I have this issue with my 455 that I notice just while changing the valve steam seals. While doing this procedure I noticed like 4 valves are showing signs of wear due to lack of lubrication so decided to start the engine without the valve covers and see what was going on there. After 4 minutes idling I started seeing a bit of oil on some valve springs and after 10 minutos on all valves but it's just too little to consider it a good lubrication. The engine doesn't has lifter or valves noise, has never been rebuilt, oil pressure idling is 9-10 PSI @600 RPM I was expecting to do some mess while doing this procedure but the oil that was oiling the rockers was so small that almost no mess happened What should I be looking for?
If it is a 455, it oils from the lifter plunger cup, up the push rods, and onto the rockers. Look for a block somewhere. I'd look at the push rods. They should be hollow and open.
If I take the push rods out and blow air through them I can see oil coming out but still not good enough oil flow to rockers
The lifters have a hole in the plunger cup. Oil from the lifter goes up the push rod. Before 1970, the engines oiled the valve train through a passageway in the block and heads. Those engines used different lifters and solid push rods.
9-10 psi isn't going to produce a ton of oil to the top. How many miles on the engine? I would consider rebuilding the oil pump. You are at the bare minimum for pressure. How much pressure do you have on a rev?
"I" would re-test at 2000 rpm. Check oil pressure, check volume at rockers. Both should increase markedly. If it does, look at improving oil pressure at idle. If it doesn't...pull the engine. One begins to wonder about oil pickup screen being plugged with debris, and all the various oil issues these engines are known for.
Despite what everyone here says about Buicks and oil pressure, I still consider 9-10psi at idle alarmingly low. If my Pontiac 455 ever dropped below 30psi at hot idle I'd start getting concerned, and at 25 I'd be parking it until it was fixed. At 9-10 I would not expect to see much oil up top, and I also wouldn't expect it to last all that long, to be honest.
Yet Denny Manner, when asked what normal hot idle oil pressure was on a 455, replied, "anything above zero" I was there, and I heard him say it. Having said that, I'd be somewhat uncomfortable with it that low, but if it was 65-70 at 5500 RPM, I think the engine wouldn't be in any jeopardy. My first engine got as low as 13-14 psi, and I made many passes with that engine before I sold it. As far as I know that engine is still alive and kicking. My current engine makes 21-22 psi plus, and I never worry about it. Breathe on the gas and the pressure jumps up really quick.
Already checked the pickup screen and is completely clean. At @600 I have something between 9 - 11 PSI hot idling (Cold idling is like 30PSI at that RPM), up to 2000 RPM I have like 45-50 PSI and anything above that RPM passes the mark of 55 PSI
I've got the Exact same problem Jose and mine idles at 50 psi. Checked Push Rods and they're clean and clear. I'll drop pan next. 47k when I put it in last Nov, 48 now, but sat for 30 years. Did you figure it out? Thanks Mart
I'm having similar issues at 600rpm cold idle I'm around 45-50psi hot idle I'm 8-10psi. At around 2000rpm it goes to 25psi. I had it out in the hwy tonight 70mph 3000rpm and could only get it to 30 psi, if I hammered the gas it wouldn't go up anymore? Sorry not trying to hijack the thread.
What kind of gauges are you running? Mechanical,Electric,Old,New,Cheap,Expensive.Same goes for oil&filter.
30 psi at 3000 RPM is low. I certainly would not be hammering on it like that. Try turning the pressure regulator in. You want it to make around 70 psi cold.
Could just be a worn out oil pump or timing case cover like Joe alluded to. Do we know how many miles are on the engine? Pick up screen could be clogged with plastic timing chain teeth too right? .
I have newer sunpro gauges, fram oil filter and royal purple oil. The oil pump, timing cover(proform), chain and gears are all 3 years old. The motor was rebuilt 3 years ago with probably not more than 3000 miles on it. The car itself only has 21000 miles on it. I wasn't beating on it just giving it a shot to see if the pressure would climb. How far in do you suggest turning it in Larry? It does have the plate on it too. Just another bit of info is I think I may have a small leak at the rear main seal, I need to drop the flywheel cover to see. I also have not dropped the oil pan to check the pickup screen.
If the motor was rebuilt 3 years ago, chances are there isn't a nylon tipped timing gear in it. I can't see there being anything blocking the pick up either unless someone left something in the pan when the motor was assembled, unlikely. Cold, the engine should easily make 65-70 psi. Crank that regulator in a turn at a time and see if it reacts. Set it so you easily make 70 psi even at a cold 1200 RPM. Fram filters are the absolute worse filter on the market, and I have not heard good things about Royal Purple.
Well I did what you said Larry and I turned it in. I got it at 75psi at cold 1200rpm and the adjustment screw is flush with the lock nut. Should I back it off a hair to get it back to an even 70@1200? I will be changing the oil and filter again soon it was all I could get at the time. Besides the Joe Gibbs oil (which is hard for me to get) what other brand would you recommend?
