whats your oil pressure?

ok just as a poll kinda of thing ... to see where i stand.

at startup i have about 60psi
after about 5 min warm up it gos down to about 10 psi

at 45 mph i have 60 psi

normal ?

and i have an older guage with a tube filled with oil going to it.

 

Seems normal to me. I assume this is a 258? My 4.0 does the same and thats after I rebuilt it(maybe thats the problem ). I recall many others having similar issues with no ill effects. Isn't the old racers rule of thumb 10psi per every 1000rpm. So idling at 700rpm should only require 7psi. Luckily thats also during a no load situation. Obviously, more would be better.

Kevo

 

its a 304ci ... that meant if its 60 psi im at 6000 rpm ? i dont have a working tach ... i have one ... but i cant get it to work ...

 

my :v6: has 25psi @ idle (700rpm) and 40psi @ 2k.

 

I have about 50psi at start up, after shes warms up it drops to around 30psi at idle.

 

The AMC V8 can suffer from low oil pressure due to the oil pump running in the aluminum front timing cover. It's common for high mileage AMC V8s to have only a few psi pressure at hot idle. The housing wears out and the oil pressure goes way low at hot idle. High mileage AMC V8s are known for spinning rod bearings, and the tendency to low oil pressure doesn't help.

The first place to look is the gauge. The original gauges are notoriously inaccurate. Get an aftermarket mechanical gauge and check the actual hot-idle pressure. <edit> Looks like you have an aftermarket gauge.

If the pressure is really 10psi at hot idle, you should first refurbish or replace the oil pump cover, oil pump gears, and timing cover. You can MEASURE the wear of the gears - here's a good article: http://www.jedi.com/obiwan/jeep/wagoneer/401/timingcover.html ... the article refers to quality control problems with the aftermarket timing covers. The supplier claims that these have been fixed.

After you MEASURE the pump clearances, and they are within spec, and you've dressed the oil pump cover and replaced the gears, if you still have low idle oil pressure, you then need to look to the condition of the rest of the engine.

IMO 10psi at hot idle is marginal. A NEW AMC V8 should see about 25-30psi at idle.

 

60 at start-up, 20 at idle, around 60 at 3000rpm

 

AMC 258, 800 miles since rebuild. Cold start 60-75 PSI, Hot idle 25 PSI. Cruise 50-60 PSI.

 

ive allways gone with the 10 psi for evry 1000 rpm rule and havent had a problem. as allready mentioned, amc motors are notorious for crappy oil presure, the 360 i just put in my jeep idles hot pretty low, 10 psi or less if i recall . because the motor had sat for four years, it is now leaking from some of the seals bad enough to put a litre of oil every couple/three weeks, so every now and then i add a litre of 20/50w and that seems to help with the psi situation