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Re: Clacking from head/block

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>> >>> >>>> I have a 1996 Outback that has not been driven for 4 years, and has not >>>> been started for ~2. We changed the oil ast week, charged the battery and >>>> started it up. There was a clacking noise that seemed to be coming from >>>> the passenger's side head, or close to the block, that smoothed out >>>> somewhat when we revved the engine but never went away, and got worse at >>>> idle. >>>> >>>> I think it's a sticky valve and am hoping it will free up as the car is >>>> run more. Any ideas? >>>> >>>> This is a 1996 Outback with the 2.2L engine. >>> >>> >>> Added rec.autos.tech... >> >> Possible cam-belt tensioner? IIRC , it's partially an oil-pressure >> hydraulic setup, would make sense with the conditions. >> >> It's always a gamble, but I'd give it a heavy dose of one of the "thin" >> (distillate type) "engine cleaner" additives. Give it a few >> long/hard/hot runs to let it work 200-500 miles or so, a good excuse to >> go on a mountain-pass road trip. > > >That's what I was thinking. Trying 1/2 QT of Marvel Mystery Oil for this >change and the next one. But it's still not on the road yet, the E-Brake >is frozen and the rotors and pads are no longer separate items... >
20 minutes running with MMO will LIKELY solve the problem if it is a gummed up lash adjuster.
Reply to
clare
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Piston slap is pretty easy to diagnose in its early stages. You will hear piston slap most prominently when the engine is dead cold and under a load, and it will diminish as the engine warms up. Is this what the OP was experiencing?

Reply to
ben91932

Hard to say. This engine, if I am interpreting it correctly, should be a 2.2 litre SOHC H4 boxer arrangement.

I have been curious about these for a long time, but have no experience with Subaru. They are supposed to be good strong engines.

I'd like to hear any comments about this setup.

Reply to
hls

i experienced this for years with honda engines, and was particularly disappointed when my new 2000 civic started doing it after only 30k miles.

but recently, i tried an oversize oil filter on a high mileage civic because the motor was particularly noisy, because i figured there was nothing to lose from better oil flow. i was stunned at the result - "piston slap" almost entirely gone when cold. looking back on the 2000 civic, the noise started round about the same time i transitioned to the new smaller honda filter pattern - it would have been interesting to see what would have happened if i'd gone back to the old size honda filter. since the old noisy civic discovery, i've tried this on my accord too

- same noisy "cold slap" went away using a larger filter.

bottom line, these new smaller "more efficient" filters may be fine in terms of performance when the oil is at full working temperature, but i believe their cold flow characteristics are inferior and restrict flow. it follows that the noise we're therefore hearing is actually bearings, not pistons.

i don't know if a larger filter [with larger medium area and thus less cold flow restriction] is available for subaru, but if it is, for

Reply to
jim beam

i'd like to hear your comments on logical thinking with regard to engine coolant color.

Reply to
jim beam

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