Regional sludging? How to deal with it?

[Oro_O]

I opened the valve train on my SUV tonight to replace some leaking vc gaskets. I found an annoying problem, that the back upper quadrant of the valve train appears to not get enough oil splash and what residual does, cakes and cokes.

Vehicle is a 1998 Acura SLX (Isuzu 6Ve1: http://en.wikipedia.org/wiki/Isuzu_V_engine), 161k miles. Documented 3~5k Jiffy Lube type changes until 130k. It consumed oil (these do, they have a ring design/drain problem like Saturns or recent Toyota 2.4l I4's). I ran Delvac HDEO to clean things up for 10k, then treated with SeaFoam to soak rings and oil use dropped dramatically. Switched to Pennzoil Platinum 5w30, and 500 miles later oil use spiked, I think because of VC gaskets leaking. I found a spark plug journal full of oil, for example.

Anyway, I found the valve train looking OK on opening it up:

But the in the upper back corner it looked like this:

This is the only part that has these fine carbon granules. The cover looks the same.

So I am trying to figure out what to do. I cleaned the cover with a brush and acetone, and left soaking in diesel overnight to get as clean as I can. I can't repeat that on the rear of the intake cam, though.

I haven't taken the cover off the other bank yet, but suspect the same.

 

[suspiciousmind]

If you can get a thermostat that opens a bit earlier, that would help. That's a hot spot.

 

[Donald]

Auto-Rx? I would replace the thermostat as a first step. They are a maint. item anyway.

 

[Olas]

Agree with the thermostat to prevent reoccurrence, I'd hit the grime with brake cleaner and a stiff brush and try an hdeo for its (supposedley) better cleaning

 

[tig1]

My grandson has a 2002 Toyota Camry V6, 195K which is a sludger. He had the rear valve cover replaced last week because it was leaking. I ask the mechanic to inspect for sludge and he said it was very clean for the mileage. He bought the car with 115K on it. He has followed my OCI of 10K using Mobil 1 5w30. Most all miles are local as he runs a pizza route. The key to less coking and sludge is to use a quality synthetic oil. IMO.

 

[2004tdigls]

go back to a high detergent HDEO and continue to use it.

any CJ rated 15w40 or 10/30 would clean up the engine

 

[OVERKILL]

I'd probably try Mobil 1 0w-40 to see if it can help clean it up. Though the Delvac product was also an excellent choice there.

 

[ARCOgraphite]

Looks like a oil dripper isn't open over there.

 

[Oro_O]

Originally Posted By: ARCOgraphite
Looks like a oil dripper isn't open over there.


I wonder about that. I cranked it over and the adjacent cam lobes get oil, and there is oil puddled under them equal to all the others. I wonder if it's just a dry area and that happens.

Again, that was after 16,000 miles with Delvac HDEO. I don't know what it looked like before, though. I will get at the other side today to compare (that cover is much harder to access).