brentlysubaru Posted November 10, 2015 Share Posted November 10, 2015 I bought a 98 legacy outback with the 2.5 dohc for parts for my 93 impreza. The guy I got it off of just replaced both head gaskets timing belt idlers water pump balancer and oil pump right before he discovered that the right rear strut housing was gone. The engine is fairly quiet at with just a little tick at idle nothing to worry about typical noises but around 2000 or so rpm it almost sounds like a rod knock. You can't hear it sitting in the car but under the hood you can. Is this a normal noise for the 2.5? I was just wondering before I try and swap it into the impreza. Thanks in advance. Quote Link to comment Share on other sites More sharing options...
1 Lucky Texan Posted November 10, 2015 Share Posted November 10, 2015 confirm it isn't the timing belt flopping around due to a failed TB tensioner - can sound like rod knock, also, 'might' leave a 'rubbed' spot on the inside of the TB cover. 1 Quote Link to comment Share on other sites More sharing options...
mikaleda Posted November 10, 2015 Share Posted November 10, 2015 Ya I would suspect TB tensioner first, but its possible its just the lifters needing to be adjusted as well. I know some of these cars are just like that as well. How long have you owned the car with that engine? Ever been overheated badly or run low on oil? If not its probably safe to assume your motor is solid. Quote Link to comment Share on other sites More sharing options...
mikaleda Posted November 10, 2015 Share Posted November 10, 2015 Another good question to ask is did he use OEM headgaskets. If not I don't know if I would trust the motor to not blow the head gaskets again in another 10k miles 1 Quote Link to comment Share on other sites More sharing options...
Bushwick Posted November 10, 2015 Share Posted November 10, 2015 You can remove the timing belt covers and either verify or rule out the tensioner. When bad, it moves around abruptly. Any idea what weight oil he put in? I've seen a couple threads now where guys decide to ignore the factory recommendations and run a 5w 40 or 10w 40 and post they have a similar noise. With a 5w 40, it'll act like a 5 oil when cold (easier winter starting/cranking vs. 10w- "w" stands for winter BTW), then thicken to a 40 when hot. If it's quiet at start up and gets louder as it warms up, that could suggest the engine is having an issue with the 40 weight for example. I know when I replaced my lifters awhile back, there was a small amount of oil varnish built up in the rocker's oil feeds, which are rather small holes, and had varnish in the oil pump assembly's feed areas as well. It could be possible that an engine with a higher amount of varnish built up (like say the engine only had conventional oil it's entire life and was neglected at times), that there might be more of a restriction and the a 40 oil is too thick to clear it. Or maybe the oil pump is creating too much pressure with it? Maybe someone can clarify if I'm too far off base here? Another issue could be the guy mixed different oil weights which can bad. Either way, there does seem to be a correlation between running thicker oil and extra noises that appear to be coming from the tensioner. And given the tensioner is hydraulic, it might be an issue. Quote Link to comment Share on other sites More sharing options...
brentlysubaru Posted November 10, 2015 Author Share Posted November 10, 2015 I'll check the tensioner,I think he said that a new one was put on I'm not sure tho. After thinking about it the noise did seem like it was coming from the front of the engine. I was going to change the oil and filter because on the 2.2 in the impreza was noisy when I ran 10w 40 but when I put 5w 30 and it quieted down I'm not sure what brand of headgaskets were used he did say that they were a four layer gasket. Hopefully get to check it out tomorrow. Quote Link to comment Share on other sites More sharing options...
brentlysubaru Posted December 15, 2015 Author Share Posted December 15, 2015 Finally got to check and see if the tensioner was making the noise. When I took off the drivers side timing cover I noticed that the ac idler pulley was rubbing on the cover,started it up the engine is a little noisy when cold but once warmed up pretty much all you could hear is the injectors ticking. Everything under the cover looked new. The tensioner looked good. So I guess it must have been the ac compressor or the pulley thats making the noise. Thanks everybody for the help. 1 Quote Link to comment Share on other sites More sharing options...
1 Lucky Texan Posted December 15, 2015 Share Posted December 15, 2015 wow - glad that was it! Quote Link to comment Share on other sites More sharing options...
Bushwick Posted December 15, 2015 Share Posted December 15, 2015 (edited) My EJ22 isn't noisy when cold. And once warm, like yours you can barely hear the injectors. The noise you are hearing at start up might be a bearing in one of the pulleys. I remember one or 2 of mine were a tad noisy when cold after getting the car. I removed the pulleys, and they had no excess play (up/down in/out) meaning the bearings weren't shot yet so they were wiped down clean. Took some clean axle grease and applied to thumb, then pressed it in between the dust shield and bearing case on the sides, while spinning the pulley so it'd spread throughout the other needles, then excess was wiped off. There's a narrow window of when bearings can be saved. Once they start getting eaten up they are goners. Anyhow, put as much grease into them as possible, and they had a slight drag while spinning and felt tighter. They all went back to quiet regardless of cold/warm, and think engine has extra 25k miles since. Will definitely replace during next timing belt change, but was able to get a little more life out of them. Dunno if it's worth risking on interference engines though. The car was a complete unknown at the time and wasn't willing to dump too much into it until it proved to be a sound investment (it proved itself Edited December 15, 2015 by Bushwick Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.