stuckagain Posted November 3, 2005 Share Posted November 3, 2005 Does anyone have any idea what would cause a rapid and immediate loss of oil pressure? There do not seem to be any leaks. Oil is fresh and clean (about 150 miles on it) though it does have a slight odor of gasoline to it. I am almost certain it is NOT the sending unit or gauge that is at fault. I took my 1990 Loyale 4WD SPFI out for a drive today. It's cold here now, last night the temperature was 10 deg. F. After warming up the engine I drove about 2 miles when I noticed that oil pressure gauge was reading ZERO. I listened for lifter noise and decided that it was louder than usual. I pulled over opened hood and based on the noise coming from the engine shut off engine immediately. I have not yet tested the sensor or gauge, but based on the engine noise I am certain that it is working. The car is parked about 2 miles from my home and I don't relish the thought of working on it outside at 20 F parked on a snow covered gravel parking lot so I'll probably have to tow it. Any suggestions will be greatly appreciated! Link to comment Share on other sites More sharing options...
Ross Posted November 3, 2005 Share Posted November 3, 2005 Perhaps the oil was too thick in the cold and the oil pump broke? Link to comment Share on other sites More sharing options...
stuckagain Posted November 3, 2005 Author Share Posted November 3, 2005 Perhaps the oil was too thick in the cold and the oil pump broke? Ross, thanks! That was my first thought - but timing belt didn't break and there didn't seem to be any odd noises coming from the pump and no leaks around it. Is it possible for the pump to fail that quickly? The car has 115,000 miles on it and I think the pump is original equip so it's due for a change. Link to comment Share on other sites More sharing options...
Ross Posted November 3, 2005 Share Posted November 3, 2005 Ross, thanks! That was my first thought - but timing belt didn't break and there didn't seem to be any odd noises coming from the pump and no leaks around it. Is it possible for the pump to fail that quickly? The car has 115,000 miles on it and I think the pump is original equip so it's due for a change. It is possible that it broke internally (what type of oil are you using?) but i've never actually heard of it happening. Before you go changing it, make absolutely sure its not the gauge, cos its gonna annoy you if you change the pump then realise its no better. Could also be the relief valve, another thing to check before doing the pump - not sure where it is on an ea82 someone else will have to tell you that. Link to comment Share on other sites More sharing options...
stuckagain Posted November 3, 2005 Author Share Posted November 3, 2005 It is possible that it broke internally (what type of oil are you using?) but i've never actually heard of it happening. UGH! 10W-30, but it's not that cold here. Before you go changing it, make absolutely sure its not the gauge, cos its gonna annoy you if you change the pump then realise its no better. Yup, will be the first thing I test with meter tomorrow. Could also be the relief valve, another thing to check before doing the pump - not sure where it is on an ea82 someone else will have to tell you that. I have manual - shows relief valve to be opposite oil filter on oil pump assembly. Should be able to get at it. I'll check it before I pull the pump. Thanks again! Link to comment Share on other sites More sharing options...
Ross Posted November 3, 2005 Share Posted November 3, 2005 UGH! 10W-30, but it's not that cold here. Yeah, after converting it to degC (so i know what your talking about!) its not that cold - i'd have thought 10w would be ok. Link to comment Share on other sites More sharing options...
Syonyk Posted November 3, 2005 Share Posted November 3, 2005 It's cold here now, last night the temperature was 10 deg. F. Seriously? Alaska, 10F, cold? I always figured you guys waited until 0F or so to stop wearing shorts. You didn't explicitly mention it - have you confirmed that the oil level is normal? -=Russ=- Link to comment Share on other sites More sharing options...
stuckagain Posted November 3, 2005 Author Share Posted November 3, 2005 Seriously? Alaska, 10F, cold? I always figured you guys waited until 0F or so to stop wearing shorts. You didn't explicitly mention it - have you confirmed that the oil level is normal? -=Russ=- Well like I said, I don't think it will be fun working on the car on a snow covered parking lot, in my shorts. Oil level is good - oil is clean and clear. Just did an oil change about 150 miles back. Link to comment Share on other sites More sharing options...
stuckagain Posted November 4, 2005 Author Share Posted November 4, 2005 Problem solved - solution cloudy. I'm happy I stopped driving the car when I did. I was correct - there was NO oil pressure. It was a balmy 18 F. in the parking lot so working in my shorts didn't present any problems (unlike those days when the tools stick to your skin because it's sooo cold). Here's what I did. 1) Double checked oil level - OK. Checked for obvious leaks - found none. 2) Checked dash gauge. Grounded the wire that connects to the oil pressure sensor and turned on ignition. Gauge took off and slowly moved up the scale. Gauge - OK. 3) Removed oil pressure sensor from the oil pump and installed an oil pressure gauge (Matco) to check the pressure. Started engine. Oil pressure moved up to 14 psi (very low) at cold idle and after about 45 seconds dropped to zero. Turned off engine - pronto. 4) Removed end plug from "oil pressure relief valve" and extracted spring and plunger (also spent time trying to find the small spacer that fits between spring and plug after it fell on the ground). Put the valve back together and reinstalled oil pressure sensor. 5) Started engine. Oil pressure gauge rose ever so slightly so I did not shut off the engine but rather, on a hunch revved it to about 3000 rpm several times. Something opened or dislodged itself because the oil pressure started coming up after about 45 seconds. The sound of the engine changed the instant the pressure gauge started to rise; the engine becoming much, much more quite. I can only speculate that perhaps the relief valve had become stuck in a return flow position or, more likely I think, something was blocking the flow of oil into the pump. Perhaps both. Dunno Thanks to all for the suggestions. Link to comment Share on other sites More sharing options...
stuckagain Posted November 4, 2005 Author Share Posted November 4, 2005 I can only speculate that perhaps the relief valve had become stuck in a return flow position or, more likely I think, something was blocking the flow of oil into the pump. Perhaps both. Dunno Sorry to be so chatty, but if this helps someone then it's worth it. Is it possible that the oil pump became "vapor locked," perhaps trying to pull up thick oil? I seem to recall that one of the manuals I read suggested packing the oil pump with vasoline before installing it so that it would create a vacuum when first used. When I removed both the "oil pressure sensor" and the "pressure relief valve" oil flowed from the sump and out of the open holes. Perhaps enough oil flowed into the line to create enough of a vacuum for the pump to begin working again???? Just a thought. Link to comment Share on other sites More sharing options...
nipper Posted November 4, 2005 Share Posted November 4, 2005 i agree. Usually i filll the oil pmp with olt (or try to) before i clse it up fure things up. Thst the one down side to subaru engines, its hard to prime the oil system before starting to avoid all this nastyness. nipper Link to comment Share on other sites More sharing options...
stuckagain Posted December 23, 2005 Author Share Posted December 23, 2005 UPDATE - no oil pressure mystery solved. I've been down in the lower 48 for the last 4 weeks but am home now. Today I decided to put in a new oil pump. When I pulled off the timing belt covers the toothed pulley for oil pump fell to the floor. I'll file this one in the "lessons learned" folder. No mention in the Subaru EA82 manual of loose or detached pulley on oil pump in the Engine Lubrication trouble shooting section under "no oil pressure." I have no idea how the pulley managed to come loose from the pump, but it did - hence, no oil pressure. I've decided to leave the timing belt covers off for a while; never liked 'em much anyway. Link to comment Share on other sites More sharing options...
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