Is this a valve cover or cam tower oil leak? (1 Viewer)

[swild]

I posted this over on the Lexus forums but didn't get many answers. What do you guys think?

These pics were taken from the passenger side wheel well looking towards the rear of the engine.

 

[jeremy j]

Looks like a leaky valve cover gasket to me.

 

[Acrad]

I would clean it up with brake cleaner and monitor to determine if both

 

[jgalt]

^ Agreed. It does "look" suspiciously like the tower leak location however.

 

[swild]

^ Agreed. It does "look" suspiciously like the tower leak location however.

I'm confused because every time I see a cam tower repair video, the cam towers always look like they exist fully inside the valve cover. I don't see how they could leak out.

 

[jgalt]

Nope, it is actually another stacked layer. Hence it adds another interface/leak path. Head deck, cam tower plate, valve cover, from bottom to top.

 

[swild]

Nope, it is actually another stacked layer. Hence it adds another interface/leak path. Head deck, cam tower plate, valve cover, from bottom to top.

Ahh, I get it now. Thanks for the insight. Well, I guess it's time to do the timing cover, cam tower, valve cover leak repair!

 

[jonshonda]

Looks like a valve cover gasket leak to me. Physics and gravity will concentrate the majority of the oil in the back corner like that. It wouldn't hurt to use a 1/4 drive ratchet (note I said 1/4" drive due to the low torque needed) and just put a little effort into turning the valve cover bolts to see if they are loose.

I'm not familiar with the 4.6L valve cover fasteners (yet! knock on wood) but the 4.7L had rubber washers attached to the bolts that held the valve cover on. They naturally contract and expand, and I know sometimes a simple fix was to tighten them up slightly. ymmv

 

[jgalt]

^What I'd do too. Unless one is really bored and wants to perform invasive surgery for fun, try the simple things first. If that doesn't work, go nuts.

 

[swild]

Well, my timing chain cover is leaking pretty badly. I think I'm gonna have to do the whole thing here soon.

 

[jgalt]

^ In that case, agreed! Depending on your miles, maybe a whole host of other things to consider doing too.

 

[r2m]

Well, my timing chain cover is leaking pretty badly. I think I'm gonna have to do the whole thing here soon.

If you'll be doing the work yourself, can you take lot's of pics and do a detailed "how-to"?
Many on here would be grateful.

 

[swild]

I'm just going to be following this dude's post: DIY - GX460 Valve Covers, Cam Towers, Coolant Valley and Timing Cover - https://forum.ih8mud.com/threads/diy-gx460-valve-covers-cam-towers-coolant-valley-and-timing-cover.1334342/

I've already done the coolant valley plate leak. This is probably going to be a bit more challenging, but I'm up for it.

 

[jgalt]

^Good on ya! Just curious, since these things take time, I assume you have other transportation in the interim? Maybe you have the luxury of spreading out the work over several days?

 

[swild]

^Good on ya! Just curious, since these things take time, I assume you have other transportation in the interim? Maybe you have the luxury of spreading out the work over several days?

Yep, got another car to use. I'll probably do the job over the weekend.

 

[jgalt]

^Good call! I make mistakes when tired or rush things. If you successfully did the valley coolant plate fix then you know patience. I'm curious how much the timing chain cover is going to fight you.