replace head gaskets 6.9 diesel

[Riley]

Thinking of replacing the head gaskets on my 6.9 in an 1987 F-250 with 114,000 miles on it because these seems to be a slight coolant leak on the rear drivers side. How much problem to do this with the engine in the truck, and approximately what do those heads weight?

I am also considering putting on a turbo kit due the the high altitude driving I do with this truck, so I assume I should either replace the bolts or put in studs?

I'm new to these engines so I don't want to do anything I will regret (have to pay for) later.

 

[david85]

The heads are 100 lbs each, so you will need a hoist or helper to remove and install them. The ARP studs near the firewall will have to be installed with the head because they are longer than the stock head bolts. I would recommend installing heads studs if you plan on installing a turbo even in the distant future. The are reusable and if you ever do get a turbocharger, its really not that much to pay for some piece of mind.

If your coolant is confirmed to be coming from the head gasket, than its best to replace it as soon as you can. Diesels run such high combustion pressure that any breach of the fire ring of the head gasket can cause erosion of the head and block mating surfaces. The longer you wait, the worse it could get. One way of knowing if the fire ring has been breached is if its consistently building pressure (that does not go away on cool down) in the cooling system and blowing bubbles out the recovery tank.

Due to clearance problems at the rear of the engine bay, some recommend pulling the whole engine to do the head gaskets. ARP also recommends going through the torque sequence up to 6 times to maximize the clamping force and minimize the friction in the bolt threads. Either way, you are probably looking at 3 solid days of work assuming you have everything you need in front of you.

 

[6.9poweredscout]

Thinking of replacing the head gaskets on my 6.9 in an 1987 F-250 with 114,000 miles on it because these seems to be a slight coolant leak on the rear drivers side. How much problem to do this with the engine in the truck, and approximately what do those heads weight?

I am also considering putting on a turbo kit due the the high altitude driving I do with this truck, so I assume I should either replace the bolts or put in studs?

I'm new to these engines so I don't want to do anything I will regret (have to pay for) later.

they are HEAVY! one head on my 6.9 weighs more then the BLOCK on my buddy's honda prelude!!

-Jon

 

[towcat]

the question is...how strong is your back?
the driver's side is difficult, the passenger side with AC is a downright bear. the rearmost bolts will have to be supported on the valve once they are loosened up since the AC housing will prevent removal. I couldn't tell you how many techs have made the mistake and forgotten to put them back in before installing the head.
If you can, do yourself a favor and pull the motor. Your back will like you a little more and you also have a chance to regasket the lower end.
good luck

 

[h2odrx]

I did mine in the truck, never again, it took me a long time......

 

[RLDSL]

I did it once with the engine in, not fun, but doable with a cherry picker. if the thing has had fel pro gaskets on it before, you will have one hell of a mess to scrape off and without being able to flip the block on an engine stand, you'll need to flush the cooling system out GOODwith the thermostat out after getting it back together. It would be impossible to not get crud down in the cooling jackets and you wil make another nice mess bottom tapping the head bolt holes.
Not sure about your year, but on my '92 , removing the engine side cover of the AC evaporator housing made for oodles of clearance to get out head bolts and get to everything over there.

In the long run, it really is less work to pull the engine

 

[Riley]

Thanks for the great feedback. I do believe that I will pull the engine to do this job, and probably will also put on a turbo kit at the same time. When I do get ready to do this job you'll likely see me on here quite a bit, asking for tips, etc.

 

[RLDSL]

If you pull the engine, do yourself a big favour and remove the core support so it can come straight out. and to top it off, pop the cab mounts ( good time to replace them anyway is installing a turbo, give you some more clearance ) and jack the cab up on about 6" of wood blocks ( thanks towcat for that trick
It gives you a ton of room to work and at least my 088 ATS turbo can go in and out still attached to the engine that way with room to spare

 

[david85]

We've got a 1.5 ton chain hoist hanging from the main beam of our shop so I had the travel needed to remove the engine without having to remove the core support. In fact the engine drops in and out quite nicely with only the hood removed. No need to turn it sideways or anything. When I put it back in, it just went down and back without much fuss. A good shove was all it needed to get the bolts to drop into the engine mounts.

If you don't have a tall crane to lift the engine high enough to clear the front end, than just pull the front end out. Its worth being able to know that you did the engine right. Getting a torque wrench to reach some of the rear head bolts will be a challenge with the engine still in the truck.

I did an in frame head job on my dads 6.5 once and never again. The 6.9 comes apart a little easier on the top, but its also a tighter squeeze in the engine bay because its overall a larger engine.

 

[Mr_Roboto]

I'll probably get slammed for this - but - every time you take something apart you take the chance of breaking something else.

What you have is a low pressure coolant leak. Bar's will usually take care of things like that, if not the ceramic block sealer will.

 

[FordGuy100]

I'll probably get slammed for this - but - every time you take something apart you take the chance of breaking something else.

What you have is a low pressure coolant leak. Bar's will usually take care of things like that, if not the ceramic block sealer will.

Well aint that the truth . Thats usually what happens, you do something, and something else needs fixed, or breaks and needs fixed. Oh well

 

[Riley]

Mr. Roboto,

What is the ceramic block sealer and who carries it? I am not familiar with that product. As far as the Bars, I have used several times with gas engines and radiators and it has always worked. Just did not know if it would work with the high compression diesel.

Also, should I attempt to retorque the head bolts? I have done that with a ford 390 engine and it took care of the head gasket leak, but I know we are talking different engines here.

 

[Mr_Roboto]

Mr. Roboto,

What is the ceramic block sealer and who carries it? I am not familiar with that product. As far as the Bars, I have used several times with gas engines and radiators and it has always worked. Just did not know if it would work with the high compression diesel.

Also, should I attempt to retorque the head bolts? I have done that with a ford 390 engine and it took care of the head gasket leak, but I know we are talking different engines here.

The Bar's does not care what the engine is. You don't have a compression leak - you have a low pressure leak between a coolant passage and the outside of the engine - no different than a seeping hose, radiator pinhole etc.

The ceramic sealer has become popular in the lat 10 years. Many manufacturers make it. Rather than sealing a leak, it coats the entire inside of the cooling system with a ceramic film. In the past I used it to "repair" a 351W in a truck that was "severely" overheated and was burning water in abundance.


My recomendation would be to put a couple bottles of Bar's in, then if the leak stops then use the ceramic sealer to put a "hard seal" behind the softer Bar's plug.

I don't think there would be any harm to retorquing the head bolts.


I can tell you right now there are 2 bottles of Bar's HD on the shelf at my shop. I will often install it for customers who have minor head gasket leaks or leaks so small that they cannot be easily located. With so many of my customers struggling to survive and some of their cars on the "ragged edge" I cannot justify recommending major repairs for a minor problem.

 

[Agnem]

I really need to get this article posted over here, but at least over 40,000 have looked at it at the old site.

Headgasket replacement article.

 

[Optikalillushun]

hope i never have to do this