Hey guys, I think I'm diving into a head gasket job on my daily driver. But before I do, let me rattle off my symptoms of why I think the Head Gaskets are gone.
I bought it about 4 months ago from the original owner, who never drove it in the winter. It's got 95k miles. Some of the "services" were written in sharpie marker on the bottom of the hood, and radiator support. (75k - Batteries) Best service records on a used vehicle I've seen here!

Cooling System - my antifreeze has been dissappearing over the last few weeks, and I've been replacing with antifreeze and distilled water to get back and forth to school.
Engine Oil - my engine oil level has been burning pretty good. I seem to burn about 1 quart per 250 miles (ballpark estimate).
CDR Valve - I haven't cleaned my CDR valve for fear of ripping/rupturing the diaphram with gasoline, on a daily driver rig. There's a good amount of oil spray on the inside of the intake in the rear, near the CDR valve. I probably should have grown a set and cleaned it anyways to avoid this current mess.
Engine - The passenger side rear cylinder has a sweet smell relating to burning coolant.
I have done many hours of reading, and have concluded that the extra oil sprayed into the intake by the CDR is causing increased BTU's in the rear cylinders. These extra BTU's tend to "lift" the cylinder head off the block, causing gasket failure. This seems to be my issue...does the burning engine oil have any relation to my head gasket issues?

Now, I've also got another '85 6.9 engine that has about 180k miles. It had the same low oil issue before the head gaskets went. At that time, early this spring, exhaust gas was forcefully coming out of my radiator. I thought it was cavitation because the force blew my overflow tank cap right off. I've got this engine sitting on a stand. About 4 months ago, I pulled the passenger side head off to confirm if the issue was a head gasket, it seems it was. My gasket was cracked and had red residue all over the edges of the coolant passages. So, this engine is an oil burner with failed head gaskets. Same as the current motor in the truck now.

Replacing the head gaskets are easier when the engine is out of the truck. I already have the head gasket kit, should I just do the head gaskets on the engine on the stand or do them on the engine in the truck? Completely understanding how heavy they are and limited room for moving.

What is "oil burning" caused by? Worn piston rings? Just the CDR? Valve seals?

I'm a community college student, and I'm on break for 3 weeks. I've been running the truck with the engine "as is" for 3 weeks now. Maybe I'll just keep going like that while I do the Head Gaskets on the engine on the stand? I really feel that the engine in the truck is in better shape, less oil spew out of the other gaskets, less miles. I'm never been inside, So I don't have enough knowledge to lean one way or another as to which is the better choice. I appreciate the opinions guys, I really do.

 

If we me, I think I woul do the gaskets on the engine that you have on the stand. And while the heads are off I would put valve stem seals in also, as these wear and allows oil to leak into the combustion chamber and burn. This may be where your oil loss was in this engine. I think you would be able to do a better job on the motor out of the truck.

 

Complicated question.

Red residue, many of the head gaskets had rubber inserts at the coolant passages, but some had a stripe of red silicone around the passages from the factory.

Oil burning, the older engines did use oil, mostly at the valve stem seal even with a new CDR.
So the oil were redesigned, no oil consumption, BUT since no oil was getting past the seals, the valve guides started wearing at a fast pace.
Sticking valves were also common with the new seals, so back to a less perfect seal.

With oil present in the intake, your CDR needs cleaned, and yes the oil mist from the CDR did cause the head to lift.
Engine oil has a higher BTU content than diesel, so higher cylinder pressure when it burns.

Do you notice coolant in the intake around the glow plug, there sometimes, not others?
I will say the extreme cold temps makes that leak worse, but then again the extreme heat of summer can do the same thing with higher cooling system pressures.

What would I do if I were you.

First I would check the blocks out to see which ones you have.
85 was the year the old and new style blocks were both used.

6.9 L Old Style Block

Block Casting Number:


On left side of block (beneath oil cooler) 1805440C1
Note: Some 440 blocks are truly new style and must be visually inspected by raised donut around the block heater, frost plug (right rear). Old style below serial number 173828.
Visual Identification: *No counter bored area for block heater
*No defined area on side of block for dip stick
*Thickness of cast iron around block heater 3/8" (.375")
Head Bolts: *7/16, 12 point socket is used to torque head bolts
*Block tapped with 7/16-14 for head bolts

6.9 L New Style Block

Block Casting Number: 1807996C1 Note: Some new style blocks have casting
number 440. Above serial number 173828.
Visual Identification: *Has counter bored area for block heater
*Very defined relief area cast in side of block for dip stick tube.
*Thickness of cast iron around block heater 15/32" (.470")
*Latest style (not all new style 6.9) has ribs around head bolts, rear two on left side go from head gasket surface to pan rail - same as 7.3
Head Bolts: *Same as old style 6.9

If one is old style and one is new style, I would fix the new style.

If you are lucky, the new style is out, the old style is in the truck if you have both styles.

After you check that out, we will go farther.

 

That would be a lot of oil to be going by the oil seals. Are there any oil spots where you park. The cdr valve will cause it to go through oil sometimes.

 

Thank you for the replies guys! I laid out a lot of background info up front, sorry for that long read!
Your right farmert, I'll be able to do a better job with the motor out of the truck. Nothin' worse than doing the same job twice, when it could have been done right the first round!
I'm thinkin' the gasket must have been that red silicone stripe from the factory. It looks pretty consistent in size/width around the holes, with just a little bit of smudge factory from being old. So, that's OK and not a concern anymore. Thank You Dave.
With the oil issue clarified, I'm just not going to worry about it since it's not related to my head gasket issue. I'll just keep checking and adding new stuff to keep her happy!
Coolant on the intake around the glow plug. OK..2 answers.
The engine that is OUT of the truck-before being pulled, the sunken areas where the glow plugs are, the drivers side rear-most gow plug would fill up with coolant and pour off the back of the engine. This is the same engine that blew the cap right off the overflow bottle.
The engine IN the truck - co coolant is evident around the glow plugs. The center of the motor is nice and dry. There is moisture on the passenger side rear section of the head. The exhaust manifold is wet, so I think the coolant is slowly leaking out (not fast like the other motor), hitting the exhaust manifold, and causing the sweet smell of burning coolant.

Good and Bad news. Bad - the engine in the garage on the stand is an old block. Good - it's not cracked around the heater. I plan to use a tank-type thermostat-controlled coolant heater in place of the regular engine heater, this will prevent any cracks in the future.

I'll check numbers on the engine in the truck tomorrow. I don't have very good luck, so it's probably another old block. I think I remember the title stating it was built in April...so that also leads me to believe it's an early block.

Nope, no oil spots where I park. That's what led me to believe it was an issue worth addressing. But, I'm just going to run with it and keep checking and adding. If it's not doing any internal harm to the engine, then it doesn't harm me either.

Thank you guys for your help.

 

Remember in 85 the new models came out in September.
It took lead time to build enough trucks, then ship them to every dealer before September.

I would put April close to the end of the 85 model and close to the start of the 86 model run.

 

Been a few days. I tried checking the numbers on the engine in the truck...tough to see with that oil cooler on there! I was spoiled checking numbers on the engine that's on the stand, I couldn't see the numbers so I pulled the oil cooler and then they were right there!
The passenger side valve cover has a sticker on it that has the engine manufacturing info on it. The tag is punched January of '85, so I'm pretty sure it's an early style block. I'll find out for sure tomorrow when I wire brush the block under the oil cooler better those numbers.
Regardless, the engine that's in the truck is receiving the Head Gaskets. It came down to the other engine having more miles and I remembered I had a knock in it. (Totally forgot about that! ) The engine that's in the truck has lower miles (95k), and is all around cleaner and tighter. I've got some ideas for the engine on the stand - Stock rebuild with bearings, seals, gaskets, new oil pump, and of course...Head Studs!
Last night I stripped all the accessories out of the way, and pulled the fuel system. I pulled the CDR valve and let that soak in gasoline while I pulled parts. Bunch of black gook came out! The intake manifold under the air cleaner was also very wet with oil, a small puddle was down there. I'm positive that is the reason for the Head Gasket failure. The burning oil raised the BTU's in the rear cylinder, raising the Head off the Block...giving me a Head Gasket failure.
Today I pulled the heads.
The passenger side head was the area I was suspecting issues, and I was right. The Head Gasket was split inbetween the 7 & 5 cylinders, and also between the 5 & 3 cylinders.
The drivers side was nice and dry. Of interesting note, the Head Bolts didn't seem to all be torqued down evenly. Some were tight like they should be, while 3 or 4 were still tight, but not as tight as every other bolt. I found it interesting because the Head Gasket didn't fail on this side with uneven torque on the bolts.
I'm doing these Head Gaskets while the motor is still in the truck. It is definety slow-going crawling up and kneeling on the radiator support for every bolt, standing on the innter fenders, and pushing up against the firewall for leverage. But it's all going well so far.
Tomorrow I'll scrape the mating surfaces, and put it all back together. I've been taking pictures here and there, and I'll post them by the end of the week when things settle down.
This has been a very frusturating experience, and I'm trying to be thorough in my posts so that other folks know why this happened, and that yes it is possible to do Head Gaskets in the truck if you're in a pinch. It's tougher, but it can be done.
However, if you service your CDR valve regularly (every other oil change), your Head Gaskets will have a better chance of survival.

 

There were two or three head bolts that you had to leave in the head till you pulled it.
You have to remember to reinstall those bolts in the head before you sit it back on the engine.

Take a piece of fuel line about 1" long, split the side with a utility knife and slide it over each of the bolts to hold them up while positioning the head.
Also use acetone and clean the block deck and head surface to get all traces of oil off before you put the gasket or head in place.

Lubricate the head bolts, sparingly with clean engine oil or molly assembly lube, again you don't want to contaminate the head gasket with lube.
A drop or two spead around the threads with your finger is plenty.
Check the rockers for wear, if you have the dollars the 7.3 style rockers is a bolt on swap and much stronger.

 

Ut oh.
I pulled all the head bolts from each head before pulling the head off...is that bad? Or are you just saying that because it's tight up against the Firewall and Brake Booster/Master Cylinder. I pulled the heater core to ease removal on the passenger side. Big help!
Thank for the tips on the acetone, I'll get some before jumping back into the truck in the morning!
I was planning on running all the head bolts through the wire wheel that's on the bench grinder. That'll take care of the rust/corrosion.
I read about the engine oil on the head bolt threads in the Chilton Manual. Thanks for telling me to go easy! I was gonna coat them good, not anymore!
Rockers seem nice and tight, don't have too much wear. The 7.3 rockers were on the list for the other engine on the stand, thanks for the reminder.
Thank you for the tips and help!

 

His description of the last head bolts is only if you did not remove the HVAC box off the firewall, which sounds like you did so diregard.

 

ohh ok. Yeah, if i hadn't pulled the HVAC box off the firewall, clearance would have been tight!
Takes a few minutes to remove it, but it makes everything easier.
Of course pullin' the motor would make things a whole lot easier too! I'm 19, I'm sure I'll be doing IDI head gaskets a few more times.
Actually, I have two motors. The whole point of keeping the spare motor was to rebuild it and have it ready to throw in the truck if the Head Gaskets failed. I figured that with 95k miles on the engine, I had a little more time until they went. Oh well. I'll have more time to get the spare motor rebuilt and ready to throw in the truck.
I'm concerned with DOT inspections. In Mass. anything over 10k lbs GVW requires a DOT number and inspection. I've been doing my small landscaping business "under the table" for a few years now. This year I wanted to put a sign on the truck and everything. But, I'll need a DOT number and inspection. A single oil drop will fail DOT inspection...so I thought ahead and am going to get this other motor leak-free and a little stronger and reliable.
Sorry for the rant, thanks guys! Pictures will be posted in my gallery if anyboy is interested in what's involved to prepare to do the job themselves.

 

Don't sweat it, I've done it both ways, just take your time and don't take any short cuts and keep everything clean. You only want to do it once.

 

Yes if you didn't pull the heater box, the bolts would not have come out of the head.

 

After 7 days of "fun", the engine's all back together. After pulling the driver's side head, the glow plug terminal had the spade end of the terminal stuck inside, with the glow plug in cylinder #8 broke off 1/8 inch under the deck height...leaving the rest of the plug stuck in the hole. The plan was to drill straight down, and then we would pick the threads out with a part of dental picks. So, we patiently tried to drill it out. We got down to the bottom, where the hole tapers, and broke the drill bit. Now, the drill bit was stuck in there too. That was Saturday. Sunday we tried more to drill it out...got nowhere trying to drill out a Cobalt drill bit. That stuff is hard material! Monday morning I brought the head to a machine shop, and they took care of it, for $150. Cool, problem fixed.
Two days later, got the head back, and bolted it all up last night. This morning I finished bolting on all my other stuff. So, it became starting time about an hour ago.
But, i got a problem!
I cranked it over, then when I was letting the starter cool down between cranking cycles, I found a coolant leak! Or maybe the head is cracked...
It's cylinder #1. Front passenger side cylinder. I have coolant bubbling up from between the head/valley pan/intake manifold seam. It bubbles by gravity, because it will leak wheh the truck isn't cranking.
The head was bolted down and torqued to spec in a 4 step pattern. First round-40, second round-65, third round-85, fourth round-90. I thought I read somewhere to go a little higher with used bolts, so I took it an extra 5 the last round. It all snugged down nice and evenly...at least it felt that way.
Unfortunately, it seems like the head gasket is shot huh?
I have a picture, but I don't know how to post it in the thread for you to see.

 

It is possible that it is your intake instead of the head, did you use a new valley pan.
With the head torqued down it would have to be a major leak to leak without compression causing it.