Couple Quick Questions!

I've got a 1969 Nova that I recently built my first engine for and installed it. Everything seems fine except for two things... when the engines cold, it's oil pressure is at about 60 psi but once it gets up to temperature, the pressure drops to 10 psi at idle and around 20 psi at cruising speed and 40 psi when you really get on it. All of this SEEMS low to me, but i might be wrong. The other thing is I've ALWAYS got roller rocker arms "clacking" at idle but when i get the rpm's up to about 1,200, the clacking goes away. Is this due to a few lifters going bad, or is this due to the low oil pressure at idle? and If it is due to the oil pressure, is it doing any harm? or is this normal for having hydraulic lifters with roller rockers? well thank you to anyone that can help! I appriciate it!

I would start out with getting another oil pressure guage and geting a second reading.
When you first start it cold are the lifters ticking/clacking? How did you adjust your rockers? You may need to re-adjust.
What kind of oil are you using?

yes the lifters clack when its cold and i got the lifter finger tight and then did a half turn and im using, i think, a 30 weight oil.

yes the lifters clack when its cold and i got the lifter finger tight and then did a half turn and im using, i think, a 30 weight oil.

When your setting your lifters are you setting them all at the same time like that or in sequence and rolling the engine 180 and doing the rest?
Half of them get adjusted at TDC on the compression stroke and the other half 180 deg. on the crank.

oil pressure sounds low is bearing tolerances in limits

i use a remote starter to turn engine and adjust them in sequence according to the position of the cam and the firing order. I think i got this part right because the car runs fine and doesn't back fire or anything. The only noticeable thing that seems to have to do with this is the idle is kind of "loppy" although the car has a mild cam in it. It kinda of sounds like everytime a certian few cylinders fire, those cylinders are louder and blow more exaust than all the others.

Typical process used for the older engines to adjust rocker arms was to run engine until it was warm, remove valve cover, use a piece of stiff card board as an oil deflector below the valve springs, restart engine, adjust each rocker completely one at a time as follows:

Slowly back off adjustment nut until the lifter starts to clatter. Start tightening just until the clatter stops. Tighten the nut a 1/4 turn at a time till you reach 3/4 turn, allowing the lifter a few seconds between turns to adjust its oil volume. When the engine smooths out, go to the next rocker. This adjustment proceedure allows for optimum valve opening and lifter operation. Static adjustment is just comes close.

Did you replace the oil pump? You should have. If you did, was it a pressure pump or high volume pump? Makes all the difference.

when you built your motor did you put new parts in? If not it could be a worn cam bad bearings or lifters. I have a 75 nova i lost oil pressure when it was cold it would run 50 psi at idle, as it got warm it would slowly go drop to 40 then 20 then idle at 0 psi, no noise other than the big cam i had in it. After it would get to tem after running it hard it wouldn't ilde. I tore it apart and found that my lifters ten out of sixteen had came apart, the keepers in the top where the push rod sits all broke (comp lifters) i had pieces all in the motor i had to replace the crank bearings lifters. what happens is the lifters can't pump oil because they aren't going all of the way in. if i was you and love your car the way i do take the intake off and check your lifters or chance it, but it will cost you in the long run if you don't.

k well i DO have a high volume pump and i though maybe that was it, its pumping alot of oil just not alot of pressure so my oil pressures low but idk if thats how all high volume pumps are or if i need to get a different pump or wat. but also i took my intake off and pulled out my lifters and some of them are so stiff i cant pump them with all my body weight and some of them were compressed and loose and would rattle if u shake it so im gunna order new lifters and try that out and see if it raises my pressure and if not ill try putting in a normal oil pump or a high pressure pump. one more question, when i pulled my lifters out, i could only get six out by hand and the other ten wouldnt come out even with pliers... so do u have any advice on how to get those out?

You definitly need new lifters. They should all be filled with oil and pumped up. New lifters will have nothing to do with increasing oil pressure, but your rattle will go away as the lifters that rattle when you shake them are shot.

You will need to bleed the new lifters and pump them up prior to installation. You do this by putting clean oil in a small can and stand the lifter up in the can. Make sure the oil comes over the top of the lifter so it doesn't suck air. Then you take a brass rod or phillips screwdriver and press all the way down on the center plunger. As you release this pressure, the lifter will fill itself with oil. Repeat the process until the lifter is full typically 1 or 2 times is suffecient.

The lifters that are stuck in the bores have a ring of varnish built up at the bottom of the bore. You need to keep working them up and down and twisting them until you cut/scrape the varnish off the bottom. Be patient!!!
Avoid trying to put solvents on the lifters as they will dilute the oil in the galleys and might score the lifter bores on start up.

High volume oil pumps are OK. They run lower pressures at idle normally. The pressures increase with engine rpm.

Sounds to me like one or more of the oil gallery plugs at the front of the block are missing.

We NEVER use a high volume pump in anything but a 400...

Jim

Did you have this lifter rattle before the rebuild? Did the rattle stert just after the rebuild?

Galley plugs could be the problem, but it is rare in stock engines. I could see it with a high pressure pump. Not as likley with a high volume. I have seen this just one time back in 1970 with a small block Ford. This is why racers thread the block and put in pipe plugs in galley holes and welch plug ( freeze plug ) holes.

The timing cover and cam gear would have to be removed to discover and repair this problem. There should be 2 small plugs on each side and just below the cam shaft.

There is another way to prime your lifters, I took a old distributor pulled the gear from the bottom of it took everything off of the top. And welded a socket to the top of the shaft, Put all your lifters in the block install the distributor use a air ratchet tool and run it until all lifters are oiling now they are primed.:smokin: :smokin: . Now to get the other lifters out you can turn over the motor by the crank pulley it might be hard and you will have to put it back in time 2. Now when you prime the lifters this way you will need to put the intake back on but it won't need to be bolted down at this time, take your valve covers off and make sure the push rods are in.

i got the block when i bought the car and i built the block with new lifters so i never heard it before but the engine isnt stock. I put inall the galley pugs and freeze plugs and i dont think i missed any but if i did would i still have 10 psi at idle and 20psi at 2,000rpm? also i took out a couple more lifters and i took apart a broken one and it looks like the plunger got jammed up when it got pushed down. i dont know if this is because i used an electric drill to prime the engine and not all the lifters got oil or if this is because something in my oil is jammin them up, like from my bearings. but i think im going to go ahead and get some new lifters and prime each one by hand so i know they all get oil, put it all back together, and out new oil in it and see what happens. and if it happens again then maybe ill need to check my bearing wear. But thank you guys for trying to help me, i really appriciate it.

I've been building engines for 40 years and have always primed lifters before installation. Never had one fail yet.

You should have no less than 20 psi at idle and 35 to 45 psi. at 2000 RPM. At these pressures it would be easy to loose lifter prime. You still have a serious oil flow problem. I feel you are dumping it internally somewhere.

I think that you might have gotten a bunch of bad lifters, it has happen to me. put some new lifters in and i bet your problem goes away.:grinyes: :grinyes:

I think that you might have gotten a bunch of bad lifters, it has happen to me. put some new lifters in and i bet your problem goes away.:grinyes: :grinyes: so when this happend to you and u put new lifters in your engine did that fix your oil pressure problem?? because my lifters were DEFINITLY broken, they just didnt come apart they got jammed down.

Lifters will not increase or lessen oil pressure. They will only affect the circulation to the top side of the engine. Once you have totally collapsed a lifter without proper lubrication, it will self destruct. A lifter should never rattle.

Lifters will not increase or lessen oil pressure. They will only affect the circulation to the top side of the engine. Once you have totally collapsed a lifter without proper lubrication, it will self destruct. A lifter should never rattle. alright well i went ahead and ordered new lifters so ill install them and then from there, handle the oil pressure problem.