How important is priming the oil pump? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

chevy72blu · 12-03-2007, 07:26 PM

Because my BBC is installed so far back, It would be impossible to remove the dizzy completely and prime the oil pump. I assembled the motor over a year ago with a high grade assembly lube on everything. Could I not just splash some oil on top of the heads, and crank the motor w/o ignition to allow the oil pump to do the work on its own before firing it? I'd really rather not have to pull the motor - but I will if I need to.

Thanks

airdale94 · 12-03-2007, 07:37 PM

That's the whole purpose of assembly lube is to provide lubrication on initial startup. I personally wouldn't worry about it. I've rebuilt several engines and have never primed the oil pump. All you are really doing by priming the oil pump is shooting some oil up to the rocker arms. The crank and rod bearings shuld have assy. lube on them anyway. As with cam bearings, lobes, and cylinder walls. The only pumps that actually need to be primed are external dry sump and you pack those with petroleum jelly to prime them.

I would just double check your intial timing, prime the carb. and fire it up.

oldspowered67C10 · 12-03-2007, 07:37 PM

I think that would be sufficient.

jim zag · 12-03-2007, 07:47 PM

If you can not remove the distributor and use a oil pump priming tool and a drill then fill the oil filter and oil pan, remove the spark plugs, and spin the engine over until you get oil pressure.

chevy72blu · 12-03-2007, 07:58 PM

Good, thanks for the info guys. I appreciate it.

How does one check initial timing without the motor running? Im still hoping and praying that I stabbed the dizzy in the right location.

BCOWANWHEELS · 12-03-2007, 08:29 PM

i dont see why you cant pull the dist. ?

chevy72blu · 12-04-2007, 01:13 PM

Because I installed the motor as far back as possible for weight transfer and the lip of the firewall is above the distributor.

crazy longhorn · 12-04-2007, 04:06 PM

Remove the cap & rotor.....you should be able to pull the dist.

stllookn · 12-04-2007, 04:22 PM

Chances are that you did not "stab" the dizzy in the correct location to begin with unless you were EXTREMELY careful, were at true TDC on #1, had the dizzy body correctly positioned and had the rotor positioned on #1 (after it rotates 15 degrees when the gear engages the cam). Good Luck.

Wrenchbender Ret · 12-04-2007, 04:28 PM

I have an old fire extinguisher I put a tire valve in the side & a hose on the outlet. I fill it with oil & pressurise it. I hook the hose into the opening for the oil sender unit & squeeze the handle putting pressure to the oil gallery.
I think you can get by with filling the filter up with oil & cranking the engine with the plugs out or ign disconnected.

67_C-30 · 12-04-2007, 07:46 PM

If you can't prime the oil pump, I'd take out the plugs and take off the coil wire and and free spin a little with the starter before actually cranking it. It would allow the oiling system to prime without having any of the stress of compression.

*Billla* · 12-04-2007, 10:36 PM

IMHO, I wouldn't fire anything that's been sitting without pre-oiling. I agree that if all you can do is pull the plugs and turn it over, I would STILL do that vs. nothing at all.

Easy check on the distributor - if you're at TDC compression #1 the rotor should be pointing directly at the #1 spark plug tower

You're generally looking for around 12 BTDC for initial startup.

496stroker1 · 12-04-2007, 10:51 PM

had a cam go flat on me with my first big block chevy bout 5 years ago, probably cause the engine spun over too much before it started.

if space is tight how about using a right angle air drill with an oil pump primer

12-03-2007, 07:37 PM	#2
airdale94 Registered User Join Date: Jan 2007 Location: Topeka,KS Posts: 778	Re: How important is priming the oil pump? That's the whole purpose of assembly lube is to provide lubrication on initial startup. I personally wouldn't worry about it. I've rebuilt several engines and have never primed the oil pump. All you are really doing by priming the oil pump is shooting some oil up to the rocker arms. The crank and rod bearings shuld have assy. lube on them anyway. As with cam bearings, lobes, and cylinder walls. The only pumps that actually need to be primed are external dry sump and you pack those with petroleum jelly to prime them. I would just double check your intial timing, prime the carb. and fire it up. Last edited by airdale94; 12-03-2007 at 07:40 PM. Reason: add

12-03-2007, 07:37 PM	#3
oldspowered67C10 Registered User Join Date: Jan 2006 Location: Cherry Valley,Ca Posts: 468	Re: How important is priming the oil pump? I think that would be sufficient.

12-03-2007, 07:47 PM	#4
jim zag ENGINE BUILDER Join Date: Apr 2006 Location: Shortsville n.y. Posts: 344	Re: How important is priming the oil pump? If you can not remove the distributor and use a oil pump priming tool and a drill then fill the oil filter and oil pan, remove the spark plugs, and spin the engine over until you get oil pressure. __________________ JIM ZAG

12-03-2007, 07:58 PM	#5
chevy72blu Registered User Join Date: Apr 2004 Location: Las Vegas, NV Posts: 2,188	Re: How important is priming the oil pump? Good, thanks for the info guys. I appreciate it. How does one check initial timing without the motor running? Im still hoping and praying that I stabbed the dizzy in the right location. __________________ RIP EastSideLowLife '72 C20 SWB convert. 5 lug, LS1/4l60e

12-03-2007, 08:29 PM	#6
BCOWANWHEELS Registered User Join Date: Nov 2006 Location: KINGSPORT,TN. Posts: 3,035	Re: How important is priming the oil pump? i dont see why you cant pull the dist. ? __________________ I BELIEVE IN JOHN 3:16

12-03-2007, 07:26 PM	#1
chevy72blu Registered User Join Date: Apr 2004 Location: Las Vegas, NV Posts: 2,188	How important is priming the oil pump? Because my BBC is installed so far back, It would be impossible to remove the dizzy completely and prime the oil pump. I assembled the motor over a year ago with a high grade assembly lube on everything. Could I not just splash some oil on top of the heads, and crank the motor w/o ignition to allow the oil pump to do the work on its own before firing it? I'd really rather not have to pull the motor - but I will if I need to. Thanks __________________ RIP EastSideLowLife '72 C20 SWB convert. 5 lug, LS1/4l60e Last edited by chevy72blu; 12-03-2007 at 07:26 PM.

12-04-2007, 01:13 PM	#7
chevy72blu Registered User Join Date: Apr 2004 Location: Las Vegas, NV Posts: 2,188	Re: How important is priming the oil pump? Because I installed the motor as far back as possible for weight transfer and the lip of the firewall is above the distributor. __________________ RIP EastSideLowLife '72 C20 SWB convert. 5 lug, LS1/4l60e

12-04-2007, 04:06 PM	#8
crazy longhorn Fabricate till you "puke" Join Date: Jun 2002 Location: Ill Posts: 9,402	Re: How important is priming the oil pump? Remove the cap & rotor.....you should be able to pull the dist. __________________ 69 longhorn,4" chop,3/5 drop, 1/2 ton suspension/disc brakes,1 1/2" body drop,steel tilt clip, 5.3/Edelbrock rpm intake/600 carb, Hooker streetrod shorties,2 1/2" exhaust/ H pipe/50's Flows , 6 spd Richmond trans,12 bolt/ 3.40 gears....

12-04-2007, 04:22 PM	#9
stllookn Saving 1 truck at a time! Join Date: Aug 2001 Location: Kent, WA Posts: 6,465	Re: How important is priming the oil pump? Chances are that you did not "stab" the dizzy in the correct location to begin with unless you were EXTREMELY careful, were at true TDC on #1, had the dizzy body correctly positioned and had the rotor positioned on #1 (after it rotates 15 degrees when the gear engages the cam). Good Luck. __________________ '68 C20 Longhorn 50th Anniversary 400/TH400 '68 C20 Longhorn 50th Anniversary 468/TH400w/buckets '72 C20 Halfhorn (Longhorn w/o cab and front clip) '69 Flxible Cruiser (look up ugly in the dictionary)

12-04-2007, 04:28 PM	#10
Wrenchbender Ret Registered User Join Date: Oct 2005 Location: Overland Park, Ks. Posts: 5,229	Re: How important is priming the oil pump? I have an old fire extinguisher I put a tire valve in the side & a hose on the outlet. I fill it with oil & pressurise it. I hook the hose into the opening for the oil sender unit & squeeze the handle putting pressure to the oil gallery. I think you can get by with filling the filter up with oil & cranking the engine with the plugs out or ign disconnected.

12-04-2007, 07:46 PM	#11
67_C-30 I have a radical idea! Join Date: Jan 2005 Location: Sweet Home Alabama! Posts: 6,513	Re: How important is priming the oil pump? If you can't prime the oil pump, I'd take out the plugs and take off the coil wire and and free spin a little with the starter before actually cranking it. It would allow the oiling system to prime without having any of the stress of compression. __________________ '67 C-30 Dually Pickup 6.2 Turbo Diesel, NP435 ‘72 C-10 SWB , 350 4bbl, TH350 '69 C-10 SWB , 250 L6, 3 OTT '69 GMC C3500, dump truck, 351 V6, NP435 '84 M1009 CUCV Military Blazer 67 C-30 Turbodiesel build thread http://67-72chevytrucks.com/vboard/s...d.php?t=254096 My trucks http://s226.photobucket.com/albums/d...ediafilter=all Member of the 1-Ton Club!

12-04-2007, 10:36 PM	#12
Billla Account Suspended Join Date: Sep 2005 Location: Monroe, WA Posts: 3,814	Re: How important is priming the oil pump? IMHO, I wouldn't fire anything that's been sitting without pre-oiling. I agree that if all you can do is pull the plugs and turn it over, I would STILL do that vs. nothing at all. Easy check on the distributor - if you're at TDC compression #1 the rotor should be pointing directly at the #1 spark plug tower You're generally looking for around 12 BTDC for initial startup.

12-04-2007, 10:51 PM	#13
496stroker1 Registered User Join Date: Nov 2007 Location: brooks alberta Posts: 65	Re: How important is priming the oil pump? had a cam go flat on me with my first big block chevy bout 5 years ago, probably cause the engine spun over too much before it started. if space is tight how about using a right angle air drill with an oil pump primer



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