sudden oil press. drop & rap

[outback maine]

98 outback 2.5 ran fine quiet smooth etc. sudden oil pressure drop and rapping started, took to "Subaru Specialist" said noise was timing belt tensioner and some from clutch area. I thought it was low oil press. and a spun brg.. $491.00 later same low oil press light flickering at idle and rapping in motor when you rev it a little but fairly quiet at an idle, but light on after warmed up. Am I nuts here or do I need a motor? Are these 2.5's known for this? Car has had oil and filter changed every 3000 mi. at least while I have owned it. Is this worth putting another engine in with 140000 on the replacement and 202000 on the car or not? I love the car but have sunk a lot of money in repairs up to this point and not much of a gambler. I use this for transportation and am trying to save this as cheaply as possible. Any thoughts or suggestions on this? Lots of new parts and everything works great accept for the engine now:horse: Thanks, OM

[Fairtax4me]

Without an actual pressure reading it's hard to say, but it sounds like you need an oil pump.

 

You did make sure the oil level is correct? (I know that's too simple but it has happened before)

 

Can you post a video or sound clip of the noise? It might help diagnosis to get an idea of what kind of "rapping" is going on.

 

Worse comes to worse you can drop in a low mileage 2.2 and never have to worry about it again.

[Log1call]

You need to have the oil pressure checked cold and hot, idling and reving to maximum oil pressure.

 

Given that the oil pressure dropped suddenly I would doubt the oil pump was the original problem. If it was the oil pump that caused the problem, but it is now noisy even with the oil light out, I'd doubt a new oil pump will cure the problem.

[idosubaru]

This would have been a good case of asking before hand.

 

The oil pump backing plate screws come loose, very common, I remove every one every time I do a timing belt. What I'm not sure of - is if they actually can cause noise or reduced oil pressure - but my guess is yes.

 

Personally I would reseal or replace the oil pump. Parts are like less than $15 for a seal, oring and anaerobic sealant.

 

That being said, it could be a rod bearing as these engines are known to loose those. But I'd hate to assume that on something simple like the oil pump too.

 

Might want to mention this to the mechanic and see if he'll cut you some slack.

[nipper]

Once the knocking starts, you can't really go back. It may be academic, but buy a cheap oil pressure gauge, something in the 0-60 range so we can read the bottom end pressure. You dont even have to mount it in the car for now. #4 cylinder bearing is the last to get oil pressure in the crank, so they are usually the first to give up the ghost. Blu threw a rod at 191,000 miles because the PO changed oil only once a year.

 

Closely examine the car. Check for rust. Are the seats and interior in good condition? How is the body? Skip wear items as well they wear.

 

If it all checks out, then yes a replacement engine is worth it. An option is a 2.2L if you can find one with lower mileage.

 

 

nipper