No oil pressure!

Busdriver · Post by **Busdriver** » Sat Nov 27, 2010 1:36 pm

My old man rang me the other day and had a problem. He had changed the oil in his stock L series and the oil light wont go out. Thats all he did, just change the oil. Got to have a look this morning and pulled the oil pressure sensor switch out to see if it had any oil pressure or not, and it didnt. Pulled out the oil pressure relief valve and replaced it with another, no change so pulled off the oil filter and checked that the bypass valve hadnt fallen out. Nope, it was ok too. Oil filter still had oil in it but the gallery that feeds it was bone dry. Got another filter and filled it with oil and put it on and started the car and Bingo! The light went out and everything stopped rattling. I guess that he had an airlock in the oil filter and it wouldnt self prime, any body heard of such a thing before or got a different explanation? he was very happy to have it fixed relatively easy as he didnt want to pull it out to start stripping it down.Swears that he wont change the oil again either! Oh, he had it on ramps to do it, but I'm not sure that would make any difference, would it?

YouTube · Post by **El_Freddo** » Sat Nov 27, 2010 1:55 pm

I reckon this happened because he didn't swap out the oil filter for a new one - ALWAYS put on a new oil filter when changing the oil - the filter is the cheap part, the oil not so cheap so you'll want a clean filter to look after the oil and your engine.

What could have happened is that the air lock was created when the oil was drained resulting in a drained pick up line. When it was refilled the pick up line was then locked in with air. The old filter, still containing old oil and gunk may have had enough pull on it to over power the oil pump that was dry.

That's a theory anyway. Glad you got it sorted!

Cheers

Bennie

Busdriver · Post by **Busdriver** » Sat Nov 27, 2010 2:41 pm

Thanks El Freddo, I think thats what happened as well, have you heard of it before though? Hes 83 and a bit old school, so oil changes happen every 4000 km and a filter every second oil change, and I dont think I can change him now. At least he uses genuine filters.We are glad it was easily sorted too.

fullmetal · Post by **fullmetal** » Wed Feb 23, 2011 12:19 pm

Hi aside from changing subaru oil filter every oil change when do you guys change oil on your subaru? i change mine every 5000kms is that really advisable? i am really planning to reach 7000kms before changing oil because honestly El Freddo is right oil is not cheap. Good thing i learned it from here i didnt not change oil filter on my first oil change. lol.

YouTube · Post by **El_Freddo** » Wed Feb 23, 2011 1:47 pm

fullmetal wrote:Hi aside from changing subaru oil filter every oil change when do you guys change oil on your subaru? i change mine every 5000kms is that really advisable? i am really planning to reach 7000kms before changing oil because honestly El Freddo is right oil is not cheap. Good thing i learned it from here i didnt not change oil filter on my first oil change. lol.

I try to do mine every 10,000km - I personally don't see the point in 5000km oil changes, others will argue its the way to go. Each to their own!

I just know that with every oil change put a new filter on as well!

Cheers

Bennie

FujiFan · Post by **FujiFan** » Wed Feb 23, 2011 7:33 pm

I've found from experience with subarus and others, that you should always "prime" a new oil filter by pouring in about 100-200 ml (depending on physical size) of new oil and letting it soak for a few minutes before installing. Ever since I started doing this about 12 years ago, I have not once ever had the "Oil" light remain on for more than normal just after an oil and filter change.
My two cents...

discopotato03 · Post by **discopotato03** » Wed Feb 23, 2011 10:42 pm

Well the truth of the matter is that the only way you clean the lubricating system is to remove the used oil and filter .
Now I can't quote for EA81/EA82 engines but most if not all engines have a bypass valve either inside the filter or covered by the filter in the engines filter mount . Its there to prevent oil starvation if the filter blocks for any reason . A classic one is water through an oil filter because wet elements don't like passing oil afterwards .
There's no way to tell if the bypass valve has been opening and allowing unfiltered oil to pump around your engine .
Actually I've just been going through oil filters for the Evo 6 and it seems that Mitsy has the bypass in the filter and its set to open at 11-13 psi resistance to flow through the filter material . The equivalent Rycos are set do do this at ~ 15 psi .

Now old high mileage engines suffer more piston ring blow by and no doubt the front and rear Subie crank oil seals won't be flash if they've been there for lots of thousands of km . Generally its combustion products that contaminate lubricating oil so to removing them means new oil and oil filter .
Of my three cars engines the EA82T is the freshest but its also the least modern one .
I'll still change the oil and filter at 5000 though it has reached 7 at worst .
I use exotic and expensive oil compared to most and I think an oil service on Ellie owes me the best part of $80 with a Ryco filter .

Your calls , cheers A .