-stig-

Hello guys!

here is an update..

The engine is back in the car, and still not as it should be.

i changed the front cover, oil pan and pickup.

have visually inspected all oilgalleries under the frontcover, and around the filter, no signs of trouble.

the numbers is now 28psi idle (1100rpm) and never over 58psi while driving / WOT. it just stops there, and never goes over. pressure drops a bit when the engine rews over 5000rpm.

sooo, now its just the front plate and one rotor left of the orginal engine that had this problem the first time..

damn...

jantore

Im the guy that rebuilt the engine after it failed with a total front bearing seizure.

We noticed the oil drop on the dyno session where it made 400rwhp. So we aborted the dyno session and i drove it home. All was fine and the pressure at 3000 rpm was ok.

Now the owner got the engine back and i told him that he should contact the guy that built the engine the first time. And have him fix the oil problem. He said that oh it was a gauge problem and that he should just drive the car. Well the car failed after a little while and took alot with it. Only thing salvageble was the front plate, the front rotor and the rotor housings.

I changed as said inermediate plate, rear plate, rear rotor, stock e-shaft, all bearings, oil pump, rear oil pressure regulator(Mazda motorsport one). Engine was balanced and ported and so on. Should have been a great engine.

Now to the problem.

The engine got a pretty low idle as Stig writes. It hit's a max pressure as Stig writes as well. But once it goes beyond 4500-5000 rpm the oil pressure drops. At 7000 rpm it's down to about 35-40 psi wich is low.

My 13b-rew BP engine holds 120 psi flat from about 3000 rpm all the way to 9000 rpm. So something is up. Even my 4 rotor with big oil jets got more oil pressure

Anyone that could help Stig out would be great. Im located on the other side of the country so not so easy to get there and have a look as well.

Thanks

JT

Tem120

iTrader: (5)

Well .. I'm having similar issues I started the car today .. just at idle . as this is a rebuild from a shell , used motor , but the motor seems to be in pretty good shape.

new fuel pump ..


I started it 60 PSI .. it gradually went down as it heated up . and reached almost 0 .. i tried giving it a little gas when it was at 15 . to see if the gauge was working and it went up a little .. then down to almost 0 so I shut the car off .. I've been trying to figure out what it could be .

I'd be jumping for joy with 25 psi .

These points of measurement where are they exactly if you dont mind specifying for me? I'm getting a pressure gauge to measure it directly , But I'm not sure where the measure points are.

jantore

Do you use the stock oil pressure gauge?

If so you can't trust it. It sucks big time

Tem120

iTrader: (5)

I changed the oil filter , cleaned out the pressure sender , cleaned the connections and it is at a steady 30 now.

Rx_Sam

i don't want to open a new thread but i also have oil pressure problem. at cold start my oil pressure is 8 bar of pressure with an original oil pressure regulator.
with a modified (pressed) one i had 5 bar. could it be that the original pressure regulator is failing ?

Tem120

iTrader: (5)

my oil starts up at around 100 on cold starts but then quickly falls to 60 , then 30 .

how long does it stay at 8 bars?

jantore

depends on how "thick" the oil is. Some oils will give you quite high startup oil pressure. The thicker it is the more pressure. I have seen 10kg with stock oil pressure regulator

JT

Rx_Sam

i use 20w50 mineral oil

-stig-

just to continue the thread,

I had no time for further trying and failing with this engine, it costs to much money for the client, so i just build a new motor for the guy, and stuck it in his car.

now there where no problem with oil pressure, never ever under 40psi and a steady 110psi when you toutch the throttle. engine dynoed 425rwhp at 19psi.

the old engine stand on my bench, in pieces... the plan is to change the front plate due to the pressure problem, and the rear plate due to corrosion. then its showtime..

qle227

My pressure indicator is working fine when I start up the car cod the psi is 60psi and after driving it in a stop and go traffic, the oil pressure indicator show only 20 psi. any suggestion???

stuwk1

So I have nearly the same problems as you described. When you took the motor appart did you find an exact problem?

RotaryEvolution

iTrader: (30)

could be a mismachined front stat gear or loose tolerances between one of the stat gears and the irons.

FD:)

I have the same problem.
2 bar at idle. 3 max when I drive it. If you free rev it the pressure goes down.

Fresh engine. New rotor oil seals and rings.
New water and oil seals and orings throughout.
Penrite 15-40 mineral oil
Evans fluid
Had a spacer in the crank bypass valve but I have removed it and no change.
Car smokes a lot too.
The irons have been ground, renitrided and blocked back with oil stone.
I did flow the oil pump supply gallery but I didn't mess with the port where the pump picks up the oil.

Tried two senders and a mechanical gauge. Same reading.

I'm about to drop the sump and check the pickup and pressure relief valves.
If I dont find anything there i will take off the front cover and put a new pimp in.
And if that doesn't do it ill have to pull the motor out and strip it down.

jantore

I think the solution was to replace the front plate with a new one. Now the oil pressure is perfect on it.

JT