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Discussion Starter #1
I've just rebuilt the engine in my '79 Spider. After cranking it for a good 30-45 seconds, I get no oil pressure on the guage. Thinking the gauge sender was bad, I substituted another. Same thing. There's no oil drips on the back of the sender either, leading me to believe that the pressure is not building up. The oil pump is a new one, and yes, there's oil in the pan. I've never had a car take longer than this to build up pressure, so I think something's wrong. I know the oil pump is turning - the distributor is turning and its run by the pump. What am I missing here? Thanks!
 

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Hmm. Just found this on the internet, is this true? If so, I guess I shouldn't worry about 0 oil pressure when cranking, but still, I've never had a car do this before after a rebuild. Perhaps it's just the location of the sending unit. Again, this is my first Alfa rebuild. Let me know if it's true:

It is normal for the cars to show strong, nearly constant oil pressure when cold, and then have very variable oil pressure when warmed up. It is normal for a warm 2.0L engine to show zero oil pressure at idle on the gauge. It is not normal for the car to show zero oil pressure on the gauge and have the oil pressure light (top right red light on a Series 2 car… just to the right of the gauge) activate, or show pressures substantially less than 57 psi (usually half way on the gauge) at highway cruise speeds. Beware also of cars whose oil pressure drops off quickly regardless of temperature, or that never reach roughly the middle of the gauge. This problem is expensive and difficult to fix (although, maddeningly, the parts to fix it only cost about $5.00).

From ALFA SPIDER FAQ
 

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I hope you assembled the engine and squirted some assembly lube on all bearing surfaces.

Try cranking some more (spark plugs out) and see if you can get the pump primed. Otherwise you may have to manually prime it. I can't remember the procedure for manually priming after the engine is assembled, but maybe papajam does.
 

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Yeah, I moly'ed everything real good. I squirted oil in the pump during assembly, but that was a while ago, so it's likely drained out. I should have put in vaseline or something, but I've never done that before, so I didn't think of it here. Hmm, if I pull the oil filter, maybe I can squirt oil into the pump passages from there? Which hole if so?
 

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Thanks guys. I pulled the plugs and cranked away - still no pressure reading on the gauge. However, when I unscrewed the filter, oil pours out, so it must be primed enough to pump through the filter (I think), right? That 20-50 oil is pretty thick and it's only 55 degrees out.

Now I just need to find the ignition sweet spot and get the darn thing to fire.
 

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In my experience, it IS normal for V6 (164s especially) Alfas to show very little to zero oil pressure at idle when hot, but *NOT* normal for the 4 cylinder cars to do this.

My GTV shows approximately 15 psi hot @ idle. Something is up with either the gauge or the sender if you don't show any oil pressure at idle. I have also seen new senders that don't register pressure at idle, just because it's new doesn't mean it's a good sender.
 

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Are you getting any oil in the cam area? If you're pretty sure you're getting some oil pumped from the oil pump, I think you're pretty safe in going ahead and starting it. The assembly lube should protect the bearings for an initial start.

As far as oil pressure in 4 cylinders go, in the summer my engine with 90k on it shows only about 10 psi at idle when hot. Running, it's about 50-60 psi. The gauges arent' super accurate, but the important point is that the oil pressure idiot light isn't on at idle. The oil pressure idiot light is set to 5 psi.
 

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If the oil pressure light goes out when cranking, there's enough pressure to start the engine. If the gauge still reads zero after engine start up, I'd shut down the engine and hook up a mechanical oil pressure gauge to confirm pressure (or not). Did the gauge work before the rebuild?
As far as I know, since the pump is geared to the crank, there is no manual priming procedure after engine assembly other than to crank the engine with the sparkplugs removed. The only engines I recall that required packing the pump with grease were Buicks.
None of the Alfa engines I've built have had a 'lost prime' problem including a 1300 that sat in a corner for ten years before it was installed!
Oh, stupid question. Were the crankplugs installed?
 

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For what it's worth, I was very concerned with the lack of oil pressure when cranking my 1969 1750 GTV. The oil pressure light didn't come on however. It turned out the guage was sticking. I would start the car, the guage showed 0 pressure, I flick the guage face with my finger and the needle would bounce up!.

Ken
 

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GTV4EVR said:
.... It turned out the guage was sticking. I would start the car, the guage showed 0 pressure, I flick the guage face with my finger and the needle would bounce up!.

Ken
Good 'ol Alfa (or is it BMW) reliability, eh?

Welcome aboard Ken!
 
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