Bill4224

i need to know what normal oil preshure would be for my car, i just installed a 90 motor in my 87, and it worked!! woohoo!!
anyway when i first started up the motor the preshure went up to about 100 stayed there for a couple of sec's then went to 60 for a min or 2 then went to 30 where it stays i have found that it goes up a bit when reving, but haven't taken it for a test drive yet (i am about to).
i just thought for a mazda reman block with only 600 mi on it. it should have higher oil preshure.

could some one tell me if this is normal and if i'm just being paranoid?

thanks

Scott 89t2

30 at idle is perfect. the 100 at start up is higher then stock. they should only hit 75. do you have an upgraded oil bypass or is it a stock engine?

Bill4224

ok here is the deal, when i turn on the car the preshure slowly goes up to just under sixty soon as it hits that point it drops, if i rev the car i can slow the droping but it will keep droping till it gets under the 30 and then lower it seems to drop al the way to 0 but i really can't tell, even if i rev it won't go back up, even if i am driving.....won't go back up.....
what could cause this?
i am about to install an after market gauge and sender to check if its a wrong reading....will this help???

copandengr

The first thing to do is make sure the gauge is accurate. If it is and you are getting near zero pressure at idle and no more than 35 or so at higher engine speeds then you have more than likely blown the o ring between the front engine cover and the front end housing.

Is your engine assembled with a gasket between the front cover and the end housing. If so this is where the problem lies. It seems that the newer gaskets are a little thicker than the original and holds the front cover too far away from the end housing. This prevents the o ring from being compressed enough and it blows out.

Check out Mazdatrix's web site. Their FAQ section explains this in detail

Bill4224

i did just replace my front cover, its a 90 motor with an 87 front cover, i did not use a gasket, and i used the rubber and teflon o rings. do you think thats still the problim??, i really don't want to have to take it all apart again :*(


thanks

copandengr

OH MY GOD!!!!!!! If you used the teflon o ring plus the rubber o ring then that is absolutely definately for sure the problem. The teflon o ring or washer is worse than the gasket at preventing the front cover from compressing the rubber o ring enough.

Replace the o ring but use it alone this time. You need to get a one inch long piece of 3/16 steel brake line and make a stand pipe to insert in the oil gallery that is on the driver's side of the front end housing. This will be a tight fit into the end housing but will slide very easily into the front cover (you may even have to file it a little to get it into the end housing). Its purpose is to prevent the silicone from plugging this oil passage up. This passage supplies the oil to the OMP.