401 oil pressure drop

[dagazio]

I thought I'd update my situation. I decided to bypass the dash meter after reviewing my setup. The wire from the sensor was cracked, making intermittent connection and I measure the resistance of the sensor which looked to be off quite a bit. It was reading 80 ohms across it when the engine was off and the wire disconnected, where I believe it should be 240 ohms. With that said, I shouldn't read low psi ever, but the open wire could cause it.

Therefore I decided to install a mechanical gauge, just to see what that said. After it warned up, it looked to have about 7 psi, in gear. It's low, but I think my motor won't spin a bearing. The pressure jumps right up with the rpm. I'm running Autozone 20W50 and a Fram filter. After reading a post elsewhere, I decided I'll probably change to an AC Delco filter and try another brand of oil, Castrol. I decided the filter might make a difference because the Fram is 18 micron vs the Delco at 25 micron and should offer less resistance, which will mean less pressure drop through the filter. I'm not sure about the oil, but I'll do one at a time to see the difference.


I also would like to do the first mod mentioned here:
http://www.planethoustonamx.com/main...stem_mod_1.JPG

I'll try to remember to post my results. Good, bad or ugly.

[acofficer]

So the timing cover did nothing. Motor pulled and new bearings going in.

[tufcj]

Be sure to check/change the cam bearings. I've seen probably 50% of the high mileage engines I've rebuilt with the coating flaking off the factory cam bearings. It has a bigger effect than rod/main bearings, since the AMC oil path oils the cam first. You might try Bulltear's bearings with the reduced size oil hole. I'm running a set of those in my AMX 390 with good results.

Bob
tufcj

[tarior]

X2. Absolutely change the cam bearings.

[Blown7]

BTW for what it's worth I had a old 304 years ago that ran 0-5lbs pressure at idle on a mechanical gauge years ago that ran for years.Never did blow that engine just retired it.

[dagazio]

Okay, I got my Delco filter and installed it. I'm not driving the car, so I can't tell how it's running under load at speed. I did get it good and hot. I really couldn't see a difference. It might have been 1 psi higher in gear, hot. I would say there was nearly no difference between the Fram and Delco filters in my engine. I'm not going to try a different brand (Castrol) of oil until it needs a change.