Terrible look under valve cover

What is this? Leaking Exhaust gas? Engine oil not changed enough?

 

Looks like typical sludge

 

Infrequent oil changes

 

It’s hard and crusty

 

^^^^ This. Oil wasn't changed frequently enough and the contaminants eventually baked into the mess you now see. I've seen engines - with regular oil changes - with 200,000 miles on them that looked almost new.

 

The oil wasn't changed often enough and/or some crappy oil was used at some point in that engines life.

 

looks like oil wasnt changed regulatory.

 

I would guess poor quality oil that was not changed often.

 

Almost looks like someone used frigin ATF in there.

 

Looks like my dads truck. “It’s a Toyota, it will be super reliable even without oil”

 

Also possible it had a lot of short trips with extended oil change interval. They consider short trips severe duty, because water moisture gets mixed with the oil and covers everything, but does not get hot enough to evaporate off.

 

Yeppers....... combination of low quality oil filter, low quality oil or infrequent oil change. Any combination of those 3.

I think it is recoverable. Just shorten the oil change interval, high quality oil and high quality oil filter. Time put the sludge there, use time to remove the sludge. You don't want it all breaking loose at one time. The high quality oil should help dissolve/remove the sludge. High quality filter should capture the bits. More frequent oil changes will keep the oil (solvent) fresh.

 

I recently bought. 2013 with some crud, not as bad as that. Been doing short oil changes and putting in MMO about 300-400 miles before the change (using quality filters).

The MMO has helped but there is some chance of clogging up stuff if it removes too much at one time…

I used a full quart 2 times… haven’t decided if I’m going to do another full quart next time or reduce it from here on out…

MMO will thin out oil too so I have been using a thicker 5w30 euro oil when I use a full quart.

With that much crud I would probably run some good oil on short oil changes to clean up as much as I could as others have said.. probably with 5-10 oz of MMO to help some.

To be clear I remove a quart of oil and replace with a quart of MMO. Again I’m not sure I would do it with that much crud… I would use a smaller amount of mmo in the oil the full run, but of course that is my unprofessional opinion.

Of course do at your own risk.. I take no responsibility if MMO breaks it up too fast, but it is what I would do because I’m OCD about a clean engine.

 

What's the mileage?

 

I was thinking MMO also. Good call. Also now that it's exposed I would get a lint free rag and some brake clean and wipe it down best u can, then do what mgaines suggested with the MMO. Good luck and keep us posted.

 

Thanks, bought the truck not to long ago so I have no idea about frequency of oil changes. I’ll try maintaining it like Knute mgaines74 suggested. Any other ideas on what to use to clean every thing while I have the head off?

 

yeah definitely agree.. manually clean what you can.. I would have a shop vac to help with that..

 

I have never manually cleaned that much crud so maybe someone will chime in with more experience with that procedure.

I have read that Berryman B12 chemtool is some stout stuff that works well. You don’t want to breath that stuff in too much and don’t get it on your paint.. and of course wear gloves.

I would also run an extremely short oil change after it is put back together to make sure you get any crud that may have fallen into the engine.

good luck

 

^^This^^^
Just for comparison I recently replaced my valve cover on my 4cyl sonoma with 146,000 miles and this is what it looked like. Proper OCIs go along way IMO.

 

I would do a used oil analysis through a company like Wix (ALS Tribology) or Blackstone before you do anything else. See if there are any non-visible problems with the motor before trying to clean up that mess.