Pulled a 1987 out of a hole

captain720

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Should I do a red neck leakdown with an air compressor next or should I buy one of these? What’s a good next troubleshooting step?

 

Nero

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Compression test will tell us a lot about the health of the engine.
 

captain720

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Compression test will tell us a lot about the health of the engine.
Considering that it came out of the ground and I know it was an ether baby before I would like to know. Is the HF tester “good enough”? I think at this point I am more looking for a dead hole more than 99.9% accuracy.
 

Black dawg

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If the valve train looks good, pinpointing cylinders would be next. Another thought I had, if it seemed like it was running on all 8, but just wasnt right, is headgasket between cylinders.

Can you post a video of cranking with FSS wire disconnected?
 

Nero

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Considering that it came out of the ground and I know it was an ether baby before I would like to know. Is the HF tester “good enough”? I think at this point I am more looking for a dead hole more than 99.9% accuracy.
From what I've read is ether destroys the precups on the heads, and in general can break a ring. Breaking a ring most likely won't cause it to chuff like it is.

I'd still start with compression testing, because if that one hole is way off, or really close in reading to the rest of the holes, it'll tell us if it's a compression issue or something else.
 

Rdnck84_03

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From what I've read is ether destroys the precups on the heads, and in general can break a ring. Breaking a ring most likely won't cause it to chuff like it is.

I'd still start with compression testing, because if that one hole is way off, or really close in reading to the rest of the holes, it'll tell us if it's a compression issue or something else.
Is it possible it is compression from broken rings coming up through the cdr? This was why I ask about blowby from oil cap, compression in crankcase should be seen out the oil fill every time that cylinder comes up on compression.
If the valve train looks good, pinpointing cylinders would be next. Another thought I had, if it seemed like it was running on all 8, but just wasnt right, is headgasket between cylinders.

Can you post a video of cranking with FSS wire disconnected?
This is also very possible.

I would pull the oil cap and spin it over before spending money on the compression tester to rule out compression into crankcase.

If there is compression from oil cap that would most likely mean some sort of piston damage.

If no compression from oil cap I would try blowing air into each cylinder with valves closed.

If there is one cylinder that blows back to the intake, I would lean towards valve.

If two cylinders next to each other blow to intake or exhaust, I would say head gasket.

This is my thoughts, which may not be worth much, (I am what most call a shade tree mechanic) so feel free to let me know if any advice I give is counter productive.

James
 

Nero

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@Rdnck84_03 if you have a broken ring, crankcase venting will be uneven. I actually used that as a diagnostic step when working on my dad's truck with engine#1. Pulled oil fill, and it had a very obvious chuff out the oil fill that was an exhaust looking color. Grayish. But only did it like it was one cylinder doing it.

Checked my truck, and it was essentially a smooth stream of gasses coming out of the oil fill.

Pulled my dad's engine, and turned out the engine was dusted and had a broken ring. Hone marks essentially non-existant.
 

captain720

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I will get a video of the valve train moving. Nothing real obvious coming out of oil fill so far just the normal bit of steam or whatever at a steady rate.
 

captain720

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looks like a head gasket between cylinders, plan is to pull the motor so I am ordering this.

 

IDIBRONCO

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looks like a head gasket between cylinders,
That's my guess too. If you plan to turbo it in the future, now would be the time to install head studs too. Not that I'm trying to spend your money, but you'll already be at the point that you could install them.
 

captain720

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That's my guess too. If you plan to turbo it in the future, now would be the time to install head studs too. Not that I'm trying to spend your money, but you'll already be at the point that you could install them.
Yes that is the plan, arp studs from CDD I am also paying for an E40D rebuild on the psd so I wanted to wait a minute before ordering the studs.

Engine is almost out just stopped for a dinner break.
 

captain720

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This thing is heavy, I need a bigger stand so I had to go the old tire on the ground route.

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