Sick or Healthy? Where to start?

[SeanC]

Just stole a 1979 CJ5 w/ I6. The back ground info is she had been been sitting for awhile. New fuel pump and battery. Carb definitely needs rebuilt or replaced. Choke doesn't work but idles ok once warmed up. Noticed after about 5 min of running she smokes out the pvc pipe at the fire wall and from the tail pipe. I know it needs a full tune up - oil, coolant, etc. But with the smoke wheres the best place to start. Just looking to get it on the road for now but don't want to go out to soon and blow the engine. *also looks like last person bolted a newer (still old and leaking) exhaust cause I noticed an 02 sensor still mounted. Haven't looked for a cat yet. I will get more info in the am.

 

[Saddle Tramp]

Blue smoke = oil, white = coolant. I suspect you might have some blow-by at the PVC

 

[TeamRush]

The 'Professional' approach...

If you are seeing 'Smoke', the PCV is either not working,
Or the engine is producing more blow by than the system can handle.

The place to start to see if the engine is 'Healthy' is with a compression test, both wet and dry.

I would also do a leak down test,

I would most certainly check to see how much slop there is in the timing chain/timing set.

While I was there, I would VERIFY TDC of COMPRESSION stroke,
Then verify the balancer,
Then check to see if the distributor was still dropped on the camshaft in the correct location.

This is all pretty simple.
Find Compression Stroke MANUALLY, don't use the starter motor,
Find TDC of #1 piston on COMPRESSION stroke,
Have a look at the balancer, if the 'Hash' mark is at the ZERO mark, the balancer ring hasn't slipped around the hub,
Then mark the #1 plug wire terminal on the distributor base, Flip the cap, See if the rotor is pointing at the mark you made for #1 or not.

This would be the #1 FACTORY location, not where the wires landed from a Previous Owner (PO).

This will verify the harmonic balancer is mostly correct,
It will verify the plug wires/firing order are still factory (Timing chain hasn't jumped a tooth or two),
And will tell you if the camshaft timing is mostly where it needs to be.

And maybe check lift on the camshaft lobes, see what the valve train looks like,
Broken springs, bent/broken rockers, Valve Stem Seals, ect.
Just the cost of a valve cover gasket will tell you a TON about the engine...
Camshaft lift at the rocker/valve will tell you if the camshaft still has 'Lumps' or it's 'Round' when it shouldn't be,
Excessive buildup of carbon in the head will tell you the engine has been overheated/not had the oil changed regularly,
The gray 'Goop' inside the valve cover will tell you if there has been excessive moisture in the engine,
A 'Green' cast to the gray goop will tell you there has been a coolant leak at some point...

Compression DRY test will tell you if the cylinders are sealing up enough,
Compression WET test will tell you how much leakage you have around pistons/valves,
A leak down test will tell you how much wear there is in the cylinders/valves.