My 83 GL threw a rod and I picked up an EA81 just like the one that finally quit on me. It has 50,000 original miles on it but it has been in a barn for 25 years. My question is, besides resealing it and replacing everything rubber what else would I need to do to get this motor back in action? Should I replace the components with the ones that were in service a few weeks ago? That’s the original alternator I’d like to use it. 

Thanks

Break at least two of the inlet manifold to head bolts, usually outer one each side and replace inlet manifold gaskets with genuine .

Replace genuine hose between block and inlet below carby

 

Nice cradle !!

Edited May 5, 20205 yr by Step-a-toe

My thoughts as well. 
 

Read that as - be sure you have patience and a drill and easy-out kit , thread repair could be in the picture too , and better or new bolts. 
 

But to me you should use your existing intake and as mentioned above get fresh gaskets. 
 

Try soaking those intake bolts super well and for some time not just the few seconds before turning. And as often it should be done turn IN first. You know the drill , don’t have to tell you that stuff. Right ? Little back n forth and maybe you’ll get lucky. But I’d expect corrosion deluxe. 

Another thing I have found that helps avoid snapping those old bolts - heat the entire block up to near normal operating temperature.  It's aluminum so it is very hard to heat just an area.   It took a good space heater and a heat gun.  but it makes a big difference.  When I have a run able engine to deal with those bolts, or head bolts, I just run it.  I have removed some VERY stuck bolts using this, and not broken one since I discovered this trick.

18 hours ago, DaveT said:

Another thing I have found that helps avoid snapping those old bolts - heat the entire block up to near normal operating temperature.  It's aluminum so it is very hard to heat just an area.   It took a good space heater and a heat gun.  but it makes a big difference.  When I have a run able engine to deal with those bolts, or head bolts, I just run it.  I have removed some VERY stuck bolts using this, and not broken one since I discovered this trick.

also if they're really bad, on the intake bolts - loosen them slowly.  at first you may even need to tighten it a few degrees to get a range of motion to work it back and forth just a small amount.  if they're tight at all, work it back and forth 20, 45, or 90 degrees or whatever feels allowable and stop and go work on something else (another intake bolt).  the instant that resistance is felt, it starts generating heat.  it's localized heat not in places of advantage.  that's bad an expands and contributes to the issue. 

continue to work the bolt back and forth, and take many breaks along the way to allow it to cool down.  over time you'll be able to expand how far you're working it back and forth and the threads eventually begin to act like taps, cutting their way through the garbage. back and forth multiple times and eventually it's range of motion expands.

the corrosion ranges all the way down the shaft, through the thick intake manifold body, and into the head, and i haven't seen penetrating oil be able to get down far enough to help get started.  if you can get the head to come up at all and create a gap for penetrant access then get some down there, it's better than nothing and will eventually speed up the above processes referenced. 

 

Edited May 6, 20205 yr by idosubaru

Yes, this + heating the engine.  I got one of those out - it would have snapped right off if I had tried to just unscrew it.

 

The engine was stored without the intake manifold and there is Almost no rust or corrosion anywhere. The previous owner said he squirted some oil on the cylinders a couple decades back to keep rust down. Should I stick with 10w-30 or maybe use a detergent type oil for the first 1000 miles? 

10W-40 unless you are in extreme cold climate.

Well, I was right on suggesting new inlet gaskets

Seller was on the ball pulling manifold !

9 hours ago, Olyroller83GL said:

The engine was stored without the intake manifold and there is Almost no rust or corrosion anywhere. The previous owner said he squirted some oil on the cylinders a couple decades back to keep rust down. Should I stick with 10w-30 or maybe use a detergent type oil for the first 1000 miles? 

Just give it oil, no special treatments needed. Change the first one after 1k