jmporsche944

Alright, so.. a while back I changed my timing belt, and was having oil pressure problems... turned out I had bent the P/S pulley when torquing the crankshaft bolt down. I got one off a parts car from Andy, and put it on.. and im still having problems. Im 99 percent sure I didnt bend this one too.. when the engine is on, and I look down at the P/S and timing belt pulleys on the crank, they look to be spinning correctly (not wobbeling like when the bent P/S pulley was on).

The oil pressure rises with RPM like it should, but its just too low. At idle, it is at 1 bar, and will rise to about 2.5 maybe 3 when driving. The light usually flicks on for a second when I go to stop.. becuase the car drops below its normal idle speed for a split second until it returns to its normal idle. So.. what do I check next?
TIA

mark944turbo

Try replacing or rebuilding the oil pressure relief valve and while you are at it replace the oil cooler housing seals. These 2 things fail and cause oil pressure problems.

You did torque the crank bolt to spec I am assuming, if not, do that first.

What weight oil are you using?

jmporsche944

Yes I torqued the bolt down to 155 ft/lb. Im using 10w40 oil. Should I be using a thicker oil?

Say the problem did lie in the pulleys on the crank.. is the only reason for loss of oil pressure becuase the bolt slowly backs out and does not provide enough friction to run the oil pump?

mark944turbo

Your oil is fine. Unless you are low on it..

The only thing with the pulleys is the torque of the bolt. There has to be enough friction to drive the pump. Maybe take the bolt out, clean the hole, and put it back?

Otherwise I think it has to do with your oprv and you have a coincidence w the timing belt job.

michaelathome

Here is what I have on my oil gauge. Granted I didn't have a thermostat at the time but... This is an early N/A as well.

- While cold or at lowest temp averaged between 4.5 to 5 bar oil pressure on the gauge at idle.
- While at highest temp dropped to 1.4 bar oil pressure on the gauge at idle.
- While at temp at idle 1.4 to 5 bar oil pressure on the gauge depending on if fan was running ot not.
- While at temp with throttle 3.5 to 5 bar oil pressure on the gauge. Fans running when they needed to.

- Both fans kick in at 1.4 bar on the oil pressure gauge at idle.
- One fan (driver side) runs as long as I have the AC fan on, PERIOD!
- Both fans kick in when car is stationary and has reached maximum temp.

I am currently using Castrol GTX 10/40 and a 70-30 coolant/water mix in my system.

Obviously things will change with different oil weights/types and coolant combinations but I figured that I should post it for those that are looking for info at some later time.

I will try to get the same or similar readings now since I have my t-stat hooked up and working.


Hope that helps,

Michael

jmporsche944

Thanks for the info Michael...

My oil pressure is normal at startup (runs about 4 to 5 bar) but after driving for about 10 minutes.. i start having problem... what are the symptoms for a bad OPRV?

jmporsche944

I do find it unlikely to be anything except the pulleys on the crank though.. it would be to odd to be a coincidence with the timing belt change. Is it possible to not have the pulley behind the P/S pulley on correct? If I remember correctly it was keyed, so I cant imagine that I put it on wrong? I just want to get as much info as possible before I put the flywheel lock back in and take the timing belt off to find out that I wasted my time. Thanks.

michaelathome

Pull the power steering belt and give it a try again, is the PS belt needed? You could pull your alt belt too and see if the readings are the same.

My guess it that you jostled a wire or the PS belt is not functioning correctly.

Pull the belt and give it a go. Your car will not have PS but I would bet with the wheels off the ground right now that it really matters.

Michael

jmporsche944

Well, since its only after the car has warmed up.. I could probably pull the P/S belt and try that.. Just curious though as what your thinking is on this?? Theres no problem driving the car without the belt on right?