frag Posted December 6, 2003 Share Posted December 6, 2003 Under the hood for some minor things, here's what I discoverd. Not sure it was'nt already there and I just did'nt notice... When idling (and when idling only) I hear somethink sounding like a knock (nothing resemblic the tic or clac of valves) with a frequency of about 1/4 the idle rpm (700rpm) (3 times a second approx.) When I put my hand on the top of the engine I feel something like if someone was hitting the top of the engine from inside with a rubber mallet. No other symptoms. And all of this disapears above 1,000 rpm. If I had a bad crank bearing, would'nt the imbalance be felt side to side and not up and down due to the boxer configuration? And would'nt the sound be worst above idle rpm? I feel ridiculous asking this but would someone with a 2.2L put his hand on the top on the engine (any part will do, power steering reservoir, alt, intake, I feel it everywhere) and tell me if he feels the same thing. Thanks in advance. Quote Link to comment Share on other sites More sharing options...
PAezb Posted December 6, 2003 Share Posted December 6, 2003 A timing belt tensioner going bad? Quote Link to comment Share on other sites More sharing options...
Nuwan Posted December 6, 2003 Share Posted December 6, 2003 frequency 1/4 of idle? just a guess but that would narrow it down to an issue with a single cylinder (1 out of 4).... it may not be firing properly, so check the plugs for anything out of the ordinary. Quote Link to comment Share on other sites More sharing options...
frag Posted December 6, 2003 Author Share Posted December 6, 2003 Timing belt tensioner going bad? Possible. I recently (june I think) replaced the timing belt, took all the precautions with the tensioner (compressed it even slower than indicated) but I remember I had to nudge the piston back out on the tensionner pulley when removing the pin. Did'nt make anything of it at the time (seemed like a temporary binding), but i's haunting me right now. But would it give the engine this vertical jolt I feel when I put my hand on the top of the engine and that feels like a rubber mallet blow? Thanks for the input. Quote Link to comment Share on other sites More sharing options...
PAezb Posted December 6, 2003 Share Posted December 6, 2003 If you're not getting any warning lamps, my best guesses would be the belt tensioner. But if it's more of a vertical knock, maybe even a broken motor mount....?? These are just guesses... waiting for heavies on this forum to chime in. Quote Link to comment Share on other sites More sharing options...
northguy Posted December 6, 2003 Share Posted December 6, 2003 PM alias 2035. He may well be able to diagnose your problem. Quote Link to comment Share on other sites More sharing options...
frag Posted December 6, 2003 Author Share Posted December 6, 2003 Thanks all. As soon as temperature permits, i'll follow all your leads. I'll even make a vacuum test and listen carefully with my stetoscope all over the engine. Weird thing is the idle is stable and silk smooth almost all of the time, making me think it's mechanical more than electrical or fuel related. But I'll check spark and plugs anyway. Quote Link to comment Share on other sites More sharing options...
alias20035 Posted December 7, 2003 Share Posted December 7, 2003 Your old EJ22 has hydraulic valve lifters that in some cases will only click at idle. Usually this is a sign of a bad oil pump or oil pump seal, but in most cases just clogged lifters. I find that adding a can of Wynn's Valve Quiet can help alleviate this problem. But I don't think lifters are the problem. Piston slap can exhibit the conditions you describe, and it is typically isolated to cylinder #4. If the sound/vibration goes away once the engine warms up, odds are that it is piston slap for which you really can not do anything about. I am concerned about your tensioner, especially since you had to pry the piston out when you changed the timing belt. This is not normal, or at least it has never occured to me in the 20 or so timing belts that I have changed. Everytime I pulled the pin the tensioner promptly expanded. Typically a bad tensioner will cause the belt to slap around at idle and it will stablize a bit at speed. This is a dangerous condition that has killed more than a few engines (like 6 WRC cars in one season a while back!). You can remove the right and left timing covers and note if the belt is slapping around, in some cases the belt is so slack it slaps the covers and makes a mark. Check the tensioner for signs of a leak, and for signs that it has moved out of position. Sometimes the bolts holding the tensioner will be loose, they should not be. I would remove the tensioner and place it in a vice and compress it, and note the amount of force required to compress it, and the rate that it expands. I have worked with many of theses and I am sure I would note one that is out of wack, but most Sube owners have no or little experience with tensioners, so I don't know how much success you will have by testing in this manner. You should also verify that the belt is still correctly aligned (note the crank pulley/timing cover TDC mark and the camshaft pulley alignment marks). Also check the idler pulleys and belt for damage. Crank bearings are a possibility, but usually the problem worsens with engine speed. Oil leaks from either the front or rear crank seals usually accompany a bearing failure. The only bearing failures that I have seen were the front bearing failing due to a loose accessory pulley. The EJ22's don't have many bearing or connecting rod issues. A misfiring cylinder is also possible, check the vacuum lines, plugs, wires, etc. Sometimes a clogged injector will cause some issues, so if you can't find anything else run some injector cleaner through. Quote Link to comment Share on other sites More sharing options...
DerFahrer Posted December 7, 2003 Share Posted December 7, 2003 Do not worry about anything internal. If you had a bad bearing, it would knock continuously, the frequency increasing with engine speed. The knocking would not go away... Get this. I was fearing the same thing, I had a knocking noise that would occur after giving it gas then letting off. Guess what it was?? Bad water pump. The bearing came loose and the pulley was wobbling... It sounded much more serious than it was...:-p Quote Link to comment Share on other sites More sharing options...
alias20035 Posted December 7, 2003 Share Posted December 7, 2003 Yep, the water pump would be good place to look for a problem, especially if it is the original. As a precaution I always changed my water pump every timing belt change, but I could get them for less than $50 which made it an easy decision economically. I am not sure what to do with my 01 Outback with its 168,000 km timing interval, should I just wait for the timing belt, or take it off next year when I hit 100,000km? Odd's are that the pump will easily last the 168K. When you have the timing cover off you should be able to see a wobbling water pump. If not you will have to pull the crank pulley and center timing cover off for a more extensive inspection. My 85 GL made a knocking sound from its water pump, I was barely able to hear it over the clacking lifters. It knocked long enough for me to say "what the heck is that" and then it self destructed. The pulley had loosened up causing the water pump bearing to fail. My big problem was finding a water pump for a US market GL in Canada, turns out there are five or more water pumps for the GL that have very slightly different pulley spacings, depending on which type of A/C system was used. I had to bring in a part from Vermont. Quote Link to comment Share on other sites More sharing options...
Setright Posted December 7, 2003 Share Posted December 7, 2003 Frag! I understand your worry. Every time "Scoobes" makes a new sound I start to panic and horrible thoughts of valves and con-rods flying through the air fill my mind. HOWEVER! My car is nearly 14 years old, and has 186k miles on the odo, so a few odd sounds are to expected. I reassure myself by pressing the accelerator and feeling the boxer pull hard and listen to the induction roar....nope, can't be anything wrong with an engine that's as willing as this! I will feel up the engine tomorrow some time, and get back to you on the rubber mallet thing Quote Link to comment Share on other sites More sharing options...
Setright Posted December 8, 2003 Share Posted December 8, 2003 Okay Frag, I just felt around my idling engine - much to the dismay of people passing by on the sidewalk! - and can't say that I feel anything like a rubber hammer pounding. However, it does make a sound similar to what you describe, off hand I would fear for main bearings on an inline engine, but I think what we are hearing is exhaust pulses. I suppose the long pause between them on a boxer can make them clang in the "empty" two-into-one pipe. Try to listen to warmstart at this address: http://www.geocities.com/vik2r/Sube/mp3 You should be able to hear the clonk/clang/knock during the idle periods. This recording was made over two years ago, and at roughly 120k miles. My EJ22 is now at 186k miles and sounds the same. Quote Link to comment Share on other sites More sharing options...
Soup Posted December 8, 2003 Share Posted December 8, 2003 My 2000 outback made the same sound, I wasn't sure if it was normal, so I took it to the dealer, at 75k, it's still under warranty. They replaced the timing belt and tensioner, they said the tensioner was leaking. Hope this helps Quote Link to comment Share on other sites More sharing options...
frag Posted December 8, 2003 Author Share Posted December 8, 2003 Thanks very much to all. Most of your posts are conforting. Will be doing a battery of tests as soon as possible (cold and snow right now and the closest private garage I can use is out of town) and will keep you posted. P.-S. And a special thank to Setright for having put his hand on his idling motor, courageously disregarding public opinion. Quote Link to comment Share on other sites More sharing options...
remarcable Posted December 8, 2003 Share Posted December 8, 2003 In case anyone was looking for a parts source, I just ordered a new water pump from 1stsubaruparts.com for $68.96. It's for my 99 outback. It was about $20 cheaper than the nearest dealer. Quote Link to comment Share on other sites More sharing options...
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