Valley plate question (1 Viewer)

[J54]

So my LC just went over 200K, and as part of my I’d rather fix everything before it breaks mentality I did the following.
1. Radiator
2. Starter
3. Valve cover and spark plug tube seals
4. Spark plugs
5. Water pump
6. Removed and resealed the heat exchanger cover (valley plate)

Got everything back together and I have a leak where that tube goes into the front cover from the heat exchanger. I installed new o-rings when I resealed it, and when I took it back apart everything looks perfect. I’m curious if anyone else had this problem or has a idea of why it was leaking.

 

[Sandroad]

Couple things…..
Is that an OEM ring? From the photo it looks a little ragged around the outside?
is that corrosion or dirt in the o-ring seating area. Either could lead to a leak, but if it’s corrosion you might need to figure out how to polish that up?

 

[J54]

All OEM parts. One thing I noticed is the O-ring is kinda wavy like it’s too big.
There is slight corrosion on the very outer edge which I polished as smooth as possible. In the actual o-ring seat there is just a little dust from taking everything back apart, it feels perfect.

 

[Sandroad]

All OEM parts. One thing I noticed is the O-ring is kinda wavy like it’s too big.
There is slight corrosion on the very outer edge which I polished as smooth as possible. In the actual o-ring seat there is just a little dust from taking everything back apart, it feels perfect.

View attachment 2670010

Hmm.....so maybe defective o-ring?

 

[Dixon Santana]

That o-ring can get pinched very easily when putting everything back together. This happened on a sequoia I did the valley plate reseal on. I used a light coating of sil-glyde over the o-rings so they don't get pinched when installing. No leaks after that, I've used this method a couple of times on other 5.7s I've worked on.

 

[J54]

Sounds like to be safe I’ll grab new o-rings and lube them up with more than the soapy water I used last time and reassemble it.

 

[sdnative]

Soak the o-ring and union pipe in coolant before installing. Goes right in no binding.

 

[04UZJ100]

Any lessons learned from performing this work? Kudos to you for DIYing it!