deposit on rocker clips?

"goose" > wrote in message
...
> Hello all
>
> I've just changed the tappet cover gasket on my 1986 525e;
> I noticed that the clips that go over each rocker arm
> (flimsy looking metal thing) each seemed to have a
> light-coloured deposit (creamy).
>
> Any idea what this could be?

Condensation?
The so called mayanaise.
Mike.

On Thu, 07 Oct 2004 23:40:17 +0100, Mike G wrote:

>
> "goose" > wrote in message
> ...
>> Hello all
>>
>> I've just changed the tappet cover gasket on my 1986 525e; I noticed
>> that the clips that go over each rocker arm (flimsy looking metal thing)
>> each seemed to have a light-coloured deposit (creamy).
>>
>> Any idea what this could be?
>
> Condensation?
> The so called mayanaise.

Actually mayonaise is closer than you might think. Both what you are
seeing and mayonaise is just an emulsion of oil and water (well not solely
water in mayonaise, but that's beside the point). It suggests to me that
the car isn't being driven hard enough, often enough, to bring the engine
up to full temperature long enough to boil out moisture that collects in
the oil.

In non-winter conditions it takes something like 15-20 minutes of 60MPH or
better driving to bring everything up to normal running temperaures. Yeah,
I know the temp gauge will indicate normal much sooner than that, but
that's only the coolant temp in the block. The oil pan and contents aren't
at full temp until much later and then only when the engine is working
much harder than it does at low speed driving. And once at full running
temp it takes a while more to boil any moisture out of the oil.

A small amount of moisture in the oil such that you see some emulsion on
cooler parts of the engine (unually just found under the valve cover)
isn't necessary terribly harmful. However that moisture isn't just water.
It also contains some acids from the combustion blow by, which is where
the moisture normally comes from. And it's the acids that break down the
oil and that's not good. The nicest thing you can do for any engine
(other than good maintainance and timely oil changes) is a good 30 minute
or so run at highway speeds at least once a week.

All of that assumes that you don't have an inexplicable loss of coolant.
If you are loosing coolant with no obvious leaks it is possible that it is
winding up in the oil. That's not good at all any would require immediate
investigation and repair.

--
The instructions said to use Windows 98 or better, so I installed RedHat.

Hello all

I've just changed the tappet cover gasket on my 1986 525e;
I noticed that the clips that go over each rocker arm
(flimsy looking metal thing) each seemed to have a
light-coloured deposit (creamy).

Any idea what this could be?

(Learned *one* important thing tonight: when working
at night in the summertime, close the garage doors
before you pull off the tappet covers. It took me
the best part of an hour to fish out three moths
who suicidally flitted around the light hanging
over the cylinder head)

goose,
the *moth* man prophecy

Mike G wrote:

> "goose" > wrote in message
> ...
>
>>Hello all
>>
>>I've just changed the tappet cover gasket on my 1986 525e;
>>I noticed that the clips that go over each rocker arm
>>(flimsy looking metal thing) each seemed to have a
>>light-coloured deposit (creamy).
>>
>>Any idea what this could be?
>
>
> Condensation?
> The so called mayanaise.

What exactly is it, then? Oil + condensation? Does
it possibly indicate engine damage/wear/condition?

goose,
TIA

"goose" > wrote in message
...
> Mike G wrote:
>
> > "goose" > wrote in message
> > ...
> >
> >>Hello all
> >>
> >>I've just changed the tappet cover gasket on my 1986 525e;
> >>I noticed that the clips that go over each rocker arm
> >>(flimsy looking metal thing) each seemed to have a
> >>light-coloured deposit (creamy).
> >>
> >>Any idea what this could be?
> >
> >
> > Condensation?
> > The so called mayanaise.
>
> What exactly is it, then? Oil + condensation? Does
> it possibly indicate engine damage/wear/condition?

Usually indicates the car is not used for long enough or gets hot enough to
evaporate the internal condensation that occurs with any engine as it cools
down.
Look at the outside of an engine after a cold night. It's usually wet.
Similar condensation occurs within the engine.
Short runs simply emulsify that condensed water with oil to form the
mayonaise.
Over time it simply builds up. Too much and the oil performance will be
affected.
I've seen cars so bad that the dipstick only shows creamy emulsified oil.
A good long run, with the engine at full temperature will clear it,
providing it's not caused by a failed head gasket, or similar.
Mike

Are the cams slightly worn out ? Is the amount of mayonaise rather important
? Was the cover stained inside ?
If yes, you've probably a crack in the head.
If they don't appear, take care, they could become quickly.
It could also be condensation. I don't believe so.
Keep watching it at least once a week for several months through the oil
opening, especially after long and intense heatings. Put a finger inside,
look at it.

I Had this problem on my first 316 (1985). When the engine was very_very
hot, water drops were sourcing below the head of a bolt.
The thing slowly increased for months until I was able to see the water
coming out.

The head was dismounted at the dealer's, put in a liquid and the crack
traced under UV. It was located between a head bolt hole wall and the water
cavity.
Because of the tight contact due to the pressure of the head bolt against
the aluminium, the crack was almost sealed most of the time.
I had to replace the head (of course), the camshaft and the crankshaft
bearings as well.
BMW took it under guaranty albeit the car was 4-year old and the guaranty
period over.

Good luck



"goose" > a écrit dans le message news:
...
> Mike G wrote:
>
> > "goose" > wrote in message
> > ...
> >
> >>Hello all
> >>
> >>I've just changed the tappet cover gasket on my 1986 525e;
> >>I noticed that the clips that go over each rocker arm
> >>(flimsy looking metal thing) each seemed to have a
> >>light-coloured deposit (creamy).
> >>
> >>Any idea what this could be?
> >
> >
> > Condensation?
> > The so called mayanaise.
>
> What exactly is it, then? Oil + condensation? Does
> it possibly indicate engine damage/wear/condition?
>
> goose,
> TIA (

"Simon Cussonnet" > wrote in message >...

<snipped description of problem: creamy deposit in head>

> Are the cams slightly worn out ?

yes, very slightly, I believe (due to being very
afraid of adjusting with too small a clearance).

> Is the amount of mayonaise rather important
> ?

I dont know, which is why I'm humbly asking assistance :-)

> Was the cover stained inside ?

no.

> If yes,

"yes" to which one of the above questions? I've answered
"yes", "dont know" and "no" ;-). I suspect that you mean number
3 only.

> you've probably a crack in the head.
> If they don't appear, take care, they could become quickly.
> It could also be condensation. I don't believe so.
> Keep watching it at least once a week for several months through the oil
> opening, especially after long and intense heatings. Put a finger inside,
> look at it.
>
> I Had this problem on my first 316 (1985). When the engine was very_very
> hot, water drops were sourcing below the head of a bolt.
> The thing slowly increased for months until I was able to see the water
> coming out.
>
> The head was dismounted at the dealer's, put in a liquid and the crack
> traced under UV. It was located between a head bolt hole wall and the water
> cavity.
> Because of the tight contact due to the pressure of the head bolt against
> the aluminium, the crack was almost sealed most of the time.
> I had to replace the head (of course), the camshaft and the crankshaft
> bearings as well.
> BMW took it under guaranty albeit the car was 4-year old and the guaranty
> period over.

Oh dear! Now you've frightened me. This is an ancient car with no
warrantee(sp?) at all; A crack in the head of this car is a death-knell
for the entire car.

>
> Good luck

thanks, and thanks for your reply as well,
goose

Jim Levie > wrote in message >...
> On Thu, 07 Oct 2004 23:40:17 +0100, Mike G wrote:
>
> >
> > "goose" > wrote in message
> > ...
> >> Hello all
> >>
> >> I've just changed the tappet cover gasket on my 1986 525e; I noticed
> >> that the clips that go over each rocker arm (flimsy looking metal thing)
> >> each seemed to have a light-coloured deposit (creamy).
> >>
> >> Any idea what this could be?
> >
> > Condensation?
> > The so called mayanaise.
>
> Actually mayonaise is closer than you might think. Both what you are
> seeing and mayonaise is just an emulsion of oil and water (well not solely
> water in mayonaise, but that's beside the point). It suggests to me that
> the car isn't being driven hard enough, often enough, to bring the engine
> up to full temperature long enough to boil out moisture that collects in
> the oil.

That could be; I vary rarely drive the car hard and I almost *never*
exceed 2000rpm. Once a month (sometimes twice, like this month) I drive
down to the coast. Its a 600km trip (one-way), but I generaly keep
to around 100km/h - 110km/h, which equates to around 2000rpm - 2200rpm.

Is that not hard enough? The car has /very/ long legs, even in auto form
and I find that to maintain 3000rpm I've got to keep to a speed of around
165km/h.

>
> In non-winter conditions it takes something like 15-20 minutes of 60MPH or
> better driving to bring everything up to normal running temperaures. Yeah,
> I know the temp gauge will indicate normal much sooner than that, but
> that's only the coolant temp in the block. The oil pan and contents aren't
> at full temp until much later and then only when the engine is working
> much harder than it does at low speed driving. And once at full running
> temp it takes a while more to boil any moisture out of the oil.
>

Like I said, this car is geared for very low rpm's. I could possibly keep it
in third (or something) at 120km/h (national speed limit), which would
keep the rpm's up, but the engine just doesn't feel like it is working
when you cruise in third gear at 120km/h (it feels like it is under
no strain at all i.e. not working as hard as it would be if you
were in final gear).

> A small amount of moisture in the oil such that you see some emulsion on
> cooler parts of the engine (unually just found under the valve cover)
> isn't necessary terribly harmful. However that moisture isn't just water.
> It also contains some acids from the combustion blow by, which is where
> the moisture normally comes from. And it's the acids that break down the
> oil and that's not good. The nicest thing you can do for any engine
> (other than good maintainance and timely oil changes) is a good 30 minute
> or so run at highway speeds at least once a week.
>
> All of that assumes that you don't have an inexplicable loss of coolant.

Not that I've noticed (check about once a month).

> If you are loosing coolant with no obvious leaks it is possible that it is
> winding up in the oil. That's not good at all any would require immediate
> investigation and repair.

<grin>So, you reckon a good, rapid drive to the coast and back on my next
trip should do the trick?

"But officer, the car *needs* to go that fast, honest!" :-)

goose,
bail me out, please :-)

"Mike G" > wrote in message >...
> "goose" > wrote in message
> ...
> > Mike G wrote:
> >

<snipped description of problem>

> > >
> > > Condensation?
> > > The so called mayanaise.
> >
> > What exactly is it, then? Oil + condensation? Does
> > it possibly indicate engine damage/wear/condition?
>
> Usually indicates the car is not used for long enough or gets hot enough to
> evaporate the internal condensation that occurs with any engine as it cools
> down.
> Look at the outside of an engine after a cold night. It's usually wet.
> Similar condensation occurs within the engine.
> Short runs simply emulsify that condensed water with oil to form the
> mayonaise.

I do roughly 20km to work each morning in peak traffic, and 20km back
home each evening in peak traffic. Could that be "Short runs"?

> Over time it simply builds up. Too much and the oil performance will be
> affected.

Should I rather change the oil more frequently?

> I've seen cars so bad that the dipstick only shows creamy emulsified oil.
> A good long run, with the engine at full temperature will clear it,
> providing it's not caused by a failed head gasket, or similar.

I do long runs once (sometimes twice) a month, but the car
never gets above 2200rpm (unless its for a minute or so while
I'm climbing a hill).

thanks
goose,

"goose" > wrote in message
om...
> Jim Levie > wrote in message
>...
> That could be; I vary rarely drive the car hard and I almost *never*
> exceed 2000rpm. Once a month (sometimes twice, like this month) I drive
> down to the coast. Its a 600km trip (one-way), but I generaly keep
> to around 100km/h - 110km/h, which equates to around 2000rpm - 2200rpm.
>
> Is that not hard enough? The car has /very/ long legs, even in auto form
> and I find that to maintain 3000rpm I've got to keep to a speed of around
> 165km/h.

No, that is nowhere near hard enough. You will have carbon deposits in your
combustion chamber and the mayo you have seen. Wring it out once in a
while... get it to where it's indicating normal operating temperature, and
drop a gear or two. Get the revs up near the redline and let off the gas to
let it engine brake a few times while maintaining the same gear. You might
even see a white puff of smoke when you let off, that's burnt carbon (good).
You don't need to go fast to do this, only to rev hard. That's what your
transmission is for. Do this for 5 or 10 minutes, get things really
ticking in there. BMW motors are literally designed to run like this.

Once every couple of weeks should be enough.

If that was your cracked block in the other post there though, I might have
to take that back. You could cause a catastrophic failure of a weakend area
by doing the above.

Also, I've seen cases where the accumulated carbon was so bad, that the
first hard run caused a valve to explode (piece came out) because of the
very poor heat transfer caused by the excessive carbon. This happend when
she went up a long hill once while in a very rare hurry on a car she never
drove hard any other time. So you might want to work up to full heat
cycling or perhaps do a wet soak first.

-Russ.