What Oil Pressure Do You Have?

[RBtwin]

Hi just wondering what oil prssure you have.

New motor RB30/25, RB25 oil pump, RB25 oil feed restrictors in the block. 110psi cold with 20W-50 garbage oil for run-in. Haven't got much oil temp in it yet to see if it goes down. Does anyone else get high pressure cold? Has anyone experienced by-pass valves sticking in the pump? The pump was pulled apart and looks to be in VGC before install.

Please help. Thanks.

[PlasticStan]

On my RB25DET I get between 7.5 Bar (108 Psi) to 8.0 Bar (116 Psi) on a cold start, drops to 2 bar at idle when it's up to working temperature. So 110 Psi (7.6 Bar) is good oil pressure for a cold start I'm using 10W40 Motul 300V Synthetic oil.

Edited November 19, 2005 by PlasticStan

[R31Nismoid]

Hopefully you arent taking it from the stock gauge...

they are known to be a little "inaccurate" at times

[T04GTR]

thats pretty normal oil presure.

my 170000km old rb26 has 7 bar at idle stone cold with penrite 5w60

at idle 2.5bar when hot.

when hot it maxes out at 7-7.5bar

[RBtwin]

You guys made my day!!! I was just about to pull the sump off and I really wasn't looking forward to it!

The gauge is TEMPORARY for tuning- autometer pro comp liquid filled mechanical gauge (not that it makes much difference) and i bled it properly.

I might try and get some thinner oil to start with now to drop it a bit. Thanks.

[Ezz35]

I was starting to wonder what pressure it should be running(RB25), higher when cold then commin down....good to know thats normal...i am how ever just reading it from the stock gauge

[The Dan]

110 psi is not normal

60-70 psi is normal on cold startup

15-20 psi once at operating temp at idle

25-35 psi between 2-4 grand

35-45 psi between 4-6 grand

50-60 psi over 6 grand

[T04GTR]

15-20 psi once at operating temp at idle

25-35 psi between 2-4 grand

35-45 psi between 4-6 grand

50-60 psi over 6 grand

<{POST_SNAPBACK}>

is that with sewing machine oil? or with really really big bearing clerances?

[The Dan]

2 thou bearing clearances and a 10w30 oil

If you have more oil pressure than above then there is something wrong....unless you have set it up for those pressures.

Plus if you read the manual it will tell you similar figures.

BTW...nice attempt at sarcasm but those figures are accurate. Even with an N1 oil pump you shouldn't expect any more than 80-90psi cold start.

[RBtwin]

I guess I'll have to take some relief valve pressure out of it because I don't have oil squirters so that would cause higher pressure.