Should I Purchase: Feb 85 6.9?

[OldIron82]

Hello all. I found a truck at a local salvage yard that had a 6.9 in it with a first gen Banks turbo on it. There was a sticker on the radiator support with emission information from California. I don't know if it came from factory with it but it just struck me odd that there would be a sticker about emissions on the truck. Its a 85 f250 2wd c6 with a gear vendor overdrive. I purchased the turbo kit off of it about 2 months ago but then i found a entire engine, an 83 6.9 with 85,000 miles on it and the grandson of the owner installed a first gen Banks with bb injectors. After being schooled about the wonderful cracking problem on this block, my thought is now to return to the salvage yard and purchase the engine that I got the turbo off of. $200.00 asking price.

Here is the problem, the cooling system is milk, and the oil is too. I heard it run, and it was missing horribly and the upper radiator hose was ballooned rock hard and if you cracked the rad cap after you shut off the engine it would depressurize and hiss loudly. I'm thinking head gasket for the cooling system pressurization, but the oil scares me. Could this engine possibly fallen victim to the dreaded cavitation, or maybe is the oil cooler shot? My biggest concern is the piston cooling jets, whether or not they are bolt in or the dreaded once and done. I found this out thanks to The Warden in my introduction thread (thanks again!) as he posted a awesome page about 6.9 upgrades. I cant read the serial number on the valve cover anymore, but I can see February 85 is marked. The only thing I can visually confirm is the highly pronounced recess in the block for the dipstick tube. Where else is a serial# located?

What it all boils down to is this: I'm just interested in the non ******* block (assuming it is) to do a reseal and head studs with a turbo. It is for my 88F350 dump that currently has a NA 7.3 with a zf5.

How much will flip flop between the Oct '83 6.9 and the Feb '85? Oil cooler, heads, etc?

Would It be worth yanking the guts out of the low mileage 83 and putting it in this 85 block?

I have a feeling this entire idea is bad but I really wanna do this 6.9. I in no way shape or form can tie up the truck for a massive fabrication project of a dt360 at this time. Nor do i want to put in my buddies first gen 12v that he practically wants to give me because he wants it out of the barn because I'm over the Cummins thing.

Thank you everyone. I know this thread is all over the place, i tried keeping it as organized as possible. Look forward to any replies.

OI82

 

[79jasper]

I could be wrong, but I think everything will swap.

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[The Warden]

I cant read the serial number on the valve cover anymore, but I can see February 85 is marked. The only thing I can visually confirm is the highly pronounced recess in the block for the dipstick tube. Where else is a serial# located?

First, thank you very much for your kind words! I'm glad I was able to help.

As to the block serial number, it's just as well that you can't read the number on the valve cover...there's always a chance the valve cover was replaced, which would mean that the numbers on the valve cover sticker don't mean anything. Besides, I'm not sure the block number was originally printed on the valve cover sticker to begin with.

More importantly, the "primary" block serial number location is on the block itself. It may be hard to see and/or covered in gunk, but it's stamped into a flat spot on the block, to the driver's side of the injector pump drive gear housing. I found this picture to give you an idea (found via a Google image search):

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The top of the picture is towards the back of the engine, with the edge of the IP drive gear housing below and to the left, and the coolant temp sensor to the right.

Every serial number starts with 6.9D U2U; the numbers you're looking for are after the second U...so, the example in the picture is Block #010464 a very early 6.9L block. In fact, it's even older than my block (my truck was assembled in August '83; my engine's Block #061494).

As to the emissions sticker...the turbo install was probably done by a shop. Banks supplied the sticker to show that the engine with the turbo installed still meets emissions requirements in CA...it's really just a CYA move in case the vehicle ever got inspected for emissions purposes, which they're not doing to pre-'98 diesels in CA yet. That's for another thread

Cavitation on a 6.9L is rare due to the cylinder walls being thicker, although it's not unheard of. I would guess that an oil cooler seal failed on this engine.

Accessories can all interchange between any 6.9L or 7.3L IDI; that's one of the beauties of these engines I should note, however, that early 6.9L's use a different style oil cooler...you can transfer an entire oil cooler assembly from one engine to the other, but you can't mix and match pieces of an early oil cooler with pieces of a later oil cooler. Also, there are some differences between the engines used in F-Series trucks and the engines used in E-Series vans; IIRC the oil cooler assembly is different, and the exhaust manifolds are considerably different. But, swapping parts from one engine to the other is easy enough

I'm not sure what model years the block numbers correspond to, but as far as avoiding the piston oil cooler jet and weak block issues are concerned, your best bet is to go as late as possible...'87, or maybe mid to late '86. Or, go to a 7.3L...if you're rebuilding the engine anyways, you can sleeve the block. Once you've done that, be strict about SCA's in the cooling system, and you'll minimize the risk of cavitation.

Hope this helps some

 

[OldIron82]

Thanks for the quick replies gentlemen. Warden, right on the money with the serial # location. Looked at the '83 engine and well..................54366. D'OH! What a shame. The engine is in such nice shape but that is way too low on the totem pole of upgrades for me to want to deal with. Tomorrow I'll head to the salvage yard and ascertain the number on the 85 block got the turbo off of. Boy I hope it hits the cooling jet bolt in years.

 

[IDIBRONCO]

Just my opinion, but s/n 54366 doesn't really seem that low to me. Also if the engine in your '83 has a deep recess for the dipstick tube, it sounds like you have the updated block. I could be wrong, though. As for just putting the internals from one engine into another, that would basically be a rering. Just measure everything CAREFULLY to make sure it's still in spec. Be sure to use new rings and bearings of the correct size (you didn't specify exactly what you'd be doing). Otherwise, if everything measures as good, go for it.

 

[The Warden]

Just my opinion, but s/n 54366 doesn't really seem that low to me.

I respectfully disagree. My block s/n is 61494, which is higher than that, and my block's original to an August 1983 build truck (technically 1984 model year, but it had to have been one of the first of the '84's). The updated block started with s/n 173828, which is generally understood to correspond with midway through the 1985 model year.

I posted this in the earlier thread, but I'll re-post it here for reference...

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[OldIron82]

Weeeeeeeeell.........184819. ( The '85 engine at the salvage yard ) Updated block: Yes. Bolt in jets: NOOOOOOOO!
ERRRRRRR! ***********************!!!!!!
Ok. Now let me ask: How much of a deal breaker are these once and done jets? The non ******* block is a no brainer, but would you seriously completely steer clear of it anyway because of the jets? I really want to get started on a engine and I don't want to spend the time to find a bolt in jet block because the way this is going the snow will be flying. At this point, I might as well stud the head on the 83 and drop it in and just not use the block heater and hope for the best. I don't want to do it twice however. Thoughts gentlemen?

Thanks OI82