy overtightening them.

 

[Dannyboy lx470]

I will try to tight my bolts as I have a leake on drivers side and it's seaping on front CV axle or may have to replace gaskets.

 

[MoPops]

Just found this thread. Our 04 LC has had a tiny leak in the valve cover for a while. I had it in for an oil change and they brought it up. (Toyota dealer). I said no thanks it’s not too bad. $900 if they changed spark plugs out too. Got home from the oil change and the leak was quite a bit worse. Found this thread and tightened the bolts just a bit. All on the passenger side. They were barely finger tight. Checked the drivers side. Very tight. After tightening the passenger side bolts leak is gone. Not every day I get to save that much $$. May leak a bit in a while. I’ll watch it. Thanks all for the info here.

 

[nissanh]

FYI: Don't tight the bolts too tight. If you do, it can crack those "ears" at the corners. Seen that happening on 4runners and tacos. Those valve covers are super easy to replace. Always use OEM gaskets and apply a tiny film of toyota FIPG to the bottom of the gasket that meets the head ONLY on the side of the exhaust manifold.

 

[MoPops]

FYI: Don't tight the bolts too tight. If you do, it can crack those "ears" at the corners. Seen that happening on 4runners and tacos. Those valve covers are super easy to replace. Always use OEM gaskets and apply a tiny film of toyota FIPG to the bottom of the gasket that meets the head ONLY on the side of the exhaust manifold.

Thanks, it almost felt like they had been partially removed by the dealer. I’m sure that was just a coincidence. I had seen earlier warnings about over tightening. I used a small wrench, and just snugged them. Drove 20 miles after I tightened them, and no leak so far.