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blurat
08-20-2007, 09:31 AM
Hi, I got my 401 running yesterday , just for 2 minutes or so. I noticed the oil pressure at an idle was reading about 12 psi. I tried to search the forum for an answer but no luck. If this question is redundant ..sorry.
I have not been able to really warm the engine up as I dont have the interior done yet and there is no throttle. I have to let go of the trottle at the carb and run around to the guage and look.
The motor is full roller valve train and I used the valley oil rerout hose.

Thanks, b

blurat
08-21-2007, 08:38 AM
Let me rephrase the question.....what is a normal oil pressure range for the AMC motor?
b

Big Bad AMX
08-21-2007, 01:27 PM
Here's a thread you may find useful: http://www.amx-perience.com/AmericanMotorsForum/showthread.php?t=316

"An ideal AMC V-8 should hold 20-25 pounds of pressure at hot idle and 60-65 pounds above 3,500 rpms. Please note that when these engines were new in the 1960s/1970s THEY DID! This is on 10W30 oil."

Sounds like yours is pretty low. Max pressure is 80 pounds. Make sure you've got a good gauge before getting too deep into it.


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blurat
08-21-2007, 03:07 PM
Thanks for the reply.....interesting link, just what I was searching for. If I have to tear my engine down because the machine shop is less than prudent with their specs, I will just blow a vessel.
When I was putting the pistons in the block I stopped with the first one and next day went to the shop and mentioned the rods seemed awfully loose and got reconciled with "Thats the way we like to make em, they oil better"
Maybe I can find an 8 under bearing.
b

blurat
08-22-2007, 09:26 PM
K, today I ran the motor with a remote gauge screwed in. Just idled it and got zero oil pressure. Pulld the distributor and ran a drill on the pump. Still zero and as I was about to stop after about 30 or 45 seconds I got pressure. The drill ran it up to 40 psi so I put the dizzy back in and refired. Got lil less than 20 at idle...prox 600 rpm and when I revved it up it went right to 45 psi and no higher.
Im not too concerned with the press stopping at 45 as it can be a relief or bypass but what would cause the drain at shutoff and the delay picking up the oil. I did run the engine with the oil pressure line to the guage off and no oil came out the hole.. Still trying not to tear down the motor.
I have the bulltear oil pump cover with a remote filter. I wonder if the filter is too high and it causes the oil to drain back into the pan and I have a weak pickup, maybe too much end clearance at the gears.
Im takin the cover off tommorrow as it is 102 in my garage and im freakin dyin out there.
b

blurat
08-26-2007, 02:25 PM
Done, oil takes longer to pick up because of the 2 lines.
Changed the oil filter to a Wix 1515 with anti drainback valve.
Put a new gasket on my end plate at the pump, known to be 8.5k thick. Tore the other taking it apart so I am not sure of the measurement . Reprimed, fired motor and get 33 lb at idle. If it stays primed over night then I can move on to the interior.
b