Black sludge/deposits under valve cover - problem?

Ford420

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Long time since I last posted. Searched and didn't find anything that matched what I'm finding.

The valve covers on my '86 6.9L haven't been off since the engine was rebuilt in 2010. Since then, the truck ran for a while without a turbo, then got the Banks Sidewinder system installed about 30k miles after the rebuild. I'm replacing all the injectors due to high EGTs and noise from several of them. I'm also replacing the injection pump. So, I decided to replace the valve cover gaskets to stop a couple small oil leaks. I took the cover off the driver's side and was disappointed to see deposits (black tar-like sludge) caked on the head, under the #4 and 6 cylinder rockers. The passenger side has none of this though. Is this common to only see buildup on one side? Does it indicate a problem, or is it pretty common?

Driver's side head:

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Driver's head, wide shot:
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Passenger side (clean, no deposits there!)

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For the last several years, the truck only gets driven 2-3 thousand miles a year. It gets annual oil changes, but sometimes is only taken on short drives (not reaching full temp). I run Lucas oil stabilizer (one qt) and Delo 400. I don't have to add any oil between changes. It does run quite cold - think the thermostat is stuck open. Could running cold cause this buildup? I'm installing a new Motorcraft thermostat as part of this project. Crankcase vent is via oil filler neck Banks adapter and hose to the inlet of turbo.

No oil in coolant, no coolant in oil, have not yet completed compression test... re-installing injectors and pump and will get to that.

Should I just throw it back together and run it? Thanks for any advice you have. - Chris
 

Nero

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Interesting, usually I only see buildup like that when people do prolonged oil changes. But for only one head? Hmmm....
Maybe a bad exhaust valve stem seal, or only have stem seals on one head? Grasping at straws here.
 

Ford420

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Thanks for the reply Nero. The fact that it's only on one side and only in the middle of the head threw me off too. I suppose the compression test will tell. I am 50/50 on whether to try and clean it up with a solvent.
 
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Old Goat

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Running cold, taking it on short drives and not getting up to temp.
Only driving 2 -3K miles a year and sitting most of the time, could
be some of the issues.

A few years ago both Valve Covers were a leaky mess. I cleaned up
the Drivers side, removed the bolts and washers, cleaned them up in
some solvent. Sprayed Carb Cleaner in the threaded holes, blew them
our with air. (place a rag over the holes) Added blue lock tite to the bolts
and cinched the down. For the most part that side is dry. Did have a bit
of seepage and tightened those bolts. and still good.

Pass side haven`t done yet.... oily mess. It`s scheduled.

Goat
 

Ford420

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Goat,

I am hoping the buildup is just because of the cold coolant temp and infrequent use, as you point out as possible causes. I'll post the compression numbers as soon as I run the test.

I really like the GV. I wired it directly to the switch on the shift lever, bypassing the GV analog control unit. I just have to remember to kick it back to 1:1 as I come to a stop. However, if I do forget to disengage the GV it just upshifts smoothly to OD once accelerating past 15-20 mph (usually 2nd gear) so it's not a detrimental issue. I am going to wire a relay into the power lead to the GV because the switch occasionally gets hot with the current running through it, oddly enough.

At freeway speeds, shifting out of OD (clutch disengaged) sends quite a shock through the driveline that I'm not very fond of. But, no U-joint or other driveline issues have occurred thus far. I spoke with GV tech and they advised that it's a common issue and gets better with more miles. OK, but I have about 15k miles on it and it still does the same thing. The drop in cruising RPMs, lower cabin noise, better fuel economy, and ability to get above 75mph are well worth it. Splitting second to third is a godsend when towing. Third OD is somewhat helpful, but only about 300 RPM higher than fourth.
 

Old Goat

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Thanks for the reply.
I pulled a GV from PNP couple years ago out of a 89, 7.3, C6 trans.
Grabbed the GV, $160, then back next day with more tools, for the adaptor, $34.
Now looking for the T-19 adaptor.
This is the first one I have come across all the years going to PNP.
A 2 spd rear end switch should work really well., good tip on the relay.
Actually forgot it was out in the shop.


Goat
 

Ford420

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Goat - That's a great find at PNP! If you need parts or want to get the unit tested and rebuilt, GV can do that - for a healthy fee of course. They may not be very cost effective, but they do support the product no matter if you bought it new from them or not.
 

Ford420

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As for my valve cover gasket project... I will not be getting to the compression check after all. I decided to pull the rockers to investigate further and to check torque on the ARP head studs. Well, much to my chagrin, the #4 exhaust valve has a lot of side-to-side play in the guide. About 3/32" of play. So, that's toast. And, since it's studded, I get to pull the engine (yay) to get the head off. Well, could be worse. If I didn't take the time to look into it now the valve could have bent or dropped. Now I'm praying no other damage has occurred so it can just be the heads I need to get redone.

Either way, I'll likely take this opportunity to upgrade to Inconel valves, if they are even available for the 6.9 anymore, or ever were? If anyone has info on availability please let me know. Thanks!
 

IDIBRONCO

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WOW! Yep. Time for an engine pull. My opinion is that you might as well do both heads. They both have (probably) the same amount of miles on them.
 

Ford420

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IDIBRONCO - I agree. While it's out, I'll take the time to check everything and upgrade the valves. I'm sure I'll be back here with questions once I start the project. Looks like it's going to sit in the corner of the garage for a while longer before I get to it though :(

I MISS DRIVING MY BABY!
 

IDIBRONCO

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I'm sure you do. You'll be able to drive it A LOT longer after some loving care is given. Maybe some four letter words too. They tend to slip out from time to time. At least around my place.
 

Old Goat

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Goat - That's a great find at PNP! If you need parts or want to get the unit tested and rebuilt, GV can do that - for a healthy fee of course. They may not be very cost effective, but they do support the product no matter if you bought it new from them or not.
I talked to them before. I seem to have $800 in my head, but probably much more.
I will have it checked over before sticking it in.

There is a deeper sump available, here is a thread.

This guy added a filter and pump to add longivity.

Here is a couple things from same guy on another forum.

I extended my drain intervals by installing an external sump w/filter, increasing the fluid capacity to about 5 quarts:
http://stuff.is-a-geek.net/PhotoAlbu...cs/CTD_125.jpg
http://stuff.is-a-geek.net/PhotoAlbu...cs/CTD_126.jpg

It was fairly easy and inexpensive by my estimate. Mostly stuff from the big auction site - Mack truck steering resevoir/filter($30), old style Autopulse pump ($25), maybe $30 worth of tubing, clamps, barbs, bolts, etc. plus some scrap steel for custom-made brackets to bolt the stuff on with. You can't buy those, gotta make it yourself. I installed it after the first year and oil change at about 6k miles on the first fill, IIRC. It's got 18 months and around 15k miles on this sump. I'm going to let it go 2 years and see what it looks like. Maybe longer next time, we'll see...

I run the pump once or twice a week for just a few minutes at a time on the way home before pulling into the garage to keep fresh, clean oil in the GV.


Back to our regular scheduled program.



Goat
 
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