1984 Turbo GL Wagon 116K miles, off the road since 1997 (hard to believe that is 25 years ago)

After sorting distributor issues and new injectors it is running

Compression 1,2,3 Cylinders 150 psi #4 130 psi

Oil Pressure with a not new but not trashed Oil Pump and new 10w30 at 50 ambient temp startup 40 psi Oil Pressure dropping down to between 10 and 12 Psi at Idle when fully warmed up.

Thinking it may have a rod knock, piston ring broken or lifter not pumping up based on Oil Pressure readings and engine noise.

Looking for opinions on source of noise see video

 

 

 

Sounds just like EA82 lifter playing up after either sitting for years or need replacing. I even get this on new EA82 lifters, reco lifters and a low speed drive lurking around suburbs has taken 20 minutes to go quiet. It also sounds like when I pulled a Ford six apart to find a broken comp ring. I wonder if the sound can be isolated to the one with lower compression ?

EA82 early turbo are only supposed to be 120 warm comp test. I have a later with 150. Surprised you getting 150 from an EA81T . NA seem to vary 170-190

Grab a long screw driver, put the handle against your ear and start touching the engine all over to find where the knock is coming from.

I have a few running EA81T longblocks, if you need a replacement.

Congrats it runs!  Hard to tell.  After 25 years those hydraulic adjusters could be seized or not pumped up.

What does an EA81 do if the HLA is collapsed or offers excessive clearance?  There might be potential for significantly more noise than typical HLA tapping. 
In EA82/ER27's if the HLA gets too weak or collapsed the rocker arm falls off. 

That video sounds like a harsh knock but between the accuracy of a recording and my hearing I'm unsure. 

5 hours ago, idosubaru said:

That video sounds like a harsh knock but between the accuracy of a recording and my hearing I'm unsure. 

Yes, I agree.  The recording quality is too low to be able to be sure what it is.  I have a sound systems hooked up to my computers.

After reading your post, I played the video through my cars audio for a better listen. Hard to say, it sounds a lot like mine did and I drove it for years and over 80,000 fairly abusive miles that way. Lol.

Yours does seem a little harsher than mine, and I didn't have any forced induction. Maybe try for a better recording if possible? Some of these more guys here that are more experienced than myself could probably give you more info with that. 

If I had to pick one, personally I'd say worn or insufficiently lubricated lifters.

Cut the oil filter and look for metal. 

The consistency of the sound suggests a lifter. Rod knocks tend to sound inconsistent with engine RPM. 

GD