Ok after a lot of playing I finaly got my new motor to run it seems to run ok I still have some carb problems but it dosnt leak oil so im happy, but im a little worried about my oil psi. at idle my guage only shows about 15-20 psi and 55-60 at 4000 rpm and up my old motor had a constant 60-75. when I did the motor swap I added a fmoc and got rid of the beehive could this cause lower oil pressure? should i be worried or is this ok.

 

Your oil pressures are on the low side factory specs, both at idle and 4k. You might consider modifying the ropr or picking up the 85psi RB one. The other option is replacing the oil pump. The old one may suffice as opposed to buying a new one.

The low oil pressure may also indicate that the clearances between the e-shaft and bearings are near thier limit. Did you use the old sending unit, or the one that was on the newer engine? Try the old sender and see if the readings change.

 

What type and weight of oil are you using?

 

10w40

 

In summertime, I usually go with Castrol 20/50. But that probably isn't the issue. I just wanted to make sure you weren't using some super lightweight synthetic or something.

 

Make sure you oil level is ok

maybe you just added the same amount of oil you used to use before the front mount and now you are low

 

thats what i was thinking^^^

 

no oil level is ok I filled the cooler before putting the lines on. at first used 10w30 but then after running the motor for about 5min i changed to 10w40 this made no change. then this morning i drove the car to work and when i got about 1 block away the psi droped to about 5 psi and wont go any higher. i found no leaks but it was about half qt low.

 

Is it running fine otherwise?

And you are useing the stock in dash guage?

My stock guage does crazy **** on a regular basis. I never worry about it.


Are you useing the pressure sender from your old motor or one that came stuck in your new motor?

 

is it blowing any smoke?
i never knew the psi on the oil because the 79 it came from had no oil pressure gauge.
we dove the car around for a month with no problems, alex 7 can verify that.
the previous owner said it smoked on a couple occasions but i assumed it was from a stuck seal or something.
you might want to try driving the **** out of it and see if that loosens something up.
---adam

 

Seafoam and run the **** out of it. (not that it probably has anything to do with a pressure problem, but because any motor thats been sitting needs a beating)

Make shure there is nothing funky going on with the pressure sender check the reading with a real guage if you get the oppertunity.

These motors are not prone to oil pressure issues in any of my experiance. If it's running fine I wouldn't worry.

 

might not be a good idea to run the **** out of it until your can pinpoint why exactly your not getting proper oil pressure.

but on another note someone should get some readings off a properly running sender so he he could check his.

 

well I just went out after work and started it and the guage didnt move I have never had problems with the guage before but as for the sending unit I cant say for shure I had like 5 of them laying around i just grabbed the best looking one. I hope that is it. It dose smoke but I think its just the carb otherwise it runs ok. im running home to grab another oil pressure guage and another sending unit so wish me luck. thanks for the info Ill let you guys know what i come up with.

 

well i changed sending units and I have pressure again. it stays between 30 and 60 psi what numbers do you guys get I tryed to put on an aftermarket guage but i dont have the proper fitting so i guess ill have to stick with what i got for now.

 

mine drops way low when I don't give any throttle and maxes out at around 60 at wot

 

You can drill/tap the banjo bolt at the rear of the engine, to put an aftermarket mechanical gauge in. You can also order a banjo bolt from mazda that is already drilled/tapped. That was needed to test the oil pressure in a '79.........
On my car, the OP stays around 30 at idle, 60 at highway RPM, and closer to 90 on the track.