First start after build....low oil pressure light stays on!!!

[1.9TD Caddy]

Finally got my AAZ to start after complete rebuild build. The low oill pressure light stays on. I replaced the oil pressure switch on the side of the head. Still stays on. Removed the turbo oil feed line and it was bone dry.
I am pretty sure I had the oil pump correctly installed,
Does the system have to be primed? I will appreciate any ideas.

[libbydiesel]

What car?  What oil pressure warning system?  When you ground the pressure switch wire does the light go out?

[1.9TD Caddy]

The AAZ is installed in a 1981 caddy. The original engine was a 1.6D.

[1.9TD Caddy]

I will try grounding the oil switch in the morning to see if the light will go out.

[CRSMP5]

did you preprime the oil system??? 11 or 12mm socket on top of oil pump.. turn till oil pressure/resistance... just remove the vac pump to do this.. if you get no resistance you did something wrong..

you can do this with a drill or a old fashon speed wrench..

[1.9TD Caddy]

Ok. went out to garage and did the following.

Grounded the oil pressure switch...light stayed on.
primed the pump with a 11mm socket and drill.....after about a minute felt and saw oill sloshing around. Cracked open the oil line to the turbo....plenty of oil flowing.
The question is how much damage have a possibly done running the engine for 30 sec to 45 sec with the engine oil light on?
Thoughts and ideas will be much appreciated!!

[libbydiesel]

The oil pressure switch is either open or grounded.  If the light doesn't go out with the switch grounded then it is a wiring issue that is independent of the engine's oil pressure.  Likely you've had oil pressure all along and not done any damage to the engine. 

[wdkingery]

if the lifters are hydraulic, from my experience, they will collapse and the motor will stop running if it's not getting oil.. but that wasn't from a dry rebuild, it was from watching a tech not put oil back in a 3.0L V6 ford motor. this might take 30-45 seconds tho.  

i too had oil light after rebuild, but it was because i switched the wires from the temp sender and the oil pressure sensor on the side of the head during the reinstallation of the head.

i'd say if the motor didn't get to squallin, then it's probably alright.

The oil pressure switch is either open or grounded.  If the light doesn't go out with the switch grounded then it is a wiring issue that is independent of the engine's oil pressure.  Likely you've had oil pressure all along and not done any damage to the engine. 

^^ this

[1.9TD Caddy]

Thanks! all. Engine is running ok.