Clacking from head/block

On the boxer engine, I found this:

http://townhall-talk.edmunds.com/dir...ew/.f119459/10

They claim the slap IS typical of this boxer engine.

On 09/26/2011 11:45 AM, ben91932 wrote:
>
>> I wouldn't discount the possibility of piston slap.
>
> 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.

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 <$7,
it's worth trying. for honda, wix #51344 does the job nicely.


> Is this what the OP was experiencing?


--
nomina rutrum rutrum

On 09/26/2011 12:13 PM, hls wrote:
>
> "ben91932" > wrote in message
> ...
>>
>>> I wouldn't discount the possibility of piston slap.
>>
>> 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?
>
> 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.

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


--
nomina rutrum rutrum

On 9/26/2011 12:13 PM, hls wrote:
>
> "ben91932" > wrote in message
> ...
>>
>>> I wouldn't discount the possibility of piston slap.
>>
>> 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?
>
> Hard to say. This engine, if I am interpreting it correctly,
> should be a 2.2 litre SOHC H4 boxer arrangement.

Sorry, this is most likely the DOHC version.

All "H" engines have a propensity for piston slap, it's just the way it
is, but decent designs almost negate it.

Piston slap in a Subaru H4 or 6 is rare, but does happen enough to be
aware of it.


--
"**** this is it, all the pieces do fit.
We're like that crazy old man jumping
out of the alleyway with a baseball bat,
saying, "Remember me mother****er?"
Jim “Dandy” Mangrum

"Nobody > (Revisited)" > wrote in message
...
> On 9/26/2011 12:13 PM, hls wrote:
>>
>> "ben91932" > wrote in message
>> ...
>>>
>>>> I wouldn't discount the possibility of piston slap.
>>>
>>> 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?
>>
>> Hard to say. This engine, if I am interpreting it correctly,
>> should be a 2.2 litre SOHC H4 boxer arrangement.
>
> Sorry, this is most likely the DOHC version.
>
> All "H" engines have a propensity for piston slap, it's just the way it
> is, but decent designs almost negate it.
>
> Piston slap in a Subaru H4 or 6 is rare, but does happen enough to be
> aware of it.


This engine is a 2.2 litre,op says. Offered that year we
Engine 2.2L SOHC 135 hp (101 kW) H4
2.5L DOHC 165 hp (123 kW) H4


So, it probably wasnt a DOHC.

Piston slap in the Subaru H4 is ANYTHING BUT RARE, of this era.
They are known for it, apparently. It is documented that the slap,\
though loud and unnerving, normally does not limit the engine life.

On Mon, 26 Sep 2011 11:45:59 -0700, ben91932 wrote:

>
>> I wouldn't discount the possibility of piston slap.
>
> 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?

Nope. Idle was the loudest, and it got smoother and a little less
pronounced when run at higher RPMs. Car is not on the road right now.


Definite clicking noise, like a sticky lifter makes.

On Mon, 26 Sep 2011 14:15:36 -0500, "hls" > wrote:

>On the boxer engine, I found this:
>
>http://townhall-talk.edmunds.com/dir...ew/.f119459/10
>
>They claim the slap IS typical of this boxer engine.
Piston slap is generally a light "double knock" that generally
changes with load - just tap the accellerator and let off and it
should change pitch and "quality" or intensity - while a lifter is a
heavier "single knock".

Also, piston slap will be engine speed or double engine speed (double
or singlee knock), while valve will be half engine speed. Piston noise
will generally pretty well dissapear when the engine is warm - and
will not be there on a warm restart. Valve noise may go away when
warm, but usually gets intermittent first - and it often will do a
little "tap dance" at idle even if it has quieted down at fast idle -
and it will often be there on initial hat restart as well.

Not sure about the Sube, but some engines with an oil leak from the
oil gallery will drain the oil from the lifter gallery when shut off,
allowing the lifters to start dry and will take time to pump up and
quiet down. Same problem with some cheap oil filters - the orange ones
I don't need to bother naming are NOTORIOUS for having bad
anti-drainback valves, and OFTEN cause engines to be noisy on a cold
start. VERY often, just replacing the Orange crap with a quality
filter like a WIX /Dana / Etc stops the cold-start noise.

Another test is to remove one plug wire at a time until you find the
one that eliminates or greatly changes the sound. If you find one, it
is a piston (or rod) noise - not a valve....