So I was told this engine was rebuilt 8,000 miles ago... after finding another complete 1.6L/8v motor I decided what the heck -- let's explore and off the head of the "rebuilt" motor....

Me not knowing what a rebuilt motor looks like -- do these cylinders look "rebuilt?"  My valves are covered in a thick oil paste too.....and the pistons have pretty good amount of movement... i can measure the side to side movement with a caliper when i get home.   surprisingly compression in all 4 cylinders is 180psi...so maybe the motor is good after all. 

Only reason I was taking it out is because it'll be easier to just drop in the other complete motor.

First - there's rebuilt and then there's rebuilt - and it all depends on whose doing the rebuilding.

You mention a "pretty good amount of sideways movement - I don't have a manual for the 8v engine but on the 16v the allowable piston/wall clearance is 0.0008~0.0015" - I don't think you should be seeing any movement that can be described as pretty good.

Last rebuild I did the clearance was on the very edge of acceptable, but with no wear ridge at the top and the machinist was telling me to just hone & "re-ring", but I opted for a rebore to first oversize - I'm pointing this out because either way that engine could have been described as "rebuilt", but the rebore will give longer life than the re-ring.

180 psi is considered good, but on an engine that is 8000 miles old, shouldn't it be higher?

Chiltons and haynes ( I ordered a fsm) shows 180psi as "where it should be"...if I recall correctly.

The motor I'm dropping in has 104k mileage and has 185-190psi compression. So you are probably right about higher compression.

The line on the top pic in the cylinder...that's not normal Is it?

Pretty good in this instance is pretty bad. Atleast I think ...

That doesn't look like a fresh quality rebuild too me. At 8k there should be no oil gunk anywhere. The rings will take a Lil bit to "seat" but long before 8k. It is hard to tell from photos on my phone but that score on the top photo and uneven ring wear on the second compiled with sludge would lead me to a shadetree hack rebuild job maybe.

Chiltons and haynes ( I ordered a fsm) shows 180psi as "where it should be"...if I recall correctly.

FSM for the 16v (sorry I don't have the 8v manual) shows 199psi as standard and 170 as miniumum - I don't think the 8v will be much different.

I agree with jluck - there is a bit too much crud on top of those pistons for an 8000 mile fresh rebuild

Tomorrow I'm pulling motors and transmissions. 3 weeks ago I only did carpentry projects...I never woulda thought I'd be doing this! If I knew I was going to swap ECM, wiring, and motors I woulda picked something like a 1.8L Audi...ha

In that top picture it looks like there is either a big score down that cylinder or a big crack, either way thats looks bad.

In that top picture it looks like there is either a big score down that cylinder or a big crack, either way thats looks bad.

thats kinda what i was thinking. that verticle line isnt right

I thought that line was to improve air flow...kinda like a cold air intake

I thought that line was to improve air flow...kinda like a cold air intake

ummm, unless it has reeds and you mix oil into the gas, no, it shouldnt have verticle passages

I forgot to put the ha jk....lol