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Dvldog 8793
07-30-2004, 05:39
Howdy
As everyone probably knows I'm in the process of a new long block. Is there a good way to pump up some oil pressure in these motors prior to initial startup? In the gassers that I've done in the past I always ran the pump with a drill until I built up oil pressure. I did this through the distributer hole. It doesn't look like this is possible with this motor?
I know I could always turn the motor over without the glows inplace to at least limit the amount of pressure on the bearings but I was hoping to get good oil through out the system prior to start up.

Thanks in advance!
L8r
Conley

Mainous
07-30-2004, 06:38
Do it the same way as you always have. The gear drive soes nothing on the new motrs but connect the cam to the oil pump. Pull it out, use the drill, and put it back. No timing to worry about just drop it in.

JohnC
07-30-2004, 06:44
If the engine is recently assembled with enough assembly fluid, it shouldn't require pre-lubing. However, it's better to get the oil filter and galleries filled before hand, and ascertain that the pressure lube system is working before starting, rather than taking the chance that you'll find out after you start it that it's not working. Easiest way is to crank it over with the starter with either the injectors or glow plugs out.

If you feel the need to prelube, put a couple of quarts of oil in an old freon can. Pump the can up to about 20 psi with an air hose and plumb the tank into the oil pressure switch port. Invert the can and open the valve. The air pressure will force the oil into the engine. Shut the valve before the air starts coming out...

99gmccrew
07-30-2004, 07:24
I'm putting a long block 460 in my boat today. The instructions said to turn over the engine for at least 2 minutes without any plugs in and watch oil pressure gauge to verify that is getting pressure. Once pressure is established go ahead and start motor and run it at 1800 rpms for 15 minutes. I'm not sure if it would be the same for a diesel.

tom.mcinerney
07-30-2004, 18:12
With due respect to Mainous ["The gear drive soes nothing on the new motrs but connect the cam to the oil pump"] I found on my '95 block that a socket on the pump shaft (drillmotor-driven) provided enough press to flood the crank bearings, and the drvrs side cam followers, but left the psgr side followers and turbo feed (not to mention rocker-arms!) dry.

I got a spare 6.5 oil pump drive , ground off the gear teeth , hacksawed off most of the top aluminum cap, ground 3 flats spaced 120 degrees to accept drill chuck (lost the needle bearings on the shaft), and was able to then establish decent oil pressure throughout the block (also flooded valley/bellhouse vicinity with a half gallon lube). So maybe John C's plan is easier!

If patient/desperate i can send my 'primer', as i won't use it this month...

Dvldog 8793
07-30-2004, 18:56
Lots of good ideas....
I'm thinking along the lines of John C. Only I think I'll use an old fire extinguisher with oil as thats what I have and I should still be able get the pressure up there. Maybe I'll do a little of both. All I know for sure is that I don't feel right turning the key on a new motor if it's dry!
Thanks guys
I should be getting the long block Monday, I'll keep posting....
Conley

99gmccrew
07-31-2004, 07:20
Devildog, I have the same year 6.5 as you. I'm just curious as to what happened to your engine that would cause you to replace the block. Was it just normal wear and tear (high milage) or some type of factory defect. Thanks, just trying to avoid any pitfalls.

Dvldog 8793
07-31-2004, 08:20
99gmccrew-
check my other posts. It ain't pretty! :mad:
By all indications my block was the best one that General Motors used. The new ones are supposed to be better yet??? :confused: