General: mayo on the oil filler cap - Roger Jones
I'm looking for a W126 300 SE and I've been to see two today. Both have mayo on the oil filler cap, one more than the other. I've seen comment somewhere that it doesn't necessarily mean a failing/failed head gasket and that it can simply be evidence of condensation because of lack of use. What say you, fellow Backroomers -- all better informed than I am on such technical matters.
General: mayo on the oil filler cap - Stuartli
Some general advice found that may ease your fears:

"Open the oil filler cap on the cam cover. Only oil should be present - if there is any cream coloured gunge present then water has found its way into the oil system, possibly due to a blown head gasket. If there is just a little gunge, it could just be caused by the car not being used much recently, particularly if the weather has been cold and the car has not been driven on long journeys. Check the dipstick too. Hopefully all the oil will be relatively clear indicating a recent oil change."

"I've had the muck on the filler cap on a few cars and it was always moisture in the head caused by condensation rather than the gasket."
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What\'s for you won\'t pass you by
General: mayo on the oil filler cap - Stuartli
Many years ago I use to find that cleaning out the breather pipe helped to stop the buildup; modern oils don't seem to produce the same result on the cap or, at the least, very little.
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What\'s for you won\'t pass you by
General: mayo on the oil filler cap - Aprilia
The M103 engine is not particularly prone to condensation. I can't recall seeing this on M103's I've worked on. It could be innocent though, or it could be a sign of trouble (although these engines are not known for HGF).

IMHO, once you've found a car you're really interested in I would get it checked by a local Unipart "used car check" centre - costs only £99. If you buy a 300SE with hidden problems it will cost more than the car is worth to fix.
General: mayo on the oil filler cap - Roger Jones
Thanks, Aprilia.

Don't worry, my mechanic will give it a good go-over, and he's already intimately familiar with the 103 engine. Both cars have been standing quite a while; oil on both dipsticks looked fine; and the mayo on the better one was but a small fraction of that on the weaker one.

I'm inclined to pursue it, as the bodywork on the car is the best I've seen, with no sign of corrosion in the familiar W126 weak spots, although there are one or two tiny pockmarks elsewhere -- hardly surprising given the age of the vehicle. If I do acquire it and the head gasket does go, I reckon on having figured that eventuality into the purchase price. The vendor doesn't seem to have much technical awareness.

As a W124 owner, I'm well aware of the costs of maintenance and repair. My approach to it is to get it done properly by someone other than an MB dealer (lower cost, greater competence), change oil frequently, and treat the engine as the wonderful complex beast that it is (hence my recent installation of the engine pre-heater).
General: mayo on the oil filler cap - storme
i still wouldn't trust it

i drive to work .its 4 miles away,not chance to warm up...
and NONE of my cars have ever ever had any mayo...i think this condensation excuse is total tosh...

my wifes cars probably does 3 miles a day and her OLD punto dont have ANY sign of mayo....alto i do change the oil every 6 months..
dont believe it,dont trust it




.

\"dont shoot the messenger\"
General: mayo on the oil filler cap - mfarrow
i still wouldn't trust it
i drive to work .its 4 miles away,not chance to warm
up...
and NONE of my cars have ever ever had any mayo...i
think this condensation excuse is total tosh...


Well lucky you, but it depends on engine. I can drive 50 miles in my Ford in the winter and still get some mayo left under the filler cap. Before you ask, no, it definately does not use any water, oil, or any other fluid which it isn't suppose to.

Condensation exists. Period.
General: mayo on the oil filler cap - Victorbox
Same here. My wife's 2002 Corsa has has a little mayo from new. I was quite shocked the first time I topped it up during the running in period. I put it down to short, cold journeys and everything at the top of the engine now appearing to be made of plastic rather than metal. Car is fine. My Cav's metal filler cap gets so hot by comparison no condensation could linger there.
General: mayo on the oil filler cap - scotty
Yep, my Omega had slight mayo when I bought it over 2 years and 35,000 miles ago. Had an RAC check at the time which said just condensation due to low use at the dealers. Given the time and mileage since I think he was right.

Les
General: mayo on the oil filler cap - mjm
On all 3 of the BX s I have owned the oil filler pipe ran down the front of the engine. This pipe, and the associated bits always had mayo present. It was part of my service routine to clean the affected bits up. The last BX was a 16valve, I always did 12/13 mile runs in it. I sold it when it had 143000 miles on the clock. The engine was still as sweet as a nut. The oil filler on my Xantia is on the cam cover, it,s hotter there, no mayo present.
General: mayo on the oil filler cap - Dynamic Dave
On my last Vectra and current one, I get a small amount of mayo on the filler cap in winter when only doing the short 6 mile journey to and from work. I generally take it for a blast at weekends to get rid of it.
General: mayo on the oil filler cap - blue_haddock
my old Pug 309 GTi occasionally got gunked up through only being used for short journeys, give it a bit of a run with plenty of revs and it soon dissappeared.
General: mayo on the oil filler cap - matstro
I had a look at a 10 year old T5 today. After a test run, only about 3 miles, the temp gauge was well up and the exhaust was quite steamy. Looked at the cap and there was more than a trace of this creamy stuff. So, watching this thread with interest!
General: mayo on the oil filler cap - Doyle
Noticed this www.andyspares.com/discussionforum/topic.asp?TOPIC...9 at another forum yesterday.

Doyle