I'm going to try and fire my zero mile fresh rebuild up this weekend. It's a 1982 12A in my 1985 GSL. I removed the beehive and now have an aftermarket 10 row FMOC with an Earls external oil thermostat.

The engine has brand new NOS rotor housings, bearings, and all seals.

Question: Do I need to fill the FMOC will oil before I fire the engine up? The oil thermostat has a bypass until the oil gets up to temp (around 140F I believe). Once it opens up, my fear is that it will lower the oil level in the pan. I added additional oil temp and oil pressure gauges just to keep tabs on everything.

 

I usually disable fuel/ignition, and crank it over for a little bit to prime the oil system, I wouldnt be too concerned about oil level drop when the t-stat opens. If you fill it up with the proper amount of oil, the level should be fine once everything opens up and fills. but if you are really worried about it, you could fill up the oil cooler as well, the only down side about doin that, is spillage when you fill it or install it in the car

 

+1 and I was going to add if you're pre mixing try a break in oil , like torco's or sumthin .
And I usually start a motor on old plugs because they usually either flood or foul out unless you get lucky.
I switch plugs after the smoke clears from assembly lube and whatnot

I prime oil first, then fuel, then brap brap grump,vrroooom

 

I usually fill the lines and cooler so I don't have to spin it as long to get oil pressure.

 

I was thinking the same thing. With a bigger FMOC, my fear is that without filling the FMOC it would rob the pan of oil. Here is my setup. Have have since made up -10AN hoses. I was just going to remove the upper hose and use a hand pump to fill it with oil.

 

just crank it without plugs* until it has oil pressure, check the oil, fill as needed, put plugs in, enable the ignition and enjoy


* engine cranks over faster with no plugs, AND you get to blow out all the assembly oil/grease/vaseline/spiders(you said NOS) etc.

 

I found a dead spider in an oil pan once. The engine sat for a while.