Aerovee normal oil pressure

[billmaxmcw]

My oil temps take 20 minutes of flying to get up to 100 deg. measured at the oil cooler. So instead, I warm up on the ground until the CHTs are all over 200 deg. before takeoff. Oil pressures 80s on startup, 40s at cruise. VR-1 20w50 oil.

[Rynoth]

Thanks for all the responses, sounds like I'm in the ballpark, just need to get it flying to see the final numbers!

[jwd3ca]

This is a very interesting and topical thread as I get ready to start my engine for the second time (after dealing with a perceived 'tight' initial assembly, see previous posts). I have an old mechanical gauged temporarily attached via copper tubing to the port on the forward r.h. engine block, as well as my E.I.S. electrically connected to the oil pressure sender supplied by Sonex. With plugs removed, spinning over via starter only, I'm seeing the mechanical gauge gradually peg itself at over 100 psi. Whether it is accurate or not, I don't know, as it was just kicking around the shop, but the EIS seems to verify high pressure (gradual climb to ~99). I'm wondering if maybe I've messed something up as far as the two pressure relief valves are concerned?

[MichaelFarley56]

While I'm not a VW expert, if you're getting 100 psi by simply spinning the starter I'd say you have a stuck plunger causing issues. People have popped oil coolers with that same problem...if you're spinning your engine a few hundred RPMs and get that pressure, imagine what pressure you'll get when you idle your engine at 1000-1200 rpm!

If it were me I would pull the pressure regulator plunger (the one by the flywheel) and make sure it moves freely in the journal. It may be jammed.

Just my two cents of course!

[jwd3ca]

Yes, agree, seems overly high. But just to add another couple of data points:
- I'm currently currently using inexpensive multigrade (5W30) motor oil, planning on changing to break-in oil after maybe 15 minutes of low rpm running. Ambient temp in my shop ~10C (50F).
- I have no oil cooler installed, and am connecting the in and the out ports at the pump (as I understood the manual to suggest was an option).
- when I [briefly] had the engine running a couple weeks ago, the pressure stabilized at around 75-80.

Thanks.

[MichaelFarley56]

Again, this is just my opinion but I wouldn't use a non-recommended oil, even for short runs. The recommended oils all have high zinc content which is ideal for our solid tappet lifters. If you run your engine with "regular" oil you may set your lifters up for excessive wear, even for short engine runs. For the relatively small difference in cost I highly recommend using approved oils only.

[Corby202]

If you have put the engine together using assembly lube, the pressure will most certainly be high initially, untill the oil has replaced the assembly lube anyway.

[jwd3ca]

Good point. mate. I did use assembly lube on the lifters...

[jwd3ca]

Attempting to check my pressure relief(s), but can't extract the plunger/piston using a magnet. Any suggestions?

[marsolgp]

As long as the relief pistons are installed correctly, that is open end of the 'cup' facing down, just take a pair of needle nose pliers and insert into 'cup' and open pliers to grip inner wall of piston. That's worked for me in the past..... Good luck.