Thread: Oil Plug

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ok guys got another question. Is there a plug under the rear main bearing cap on a BBC like on a SBC to route the oil to the filter? I am actually fighting my motor right now and noticed a pretty good drop in oil pressure once it gets warm. Starts at about 60psi cold with 10w-30, once it is warm it runs about 45psi off idle, but drops significantly at idle. It is running a high volume/std pressure pump. Seems a little low to me, but I am also used to a high pressure/high volume pump in a SBC that puts out 60psi warm. So did I miss something or am I gonna need to put a high pressure spring in the pump to get the pressure I want?
Thanks,
Clay

what makes you think you need more then 45 hot were is the mains and rods at for size if you have a std oil pump did you set up the oil pump end play? a loose botom end you are going to be at 45 .there is no steel cup under the main cap like a sbc the older bbc s do not oil like a sbc i do not run 10w30 in any of the bbc s for race use. i have had bbc s that were very loose like 10 hot at idle and 50 past idle for many years as long as the oil psi builds when your getting on it your ok if you move up to a 40wt oil just make sure that the oil has some temp to it before you get in to it

Thanks Pat, that makes me feel a little better, did not realize BBC were so much different then a SBC on so many things. 45 hot is about 1500RPMS and higher, at idle it runs about 15. I was told to run the 10w-30 along with ZDDP plus for camshaft break-in. I was planning on using rotella 15w-40 once it is broken in. I had to shut it off 2 times trying to break it in before I gave up on it till I get back from instructor school. Had a water leak the first time, and it started to get hot the second time so I shut it off. After I shut it off the lower hose came off, the 1 clamp I guess I missed double checking. Runs like a scalded ape, just been a real pain. I am actually sitting in class on break right now. Want to get everything in order so that I can get it all knocked out when I get home and get it dropped in.
Thanks again,
Clay

Then mains were .020 undersized and the rods were .020 undersized when I pulled the motor apart. The machine shop did a quick polish the make sure there were no burrs on the bearing surfaces. The bottom end is a little looser then it normally would be. I do not recall the actual numbers cause I am not at home with all the paperwork. Do you think I will have a problem once parts start to wear-in and should I switch to a high volume/high pressure pump to combat this or just run it and address it when/if it ever becomes a problem?

well the pump it self can be loose as well not pumping as good or bottom plate of oil pump not flat from bad finsh and leaking i lap them in with 220 and wd 40. pump may not be setting on the cap flat leaking the new blocks gm spot faced the block for a Oring thats the oil hole that runs from the oil pump thru the main cap they can leak here as the finsh is so choppy all this could add up .i break every thing in with 30wt has for your zinc you need to watch the oil you use as the detergente in oils has gone way up and will blocks the zinc from working .the detergente block s the zinc from working in to the part. did you try another oil psi gauge .yes you could go hv oil pump but if your loose like003 mains and rods. i would think your goining to be about were your that for psi. for the break in i use the joe gibbs or brad penn that way i know it should have the rigth zddp pack and it all works together with no or very low detergent .i have been told that adding more zddp to hi detergents will not help the zddp. lake speed from joe gibs said if there any detergent oil that the zddp will not work hard to say if its all zddp or some there not that many that make the stuff . so i pay abit more for break in oil

have not tried another guage. The one i am using is an equus mechanical guage. lucky for me I am breaking it in on a makeshift stand out of the jeep so if something goes bad during break-in i dont have to pull it back out.
Clay