Fuel In Oil

Reply Subscribe

Thread Tools

Search this Thread

10-16-2003, 01:00 PM

#11

TYSON

Senior Member

Join Date: Jan 2003

Location: London, Ontario

Posts: 2,871

I think the PFC does it by default. I always got 0ms under heavy decelleration.

This is likely why it would buck slightly coming down a hill with cruise control on, based on your descriptions.

10-16-2003, 07:14 PM

#12

setzep

Senior Member

Thread Starter

Join Date: Dec 2002

Location: Minnesota

Posts: 911

Wait a minute... just thought of something.. on heavy decel (27-23inhg) woulden't it want to pull oil in the combustion chamber instead of putting fuel into the oil??

10-16-2003, 08:42 PM

#13

BDC

Senior Member

Join Date: Jun 2003

Location: Grand Prairie, TX

Posts: 917

Quote:

Originally Posted by setzep' date='Oct 16 2003, 04:14 PM

Wait a minute... just thought of something.. on heavy decel (27-23inhg) woulden't it want to pull oil in the combustion chamber instead of putting fuel into the oil??

You'd think so at first blush, but it depends on the two competing forces -> pressure in the oil system through the crankshaft vs. combustion chamber pressure.

B

10-16-2003, 10:05 PM

#14

setzep

Senior Member

Thread Starter

Join Date: Dec 2002

Location: Minnesota

Posts: 911

Well in this case both forces would be working together to reach the same goal, pull/push oil into the combustion chamber.

10-16-2003, 10:54 PM

#15

j9fd3s

Senior Member

Join Date: May 2002

Location: California

Posts: 22,465

Quote:

Originally Posted by setzep' date='Oct 16 2003, 07:05 PM

Well in this case both forces would be working together to reach the same goal, pull/push oil into the combustion chamber.

i think it can wash down the housing walls like a piston engine, i have nothing to base this on but hey it sounds neat huh?

mike

10-17-2003, 03:42 AM

#16

IGY

Senior Member

Join Date: Dec 2001

Location: Okinawa Japan at McDonalds

Posts: 472

Yes the power fc does this automatically, but mine was fucked up. Yes you can minimize the problem by creating a lean condition in the decel vaccuum areas. Yes, it takes a long time to get the accel enrichments correct, to recover from zero fuel on decel, and yes fuel does have to be added from 1500-2000rpm's to eliminate idle surge, but it can be done. The power fc does this as a default, but everything changes drastically with different inj sizes and fuel pressures.

10-19-2003, 12:52 AM

#17

setzep

Senior Member

Thread Starter

Join Date: Dec 2002

Location: Minnesota

Posts: 911

Quote:

Originally Posted by IGY' date='Oct 16 2003, 01:06 AM

Check to make sure your ECU is cutting fuel on decel! I fucked up one motor (spun bearings) and thought I was just running to rich. I dialed in the fuel and was still getting fuel in my oil. One day I was watching my inj duty on decel and it was staying the same after I got off the gas. I also was making nice flame shows on decel. After I fixed the problem(inj duty goes to 0% on decel) I no longer get fuel in my oil(not anymore than the normal rotary).

How many miles were on your fuel enriched oil when the bearings let go? I think I've changed my oil 4-5 times in the 2600 miles I've put on my setup.

10-19-2003, 05:19 PM

#18

j9fd3s

Senior Member

Join Date: May 2002

Location: California

Posts: 22,465

ok i actually went at looked at mine (20b) and theres 2 parts to it.

the fuel vapor line comes from the tank to the charcoal cannister, and then goes to the vacuum rack (cosmo is multi peice, so i'm only using the pcv and metal fuel lines) where it goes to the oil filler neck. teed into that pipe is a hose that goes to the tid, with a check valve. the vapor/fuel/oil can only go into the tid. this is have hooked up like it came, ie its stock like this.

the second part, the nipple on the center housing right below the loi filler neck goes to a pipe which went to the purge valve (the round one) and then into the bottom of the tbody. this part i had blocked off, i just went and unplugged it so now it sees atmosphere, should it see vacuum?

mike