Ian A

Hi all

I may be overreacting, but I'm becoming increasingly worried by the following:

2000 miles ago I had a complete top-end overhaul, and all was well until recently. I did a round trip of around 130 miles, and then didn't use the car for a week or so. Next time I started the car and pulled it out of the garage, the smoke coming from the exhaust was so dense I could barely see into the garage the car had just come out of! After 5 minutes it eventually cleared up.

Hoping it was a 'one-off', I used the car as normal (low mileage trips). However, the next time I travelled a long distance - 200 miles - and garaged the car, it began smoking again for 5 minutes then cleared again when started.

I have been told (and I'm no techie) that due to 964's having a "Dry sump", oil can settle and be burnt when the engine first fires up. I'm not sure of this explanation, but it sounds rational enough.

The question is, is this normal behaviour? and if not, is there anything I can check to rule out possible problems?

The oil level indicator shows 'full' when on level ground (i.e. it points to "2:00pm") so could it just be overfull? If so though, why would it only start doing it now and not after the overhaul took place?

Sorry for all the questions, but I unfortunately am a worrier by nature

Thanks in advance for any help

Ian

1990 964 C4, 80k miles (LHD import)

johnfm

OVERFILL !

It is possible that on the longer journeys, the oil gets nice and HOT. It expands and overflows into the intake sytem when you park it up. When you start it, it burns oil, hence the smok.

WHen you say your oil gauge is full (ia at 2 o'clock) is this with the engine idling and with a hot engine or does it indicate at this level with a cold engine?

With the engine hot (ie temp gauge at about 9 o'clock) there is no need to half the oil level over half way - you must allow for the expansion of the oil when it gets hot.

Hopefully, this is the problem, otherwise you may have valve or ring problems which are more costly!

Have you taken back to the garage that did the work??

Ian A

thank you for your speedy response John

At idle, with a nice and hot engine, the oil level still indicates the 2pm position. I know the gauge isn't faulty too because it does drop and dip under certain driving conditions.

Hopefully your suspiscion about overfill will be accurate, although the guy who maintains the car for me did the refill when the engine work took place 4 months ago - which is why I'm confused that it hasn't happened earlier.
Ah but, the car *did* have a new oil return pipe (metal pipe in RHS rear wheel arch behind the wheel) fitted a month or so ago - maybe it was refilled at that point to replace the pipe?

Thanks again for responding though - I feel a little better now

Ian

johnfm

Ian

drain some oil from the car - loosen (do not remove) the crankcase drain plug and drain about a litre or so. Then warm it up and check the level.
IF it was an overfill, you may have some cleaning of the air intake system to do....

Ian A

Ok will do that - and thanks again for the help