Motor swap considerations

[TWeatherford]

Well yesterday I picked up an 85 6.9 with what I believe to be 110,000 miles on it. Its pretty nice, starts and drives really well, and is awful quiet for what it is. Best of all, it has a Banks turbo on it, though with the C6 auto its still a little gutless. I am going to put it in my truck and have a few questions.

Any suggestions on what to do to this thing before I stuff it in? I'm going to do some stuff, like the rear main seal and a good cleaning, but money isn't endless so not as much as I'd like. I might need to look at the turbo, the most I ever got out of it was 6 psi (although I'm not totally sure the gauge is good). Need to figure out how to make the pyro work, hopefully an easy fix and not a new gauge. Going to switch this motor to serpentine belt, and in a lucky modded 11" flywheel between it and my zf5.

I feel a bit sad parting out this old truck. Just the little I drove it to get it home, and around the ranch for kicks, its pretty neat. Runs and drives really well, especially for an 85. An older man owned it for all but the last 7 months and took care of it from what I can tell, didn't even have any hitch on it but a ball bolted into the bumper. Only rust is above the rear wheels, other than that its pretty clean.

 

[RLDSL]

Miles are pretty low, could be the low boost is due to the fuel having never been turned up after the turbo install, and you can be sure the pump and injectors are original and timed as such. a little timing advance would help.

 

[91f2504x4]

Well yesterday I picked up an 85 6.9 with what I believe to be 110,000 miles on it. Its pretty nice, starts and drives really well, and is awful quiet for what it is. Best of all, it has a Banks turbo on it, though with the C6 auto its still a little gutless. I am going to put it in my truck and have a few questions.

Any suggestions on what to do to this thing before I stuff it in? I'm going to do some stuff, like the rear main seal and a good cleaning, but money isn't endless so not as much as I'd like. I might need to look at the turbo, the most I ever got out of it was 6 psi (although I'm not totally sure the gauge is good). Need to figure out how to make the pyro work, hopefully an easy fix and not a new gauge. Going to switch this motor to serpentine belt, and in a lucky modded 11" flywheel between it and my zf5.

I feel a bit sad parting out this old truck. Just the little I drove it to get it home, and around the ranch for kicks, its pretty neat. Runs and drives really well, especially for an 85. An older man owned it for all but the last 7 months and took care of it from what I can tell, didn't even have any hitch on it but a ball bolted into the bumper. Only rust is above the rear wheels, other than that its pretty clean.

While I had the motor out I would probably go ahead and replace all the seals and gaskets that are prone to leaking. If you have the money it probably wouldn't be a bad idea to put new seals in the oil cooler to save you some trouble down the road, if you already have it out and the engine is already 25 years old the seals could probably use freshening. I wouldn't worry about internals on an engine with miles that low but seals tend to dry up and leak over time and it is a good time to change them while you have it out. You might even want to throw a new water pump and thermostat in it to rule that trouble out down the road too. I hate to sound like I am "Spending your money for you", but these are all things that wear from age and not just use and it would be easiest to change them now. If you don't have the extra cash right now, then I wouldn't change all these things but it will be harder once the engine is in the truck again.

 

[Dirtleg]

Based on what you said I agree with Rldsl about the retarted timing. My advice on the transplant would be to look for seals and gaskets that are obviously leaking and fix those areas. Oil cooler as well just because it's a PITA later.

Good luck.

 

[oldmisterbill]

Especially the rear & front main seals.as siad all ready oil cooler ,Valve covers gaskets & grommets where the turbo mounts. My 2 bits

 

[Diesel JD]

Personally if I had to choose, I would do the head gaskets and the oil cooler orings. The rear and front main seals would be next. I bet the water pump and other stuff could go a few more miles. I'm not really aware of the history of your truck, but I suppose you have a bad motor in the newer truck, if so and you also have a good fuel system there it might be good to switch that over to the 6.9 especially if it was quiet and a little weak. That usually means retarded timing or maybe a fuel system that could use freshening. Turbo should be fine unless it has excessive play or oil leaks, personally cold side orings and grommets would be nice to replace though Gale Banks would probably charge you 100 bucks for a set just cause his name is on them. You could probably do just as well with a generic set of orings as long as you could match the sizes exactly. After all they're only sealing air not oil or coolant. Also if it's a K&N filter or similar that the turbo has now is a great time to wash it or buy an SB filter which I think might be a little better than the K&N based on the experience of the forum members here. However only a couple of us have used them so that may not actually be the case.

 

[TWeatherford]

Good advice, thanks. That's about what I was figuring, though I hadn't thought of oil cooler seals.

Even at this altitude I can't get this thing to smoke, so I'm guessing the pump hasn't been messed with. I'll get the pyro working and all the real gauged I need in my 94 and get it cranking a little more.

One thing I thought of: am I correct in gessing that the manual hubs on this 3/4 ton won't work on the Dana 60 on my 1 ton? It would be nice to have them if so for when the auto hubs go out.

It starts a little hard, I'm thinking its the return line because once it catches its fine, and restarts after that are instant. But wow, my starter on my other truck was way worn out, and my battery cables were also in sad shape, this one spins way faster.

 

[towcat]

my .02....
i would mess with the head gaskets if you are this far from home.
i have yet to see a set of 6.9 heads that haven't got cracks in them.
the cracks that go into the water jacket or cumbustion area are the fatal ones. you can easily make a benign crack a fatal one by loosening the head bolts. regasket and reseal the exterior and go with it.
btw, you may have some fitment issues with the Banks up pipes.
DDC and I found out that the hard way when I sold him a Banks kit off a 6.9 C6 and his truck has a ZF5

 

[Optikalillushun]

if they are hubs from a dana 50 they will work.