OIL pressure

[Jessie]

OK I have some questions about my 1986 Subaru XT Oil Pressure. It is a 4 cylinder engine. The engine is new, and was just put in the car. i have no experience with these at all to compare by. The cars runs and drives like a dream. However when I am at idle like a red light I noticed the oil pressure is just above 0. When I am driving it's just below 45. Is this normal? I am expecting while at a red light to find the engine ruined. When I saw this I took it back to my mechanix place right away and droped it off today. He is not open so I can't ask him. I hope this is normal, but I felt better to drop the car off and ask, than keep going and ruin a brand new engine. Thanks in advance for your answers and patients with all my questions.

 

Always,

 

Jessie Odell

Palm Beach FLorida

[hatchsub]

If your engine really had 0 oil pressure at idle you would have a ruined engine. IF i had to guess there is something wrong with your gauge. Ask the mechanic to put a manual gauge on the engine as this will be far more accurate.

[NorthWet]

Whether or not it is "normal", it is very common. The indicated pressure will sag to next to zero at idle when hot. 45 psi hot while at medium rpm sounds pretty good.

 

Your engine has hydraulic lash adjusters (like hydraulic lifters on an american pushrod engine) and they tend to be very sensitive to oil issues. If they do not get enough oil or if there is air mixed in with the oil then they will tap (aka tick of doom or TOD), sometimes very loudly. I test drove an Xt that had been sitting for a few weeks and it at first sounded like a rod bearing had let loose.

 

Anyway, if you had seriously low oil pressure the HLAs would probably let you know (sounding very much like rod bearings).

 

One of the common issues with the oil pump in your XT is that it has a special o-ring (mickey-mouse gasket) that tends to need replacement once in a while. It can leak pressure or allow air to get sucked into the pump.

 

Welcome, and enjoy your XT!

[Jessie]

Thanks so much for being so imformative for me. Now that you have pointed out the oil Pump issue I will forever be worried about.lol let me ask you this. I have had my mechanic Replace everything under the hood. The new Engine came from a company in Ca called Makato. There was nothing on the engine, not even the oil pick up tube. the only thing I think that was there was the oil pump. I am not a mechanic, so forgive me for sounding stupid.lol If they redid that engine and it came with the oil pump in it, would they have most likley have replaced that ring already? If not would my mechanic have had to while assembling the engine. You said that ring needs to be replaced sometimes. How often do you recomend, are we talking 5,000, miles, 50,000 miles? How can I check it? It is hard to change? sorry to bombard you with questions. I just know nothing about this car other than I love it. If it where a mercedes I would have the answers.lol I am a service fanatic. I change the oil in my cars ever month, weather they need it or not. I lost a antique Mercedes Diesil due to loss of oil pressure, so the whole oil pressure thing has be very concerned. I just want to make sure I maintain it right and avoid anything that would cause me to loose the car. The mercedes lost pressure because the place that changed the oil did not install the oring in the oil canister correctly, and when I noticed the pressure was gone, it was to late. RIP 300 D.lol thanks again for all your help guys.

 

 

Jessie Odell

Palm beach Florida

[NorthWet]

"Don't Panic!" - Douglas Adams

 

By "no pickup tube" do you mean that there was also no oil pan on the engine? (the pcikup tube is inside of and hidden by the pan.

 

If the engine has been rebuilt, the gasket should have been replaced. Don't fret over it, as it is nothing special or prone to failure. It is just a known cause of low oil pressure or aerated oil in the EA82 engines. It is normally replaced by "people who know" whenever they change their timing belts, as the t-belts have to be removed to get at the oil pump.

 

Unless you have a real reason to be concerned that your pressure is too low, I wouldn't worry. I have a turbo-wagon that registers negative pressure at idle (sender is a little screwed-up). It is difficult to tell exactly how accurate your particular sendor/gauge combo are, but your engine will tell you if the pressure is too low.

[Jessie]

Yes the oil pan was on the car. Here is the story about the engine's.lol I bought the frist new engine for 700.00 plus shipping. The engine came, they took the bad one out of the car, it sprouted legs and walked off. None the less they installed the new engine and discovered it would not build oil pressure. The mechanic told me he had been over everything and hated to inform me but my new engine was bad. So I called the company, at my shipping expense they sent out another engine, just like the other new one. The mechanic put it in the car, same thing no oil pressure. He tells me again bad engine. By this time I was loosing my patients and told him, there has to be a reason, if you know what your doing you should be able to find a way to fix it, there is no way I could have gotten two bad engines. The place I bought the engines from is a large and reputable company. I called in someone else, who works on my Mercedes cars. He went and had a look, frist thing he did was take the oil pan off and discoved there was no oil pick up tube. So we got the tube from a Subaru Dealer put it in and wala the engine was fine. Then he checked my other new engine and it was the same thing it with. So now all seems to be well. And I do have another new spare engine if anyone is in the market for it. AS I have been told Subaru's go forever, so hopefully in my life time I should never need another engine for it. What brought all this on, was when I purchased the car, the engine in it was knocking badly. The mechanic told me someone had ran it hot and blew a head gasket and in order to replace the head gasket the engine would have to be pulled, and it was going to cost me some bucks. So I came up with the idea if it's gonna cost me and were pulling the engine anyway, replace it and everything else under the hood so I will get years of trouble free driving, hopefully. That is what started the complete restoration. So almost 5,000.00 later, I feel pretty safe in thinking it will take me anywhere for a long time to come. LIke I said before, I have never owned one, so just like any other car there are things that are prone to happen to them if you don't know what to watch out for. Thus the reason for all my questions.lol Thanks again for all your input.

[4x4moose]

i'm kind of interested in the motor, even tho this is the wrong place to talk about buying something. is it carb or spfi

[NorthWet]

i'm kind of interested in the motor, even tho this is the wrong place to talk about buying something. is it carb or spfi

XT is almost certainly MPFI. Doesn't sound economical to me, even if it fit. Totally opposite corner of the continental USA, rebuilt by a company that doesn't think to put in the oil pickup tube (which, IIRC, are supposed to be the devil to remove in the first place), CCR being closer, and JDM importers being closer still.

 

Jessie, that sounds like some story of adventure. Glad it wasn't one that I had to take. The headgaskets wouldn't have been too big of a deal, but I can understand that if you are having a shop do it that a new rebuilt would look attractive. That "knocking noise" could very well have been the previously mentioned HLAs ticking.

 

Good luck, and watch out for sharks... We tend to be a ... ummmm... "frugal" group of car cultists, thinking in terms of a couple hundred bucks for acquiring a car and getting it running. Some sleeze who hears how much you have put into your car so far might try to overcharge you for stuff, or just charge and disappear.