Iam currently working on rebuilding this motor but i would like to clear up some of my concerns.

I drove my car to my dads witch is around 50-60 miles from where i live. then stayed the night.

I had Started the car early that day to move it then it was shut off.
after it had set for about an hour it decided it did not want to run.
had spark and fuel so i ran compression and came up with this 80|100|150|65.

I then Put a little oil in each cylinder through spark plugs came up with 150|125|160|90

Then i decided to try to put a little more in each cylinder to see if it would run since it tried to start after previous compression test.

Walah! it started. I drove it out of the garage up and down the drive way and down the street and back.
came back in because it sounded like a cylinder doped.
Sure enough the first cylinder i checked had 25 psi in it.

I pulled the head today there are no burnt valves, cams have no wear, barley any oil deposits. (42,XXX on the motor and head just bought and doped it in about two months ago.)
timing belt is new and was put on before i bought the motor, along with the water pump.

cylinders are smooth throughout.
no etching
no marks on pistons
pistons looked clean

head gasket does not appear to have anything wrong with it.

oil smells like gas and had smoke from dipstick and valve cover.
i am having the head checked to see if it is the culprit for compression loss.
i am going to replace rings and head gasket .
i have also ordered new 1.8 pistons since i was going to do that soon anyway as well.

if you think i am missing something in my analysis

 

you need new piston rings my friend. if its not the head, its your piston rings.. have fun

 

see i understand where you coming from and i obvously think the same thing.
but it ran fine the day before how the hell could that be.
Rings went out over night?

btw; already taken the steps necessary to rebuild the motor.

 

when you were performing the compression test, did you crank it at least 5 times and have the pedal at WOT? The readings will be eratic if you don't do those things... If this is the case, then you may be troubleshooting the wrong thing.

 

I'd say rings as well

 

Oil rings, Compression rings, or in internet geek terms,piston rings.

Get new piston rings and ye worries will be not, do compression test

Post back

Edit
The only thing the oil is doing is probably filling the air gaps causing good compression which really isnt
then after it runs, the compression goes back to normal.

Does it go through alot of oil?

and like said above, crank engine a few times manually after doing your little oil drop test
then try again

 

It might not go through much oil, especially if the oil change interval is kept short. I bet the oil is nasty though. And it runs like @ss when it does run.

Yes that little bit of oil from crank windage could be making enough of a compression seal to let the engine start and run but it will feel like a brand. new. car. when you finally get the rebuild done.

And my pet concept: Don't forget to put Singh grooves in the head! I bet they keep you from having to increase the grade of gasoline you need with the 1.8L pistons.

edit: oh I forgot, it's possible the rings went bad-enough finally, just during the last drive, but I would want a bore gauge down the cylinders because they need to rub against SOMETHING to wear out. I also recommend you take the chance to lap the valves to their seats but that's another bunch of work.

 

what do mean by lap the valves.

 

If the valves are not mating properly with their seats, they will not seal right and compression may be lost through the closed valve.

Lapping is a process of using extremely fine abrasive slurry (valve lapping compound) and rotating each valve's face against its seat. It is a poor man's valve job, and can correct very minor imperfections in the valve seal.

 

i had the head compression tested an all seals are good so i don't have to worry about that.