I have rebuilt my oil pump and have oil flow problems. Here is what i did: Cleaned inside of my engine (sorry photos were taken before cleaning) Put oil pump back in and bought an autometer oil pressure kit. I put in the oil pressure sender and set up a Ohm meter (did not have the gauge with me or a car battery). Results: I ran the oil pump with a cordless drill to prime the pump and am getting about (I think) 50psi (see chart) which seems good I am looking at the open engine (see photos) and I barely see oil coming out of the hydraulic lifter (they are out) holes in front of the engine. No flow in rear (near pump) and NO flow on the heads where the rockers are supposed to be. I am worried. I assumed I should see something flow. Conclusion: Do I have blocked oil passages ? (there was a lot of crud in my engine and I did not dismantle it further than in the pictures) Is 135Ohms not 50PSI and I have low oil pressure ? Did I miss something ? I did have some clicking noise when idling my engine. The rocker shafts are kind of marked: I therefore assume the heads were somewhat starved for oil. What should I do ? I cannot dismantle the engine further... Can I try to blow/inject acetone or thinner in the oil passages ? Is my engine fine and I have just been breathing too much paint thinner ? ou:
I called autometer and it seems my pressure would be around 32 PSI and not 50.... Bad/ good ? I tried understanding in the shop manual how the oil flows.... Do I need to turn the main crank for the oil to flow through the bearings to get to the rockers correctly ? Are there passages that open up at certain crank angles ? The book mentions stuff I dont quite understand ? Thanks for ANY help !
RJBT, Put the lifters back in the engine and see if you get oil up top and at the lifters at the back of the block. Pressure and oil will escape without the lifters in place. Cheryl
Yep, what Cheryl says..... the rocker shafts look good,,, the cleaned up rocker arm assemblies look good.... Without the lifters in place you cannot possibly have any oil pressure.... for a nailhead 50 psi on a cold engine is pretty much normal,, then it will drop to about 20 on a hot idle.... and when you rev it up the pressure will come up to 38-40 on a fully warmed up engine....the old rule is,,,, the engine should gain 10 psi for each 1000 rpm of engine speed....when it is fully warmed up,,, any more than that is just icing on the cake....
Maybe this will help. A picture can be worth a thousand............... Ok, just forget the clich and click here. Cheryl
Ignore the part in the last paragraph where it says the oil pump is located in the timing cover.....that's wrong! My 1966 Buick Chassis manual has an error....there are 2 paragraphs that describe the oil system of a different engine, not the nailhead.o No:
I finally put the hydraulic lifters back in and the rockers shafts (all cleaned up) and got the autometer gauge to work ! Problem: with my makita 1987 (oldy but still works well) cordless drill i only got 25 psi o No: I tried to get a normal drill in but it was too big. My drill must be going at around 500 to 800 rpm.. That should be enough to get normal pressure shouldn't it ? 25 psi seems low.... Should I attempt to start my engine or should I drop the oil pump again and check it over / change it ?
RJ,,,, when a engine is running the cam runs at 1/2 the crank speed.... and the dist runs at 1/2 the crank speed.... so the oil pump would be turning at a speed of 300 rpm at a normal idle speed [600 rpm]..... and on my nailheads that makes around 40 psi [cold] and 20 psi [hot]..... but when you rev it up some , cold, it goes up to 50 psi..... and to 40 hot..... You may not be getting as many rpm as you think from the drill motor,,, because a oil pump will positively drag it down.... my Makita has a time pulling the oil pump when the system primes up , on any engine that I build..... Are you getting a good supply of oil up to the rocker arms????? there should be a bunch ......
25 psi is enough pressure to run the engine at low/moderate engine speeds.....for testing purposes anyway. Hopefully, you'll have more pressure when the engine is running. Over 30 psi is preferred for normal driving.
Doc, OK I understand that the oil pump is going 1/2 the speed at the engine crank is. My drill is definitely having a hard time turning the oil pump once the oil primed (drill go really hot so I stopped) but I assumed that it at least got to 300rpm ... may be not. OK so i'll rebuild my carb and put everything back together and start it to see if I get a better pressure. When cold I assume i should get a minimal of 30 psi then ? Can I start the car without radiator, fan etc.. at least for a few minutes ? (until it starts to feel warm)
You do want to have the fan belt on to drive the water pump, and it should have water in it. Even 10-15 lbs of oil pressure is enough to run it while stopped. I wouldn't drive it unless it had over 20 lbs. If you're getting 30 with a drill, you should be fine!:TU:
Yeah !!! I finally got my engine started up again (after 9 months rebuilding carb, painting etc...). I reinstalled the oil pump and put a oil pressure sender in the block. I started her without a water pump so I only ran it for a few minutes. At idle here is the oil pressure. 25 lbs I revved it (not tach so clueless on RPM) and here is how high the gauge went (30 lbs ?)... Is this too low ? Is it fine ? Should I drop the oil pump and check it again for clearance / tighten it better (what are the torque settings ?) ? Or should I have it rebuilt (very hard to do here from France) ?
On a cold engine, at idle - choke on, I would expect to be getting 38 to 40. What oil are you running ?
I'm running a 10W40 basic mineral oil... Just for the startup after 9 months of sporadic cleaning. So my oil pressure is too low ? Dangerously low ? Or acceptably low (and can still do the job) ?
Sounds low to me. Fine for running in the garage and seeing what's up but I would want to see higher oil pressure before calling it a done deal.
Where should I have my pump rebuilt ? Or buy a new one (cant seem to find any) ? Or get a decent rebuild kit (what if clearance in the pump is bad ?) ? Any recommendations ?
Kanter, http://www.kanter.com///productdeta...0&Vdr=&Itm=&MDv=1&MDpt=0&MSb=0&Cat=32&Prc=358 They require a core for a rebuilt unit. But they may offer a do it yourself rebuilt kit. CARS Buick parts http://www.oldbuickparts.com/ I didn't see a pump or rebuild kit for yours, but it might be worth a shot to contact them
