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I was wondering why my oil pressure is so low lately. When i bought the 87 gl wagon the pressure would start out at about 75 while it warms up and a little lower than 45 when warm. but now it warms up at 35 and idles at 10 i dont know if this is signs she is about to kick or if i need a new oil pump or what cause im about to go on a road trip and i dont want to get stuck somewhere

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sounds normal.

could be due to warmer temperatures/summer. your owners manual will explain that this is normal, it specifically mentions oil pressure.

 

it could be reading low just due to the sending unit being old/dirty/bad connection. it's the one wire sensor in front of the oil filter if you want to have a look at it. just pulls apart and slides back on. that connections could be bad or the sending unit is old. if it was anything mechanical i'd guess the sending unit first. they are cheap and super easy to replace.

 

you could be loosing some pressure due to age, but that would only be gasket related, not oil pump related. unless something really odd was going on, you will be fine to take your trip.

 

if there are other symptoms, lots of oil loss/leakage, or something like that then let us know and we'll go from there. otherwise you're golden.

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I have the same issue ... "normal" for me (or so i thought!) was somewhere between 10 and 15 lbs ... that's where my needle always seems to be ... but ironically enough, the pressure seems to DROP when I up the RPMS ... I kinda thought this was normal, since I don't seem to be feeling any side-effects and it's my 1st Soob. 1990 Loyale Wagon 1.8

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I was wondering why my oil pressure is so low lately. When i bought the 87 gl wagon the pressure would start out at about 75 while it warms up and a little lower than 45 when warm. but now it warms up at 35 and idles at 10 i dont know if this is signs she is about to kick or if i need a new oil pump or what cause im about to go on a road trip and i dont want to get stuck somewhere

 

That sounds a bit low to me.. I just installed a new oil pump on my EA82T and cold I'm seeing around 65-70 psi and warm prolly around 45 psi ( I'm guessing - I haven't run the engine long enough to really warm it up ). Note that these measurements were with an oil pressure guage attached to the pump, not through a dash instrument, so they should be very accurate.

 

If you're up to it, I'd suggest pulling that oil pump off and checking all of the tolerances very carefully, and of course replace your seals. Then check it with an oil pressure guage screwed into the pump and see what you get. Honestly, if you take it off, you should just replace it. I got a new one for about $60 from a local parts store, which is definitely worth the insurance. You don't want to run on low oil pressure for long b/c oil won't be able to get to all the places it needs to go.

 

Cheers

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I've adopted the general rule of replacing oil pumps every 100,000 miles. After throwing a rod through the block on an EA81 due to bad oil pressure, I don't mess around anymore. Do as you like, but I would replace the pump, and I'm on at least my 10th subaru.

 

anything less than 15 psi at warm idle (and I like to see more like 20 - 25) and the pump needs to go. I don't reseal pumps - on the EA81 it's just an excersize in futility, and on the EA82 it takes so damn long to get the pump off and replace it that the extra $60 for a new pump rather than just a seal kit is well worth it in my opinion.

 

15 - 25 psi warm idle, and 40+ at 2500 RPM warm. Any less and something is amiss. Period.

 

GD

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Okay, I took some snapshots of the pressure @ vraious RPMs ... and it kinda goes against what I said earlier. Even tho I swear the pressure is better sometimes at idle

 

Here's close to Idle ...

 

DSC00002.jpg

 

Here's 2000 rpm

 

DSC00006.jpg

 

and at 3500 rpm (yes, these are all under-load, except the idle)

 

DSC00008.jpg

 

Now that I read the responses here, I'm thinkin' this ins't good...

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before you shoot the pump..replace the sending unit...real easy to get too and just turns right off with a wrench or pliers even if your desperate...doesn't cost too much. Had the same problem with my loyale, everything seemed to be running fine but the pressure just started reading low, then eventually it started dropping to 0 at idle, I just replaced the little sensor/sending unit and it jumped back up to normal on the gauge. my $.02

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It's my studied opinion that if EA-82 owners want meaningful oil pressure readings, the gauge in the dash must be ignored, and a mechanical guage must be installed somewhere, somehow.

 

The guage in the dash is notoriously innaccurate, for a variety of reasons. I came to that conclusion only after reading several years worth of "oil pressure threads" here at USMB.

 

It's not that hard to install a quality mechanical guage, and well worth it, if you love your Soob that is. And oil to an engine is like blood to us.

 

Definately, mechanical over electric, though a new aftermarket electric is far better, I suppose than what these cars come with.

 

Luck,

Pyro

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before you shoot the pump..replace the sending unit...real easy to get too and just turns right off with a wrench or pliers even if your desperate...doesn't cost too much. Had the same problem with my loyale, everything seemed to be running fine but the pressure just started reading low, then eventually it started dropping to 0 at idle, I just replaced the little sensor/sending unit and it jumped back up to normal on the gauge. my $.02

 

Thanks, man! yeah, I just priced oil pumps after posting this to check things - $245 a the Stealer, and $143 here at the local JapImp place. Sending unit is like $25 bucks, if I remember.

 

The guage in the dash is notoriously innaccurate, for a variety of reasons. I came to that conclusion only after reading several years worth of "oil pressure threads" here at USMB.

 

But given this ... hmm. Still, I suppose if I do the sending unit and the gague DOES change, then I do have relative better pressure, even if the gague is way off ...

 

Thanks Guys!!!

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Thanks, man! yeah, I just priced oil pumps after posting this to check things - $245 a the Stealer, and $143 here at the local JapImp place. Sending unit is like $25 bucks, if I remember.

Look around more. I had to check about 6 places before finding mine so cheap. The prices on those pumps are all over the place for some reason. Dig, and ye shall find.

 

But given this ... hmm. Still, I suppose if I do the sending unit and the gague DOES change, then I do have relative better pressure, even if the gague is way off ...

Get an oil pressure tester and screw in to the pump - that's the only way to know for sure.

 

Cheers

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I'm gonna show up and agree on two counts... first, my XT6 reads about the same as yours...the dash gauge. Its just the sending unit being old. Second, that gauge smells... it barely moves... I got these

100_0298.jpg

at walmart, for like $25, but you can go to autozone and get full size gauges for about $30.. complete, no reason not to... My oil pressure gauge moves with the engine RPMs... not all slowly like the dash gauge... Actually I still have the stock one hooked up, and its not anywhere near right... if you are concerned about oil pressures... get a good gauge first...

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I'm gonna show up and agree on two counts... first, my XT6 reads about the same as yours...the dash gauge. Its just the sending unit being old. Second, that gauge smells... it barely moves... My oil pressure gauge moves with the engine RPMs... not all slowly like the dash gauge... Actually I still have the stock one hooked up, and its not anywhere near right... if you are concerned about oil pressures... get a good gauge first...

 

How do you hook up a mechanical gauge on an EA81 or EA82 Sube? How do you keep it from leaking at either end of the tube? Any special adaptors needed that don't come standard with the gauge kit?

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This was my solution - I added a right angle fitting to it later as the plastic line likes to kink otherwise, but that's just a 1/8" NPT fitting from Home Cheapo.

 

http://www.ultimatesubaru.org/forum/showthread.php?t=55186

 

I also did my lifted wagon, and it's done with braided SS line to the sending unit as it's an off-road toy - same principle tho - metric adaptor to 1/8" NPT to whatever you like - mechanical like my EA82 sedan, or relocated sender (Autometer in the case of my wagon):

 

sender3.jpg

 

GD

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This was my solution - I added a right angle fitting to it later as the plastic line likes to kink otherwise, but that's just a 1/8" NPT fitting from Home Cheapo.

 

http://www.ultimatesubaru.org/forum/showthread.php?t=55186

 

I also did my lifted wagon, and it's done with braided SS line to the sending unit as it's an off-road toy - same principle tho - metric adaptor to 1/8" NPT to whatever you like - mechanical like my EA82 sedan, or relocated sender (Autometer in the case of my wagon):

 

GD

 

That's a thing of beauty GD.. :clap:

 

N

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