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No Oil Pressure.
Had some oil pressure problems with my 421 s.b.c. that I race. Just happened to look at the guage and it read 0 psi. we wound up putting a new filter on, the pressure came back. Couple weeks later the same thing, and we put another filter on, the pressure stayed below 5 psi. Pulled the distributor, looked at the tangs comming off the oil pump, they looked fine, put the distributor back in, fired it up for the hell of it and wound up with 35 psi.
Some of my friends suggest the pick-up tube broke off the pump, one says i spun a cam bearing. Just wondering if this has happened to any of you. I did also try a new guage. In a few weeks im going to pull the motor and see exactly what the problem is.

Did you cut the filters open to see if they collapsed? Do you have a bypass in it or is it removed?

Hi Pro, No I havent taken the filter off yet. I only had a few mintes to look at the car for the first time this spring, now we're getting another Blizzard up here in Minnesota today.
In a week or so I'll take the filter off and cut it open. I have been using WIX filters lately. I was thinking , if the pickup broke off the oil pump and I had low or little oil pressure, if I added an additional 2 qts' of oil and the pressure came up that would suggest the pickup broke off. I suppose at any rate we will pull the motor, as I have to have these heads flow tested because we feel we didnt the the H.P. numbers on the dyno that we expected from this small block.
Thanks for the suggestions, I appreciate it.

Welcome, Mr. Monte. These guys will get you fixed up... bp

Thank you Draglist. As I mentioned, I will pull the motor to confirm what eaxctly happened, but it's interesting to hear different opinions, I've learned a lot that way. This motor only has about 10 pulls on the dyno and about 30 passes at the track. I do drive it on the street once in awhile also.
We are going to flow test the heads and go with a different cam, possibly smaller and hopefully make more h.p. We were shooting for 650 and only hiy 609. In the meantime I appreciate any and all suggestions.
I'll take the filter apart in the next week or so. Thanks again guys.

probably not related to your problem, but this happened to me a few years back......

I would crank my motor up (at the time a .060 over 460 BBF) but my oil pressure gauge was very slow about coming up. Sometimes, I would tap the gauge and the pressure would jump up to the 60 or so lbs that was normal for that bullet.....so....rocket scientist me, figured that the gauge was junk.
I changed out gauges, but was greeted with the same issue.....no oil pressure. Still thinking that the gauge was the problem, I took off to a track that is about 150 miles from my place......as I was unloading the car, my eyes were glued to the oil pressure needle......it never wavered or shimmied. I shut 'er down and got some help pushing the car back up on the trailer, and became a spectator for the remainder of the evening.
The next day, I did a bunch more checking and, after removing the pan and the pump, discovered that the oil pump shaft was spinning in the gear.....whenever I would first crank it up, that 50 wt LUCAS that I was running was causing the gear to not turn and the shaft to freewheel inside of it until the oil thinned a bit......that never took very long, but any time without oil pressure is NOT a good thing. What aggravated me the most, though, was the fact that that was a brand spanking NEW Melling Oil Pump.............I dug my old pump out from under a work table, took it all apart and made sure everything was clean, put it back in my motor and am still using it, even in my new 514 stroker motor.
Good Luck with yours!!

Thanks Billy Mac. All kinds of funny things happen. It will be interesting to pull the pan and look at everything. We just got hit with a blizzard and made the national news ( Duluth Minnesota ) so it'll be awhile before I can get the car out of storage and over here to my garrage. I will let you guys know what i find tho. Thanks again.

O.K. just to let all you guys know what happened. The pick-up tube stayed in tact, The "basket" fractured the metal in 2 places and was laying on the botom of the pan.
This was a&%##% assembly. I understand they have a "heavy duty" assembly. I will order that along with a new oil pump as long as we have the pan off.
My intention her is not to place any blame on any manufacturer but rather to inform their R.& D. dept as to what is happening with thier assemblies as this has happened with at LEAST 3 motors this year.

Sorry for the problem but glad you caught the problem before time became......

glad you found the problem