Hi. I was wondering if a thin layer of foam is normal or to be
expected at the top of the oil in the reservoir after say a 10 mile
run. I am ppositive they are tiny bubbles and not water or other
contamination. It's a 92 brave one with a merc 454, drive oil was
just changed. Thanks.

On May 12, 2:19*pm, wrote:
Hi. *I was wondering if a thin layer of foam is normal or to be
expected at the top of the oil in the reservoir after say a 10 mile
run. *I am ppositive they are tiny bubbles and not water or other
contamination. *It's a 92 brave one with a merc 454, drive oil was
just changed. *Thanks.

Not sure, but I wouldn't expect any. After the drive has sat idle for
a while slowly open the lower plug and let just a little lube out. If
there is any water it will come out here.

On May 12, 3:29*pm, "John" wrote:
wrote in message

...

Hi. *I was wondering if a thin layer of foam is normal or to be
expected at the top of the oil in the reservoir after say a 10 mile
run. *I am ppositive they are tiny bubbles and not water or other
contamination. *It's a 92 brave one with a merc 454, drive oil was
just changed. *Thanks.

What brand of oil did you put in it? *Shouldn't foam but maybe detergent?
Is this the first time you ran it? *Maybe just bubbles in because the drive
was not completely full? *If you got the drive hot and now has sat for
awhile the reservoir probably went down a little so now the drive is
completely full. *Run it again and see if you still see bubbles.

Quicksilver Hi-Perf, Merc Hi-Perf in the past when available. Not the
first time it's happened. I does happen more so early in the season
after I change the oil so I figure it's because of a little air
trapped in there making its way out. It happens fairly consistently
throughout the seasons though. You mention detergent, would that be
detergent in the oil? I even wonder if it could be vibration against
the transom shaking things up. I'm just worried about heat being the
cause. I've been reading about the drive showers people are
installing now for cooling so I wonder. Thanks

wrote in message
...
On May 12, 3:29 pm, "John" wrote:
wrote in message

...

Hi. I was wondering if a thin layer of foam is normal or to be
expected at the top of the oil in the reservoir after say a 10 mile
run. I am ppositive they are tiny bubbles and not water or other
contamination. It's a 92 brave one with a merc 454, drive oil was
just changed. Thanks.

What brand of oil did you put in it? Shouldn't foam but maybe detergent?
Is this the first time you ran it? Maybe just bubbles in because the drive
was not completely full? If you got the drive hot and now has sat for
awhile the reservoir probably went down a little so now the drive is
completely full. Run it again and see if you still see bubbles.

Quicksilver Hi-Perf, Merc Hi-Perf in the past when available. Not the
first time it's happened. I does happen more so early in the season
after I change the oil so I figure it's because of a little air
trapped in there making its way out. It happens fairly consistently
throughout the seasons though. You mention detergent, would that be
detergent in the oil? I even wonder if it could be vibration against
the transom shaking things up. I'm just worried about heat being the
cause. I've been reading about the drive showers people are
installing now for cooling so I wonder. Thanks

Probably is air then. Why didn't you say that it happened every year? I
thought the marine products did not have detergent because of the proximity
to water.

I have a drive shower. No harm in having one but no one has proven or
disproven them. It's not a new idea. The top of drives does get hot. Take
a fairly decent run and then jump in the water and feel the top of the
drive. A drive shower does make them cooler. But differentials in rear
wheel drive cars get pretty hot too and they have no significant cooling
except air.