Is it a good idea to apply gasket sealant maker all around the valve cover gasket? to ensure no leaking in the future

 

What does the service manual say?
You don't put goop on things unless it's needed?
Note those 2 small spots that look a bit different (Kinda yellow?)? I bet they want a dab there ONLY! But that's just a guess.

But always follow the factory service instructions unless you have good reasons for doing something different?
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This, and do you know if they're reusable? FSM will tell you. Same with the torque spec on the valve cover bolts. . RTFM and you won't have to screw around with waiting for guesses on the forum.

 

I have found out that seals with lips or O-rings fails if extra sealant is added. Thre will be extra seams around where fluid is seeping thru.
As universal rule: Use sealant only alone on flat surfaces. There are positions, where extra sealant is required on rubber seal areas if there are joint or tight corner. This is then written in manual. (typically camshaft covers or oilpans)

 

You may be right the only places that look compromised are the two areas where the manufacture applied sealant everywhere else looks fine that is where it was leaking from I think

 

Do you have a service manual?
Have you read it?
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I do not have a service manual I downloaded the one you posted but could not find anything on valve cover

 

Is it a good idea to go with aftermarket gasket? or it must be OEM?

 

DO NOT use RTV or other sealants on the cam cover seal or spark plug boss seals. The only area to have an 8mm dab of RTV is where the timing cover mates with the cylinder head. I the picture, they're the areas near the front of the cam cover with the red arrows pointing to them.

I personally have not had good luck using aftermarket seals and gaskets on the AJ133/AJ126 as they fail prematurely. I'm sure others may have had success using the aftermarket gaskets and seals, but due to the amount of labour required to remove the cam cover(s), I would opt for the OEM parts.

 

Are timing cover oil leaks common? I can see oil at the bottom of mine
I cant tell if its leaking or the oil is from the valve cover that is leaking for sure
looks like the oil leaked down from the valve cover to the timing cover or the timing cover is leaking as well

 

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