Today I with the help of CyberBuick installed kick ass Auto meter gauges. After completing the install we fired up the car. Cold engine 1000 rpms had 15 psi. Reved the motor up to 2000 rpm and it jumped to 20 psi. (Slowly but Surely) Drove it for about two miles and got to a red light . I looked down at the gauge and saw 4 psi. I nearly @#$# myself. My question is obvious? Please help im at a complete loss on what to do. Oil is 10w30 and I have fram filter. (Wich will be changed to an AC Delco by morning.) Once again help! BTW it's a 1971 350 Ivan o No: o No: o No: o No: o No: o No: o No: o No: o No: o No: o No: o No: o No: o No: o No:
Hmmm... I assume the block was tanked? Perhaps the oil pump is bad. I've heard of Fram filters causing oil preassure problems, I don't believe they would be that bad.
Block was tanked. Assuming the oil pump is bad how would I rebuild it? or can I just buy another? Ivan
Allright after searching the forum and reading past advice. I have decided too change my oil pump gears and to get a booster plate. Would anyone recomend something different? Ivan:Comp:
Ivan, How does the engine sound? Any lifter or bearing noise? I would check the relief valve and spring. They are located behind the big nut on the filter housing/cover. The valve could be stuck open or the spring collapsed. If not, get a rebuild kit, and disassemble the pump paying special attention to the clearances. The TA Performance(TA1704) oil pump shim kit is a good idea. Is the gauge electrical or mechanical? If electrical, I would check the sending unit. It could be that simple.
Start by ditching the junker Fram filter, use either Delco or NAPA Gold/Wix, they work and don't drop pressure. 30 wgt oil is good for the Los Angeles area weather. Check oil pump gear end play, too much will cause the oil to bypass the gears and kill pressure. I'd install a tadpole relief valve in place of the stock one as well. How is the oil pump cavity condition around the gears?
I get a small amount of lifter noise other than that it sounds allright with the exception of higher rpm's. It sounds like it is starving for oil. And yes it is a mechanical gauge with the copper line.:TU: Ivan
Dave I will ditch the scam filter ooops I mean Fram. What is a tadpole relief valve? And where can I get one? I have'nt check the gears will do so before I rebuild anything. Im on my way to further investigate. Ivan :eek2:
Messed around with it a bit and still the same if not worst. Changed the filter to an AC Delco, Oil is Quaker State straight 30. Adjusted the spacing in the pump gears. Started out fine got it to go to about 38 psi at 3000 rpm's. After getting hot the pressure dropped back down to 1 psi idle at 600. When I leave it in park it idles at 1000 rpm with 10-12 psi hot. Cruising around at about 2000 rpm's I get about 20 psi hot . Im going to look for a stock pressure relief spring and switch that out. Ivan:ball:
I know what your going through Ivan, I too have dealt with oil pressure problems in a fresh 71 350. When you built the motor did you replace the timing cover? If not, there's a good chance this is what is causing the problem. TA makes excellent replacements or you can get a GM one for a little cheaper, or an aftermarket one for cheaper still. I would recomend the TA or GM as they will likely give more exact tolerances. New stock gears with a booster plate and adjustable pressure regulator is the best set-up. The pressure regulator has no effect on idle pressure but an adjustable one allows you to tune the amount of pressure increase as rpm's increase. Also, what kind of lifters are you using? Some aftermarket buick lifters are undersized from stock which causes pressure drop due to increased clearance in the lifter bore. Anyways hope this help, good luck.
Thanks for the reply Regal. To answer your question I did not replace the timing cover and dont know what kind of lifters were used. I have to try and track down where I put all my receipts for the engine work. I do recall that the timing cover looked good when it was installed but it was so long ago. I know TA sells a complete setup but I would rather go with GM or soomething with a better price range. Im going to try a few more things next weekend with an adjustable valve setup and thrust plate. Ivan
Quick follow up. I went ahead and ordered a TA Performance adjustable Oil pressure regulator. After the removing my old setup I noticed that the spring that was originally in my pump was about a 1/2 inch shorter. I installed the TA and after the first startup I saw great results im a happy camper. My pressure at cold idle jumped to 45 psi. I dont think I ever saw pressure past 32 psi. Anyways I drove it home about twenty six miles from my shop. At 1000 rpm's I was getting a good 20 psi and at 2000 I was at 35 psi. Im rreally happy I got this problem solved. Thanks Scott and Dave for all your help.:beer Also running hot in drive I idle at 700 rpms and am seing 12 psi. I have not messed around with the adjustable set screw as of yet. I want to get some feedback too see if you guys think this is good enough pressure? Thanks Ivan Gomez :Comp:
Ivan, With a small block, all you need is 10 psi/1000RPM. Looks like you have that. See what your pressure is at 3000 RPM hot. If you have 40-55 psi, I would leave it alone.
Definitely replace the timing cover. This is the weakest link in the oiling system.. at least for the 350. Any scratching or wear at all on the face plate is definite trouble. As far as oil pressure, sounds like you got it licked. Mine is 100 psi when cold. 75 psi under normal driving conditions and 25 at idle. Believe me it took alot of tweeking to get this. Your good though, believe it or not, there is a 10-15 psi pressure difference between the actual bearings and the oil pump. There is actually a procedure to drill a pressure gauge hole in the back of the block. In the installation procedure it talks about this psi difference between the pump and the bearings.
100PSI cold?? Whoa, that's high. I'd be afraid of wearing out dist. and cam drive gears. Well, that's because I have been there myself!
Yeah I have heard that running really high oil pressure is not good. I feel pretty good where I am at. I have also read that if on a buick you are seeing 10 psi per 1000 rpm's your looking pretty good. I am actually seeing about 15-16 psi per 1000 rpm. Ivan
GS Collector, From your post about your oil pressure, I have to ask,when is the last time you pulled your distributer and had a look at the gear? Your pressure sounds a little high :eek2: If you pull the Dist. and the gear is worn;very sharp edges,all isn't lost. You can get an adjustable reg. from TA.,Change oil weight and if it's really bad,worn cam gear on 350's you can change them without pulling the cam:Smarty:
