I'm ready to fire my 400 after I rebuilt it. The last time this engine was cranked was 5 years ago. But I just finished rebuilding it with new bearings, rings, cam, HP oil pump, pump shaft, rebuilt head, and all new gaskets. Built to stock, except I added stock windage tray and HP Melling oil pump. I primed it about 3 or 4 months ago when it was still on the stand and a 3/8 drill wouldn't do anything so I switched to a 1/2" drill and it worked and showed good pressure on the gauge I had hooked to the oil pressure port. Now I've got the 400 in and everything hooked up and ready to fire. It has a good blue flame kernel and the engine turns over and sounds nice and healthy just like a big block Mopar sounds cranking. I don't have fuel in it because I wanted to re-prime it by cranking it and make sure it actually even cranks, which now I know it does. But is it going to register oil pressure on my mechanical gauge? I don't even see oil making it up through the tube or into the valve covers because I removed the cap and didn't see oil. Some mechanics I've talked to said it's going to have to be fired up to register oil pressure. I just now removed the oil filter and it flowed out a little stream of oil so I guess the pump is working. It wasn't totally full though. Is this normal to not see oil pressure register on the gauge when you're first cranking a rebuilt engine?

I think it will require a lot of cranking to get the oil up the tube. I guess you could prime the tube, but it's probably too late now to do that. Yank the distrib and re-prime it if you are worried about it. Fire it up and if it doesn't "read" w/in a few seconds you can always shut it off.

I pulled the plugs on my 440 thats from a MH and had been sitting a couple yrs

after a little bit of spinning I was getting a reading on the stock gauge as it spun over

poped the plugs in and fired it off,fired right up and did not clatter like most will do after sitting

I had done the spinning and no plugs a couple difftimes/days before ready to fire it off

you may or may not see it with a mech gauge

oil duz not have to reach all the way to mech guage to read

I have seen them with air pockets on the sb truck never had any troble with it

I say pull the plugs,spray WD40 in the cyls,spin it over a few times with short burst of the key

30-45 seconds at a time,should be ready if you have already primed it with a drill also

good luck on the fire up

Yeah that can be normal to not see oil pressure on the gauge. You should really prime oil pump right beofer you fire it... maybe a few hours before or so. If you can't prime the pump for whatever reason, you can pull the spark plugs out and crank the engine over. That will let it turn over way faster and get oil to the cam.

I'd stop turning it over like you have and prime the pump then fire it up for best results. Good luck!!

I guess it's time to just fire it up. I asked mechanics around here too and they said the same thing. Either way pulling the plugs now or pulling the distributor out is a pain. It's hard now to bring it to TDC on compression because the shroud and fan make it harder to get a socket on the crank pulley bolt. The plugs are going to be a pain to change on this car I know. It doesn't have any room left on the passenger side because it's a small block car.

I've changed oil/filter and cranked the eng w the ECU disabled until the psi came up which sometimes takes quite a few seconds. With all the turning over you have done so far I would consider taking off the intake and regooping the lobes/lifter bottoms.

I hate cranking a fresh rebuild v-over any more than nesessary. the more you crank it over the more it cleans the cam lube off the fresh camshaft and there seems to be an abundance of cam troubles without looking for it.

I'm also against cranking without fire.
As already mentioned, the cam lobes but also many parts of the engine are not lubed during cranking. The piston pins, rings, cylinder walls and usually the cam lobes are not lubed during cranking.

So should I re-prime with the drill and just fire it up? I pre-lubed everything really good while I was building the engine. I used Redline assembly lube. I used 10W-30 MAG 1 oil that has the ZDP additive already in it and I'm adding Redline Engine Break In additve. I can definitely re-prime it with the drill before we fire it up this coming weekend.

Repriming would not hurt, but I had starting problems with my fresh 440 rebuild one night and cranked the batteryalmost dead.After spending the next day of double checking everything, fuel, timing, new plugs, mine fired right up and has run fine for two years....