What are the reasons for a creamy oil cap?

[joelk]

HI there,

I'm about to buy a 94 Ferrari 456 (lucky me I know)- but one I have seen had a creamy coffee like residue on the underside of the oil cap.

I heard this normally means there's a problem with the head gasget. Or - are there other possible explainations for this? (seeing it's a V12). The sales people suggested it was due to condensation build up as it had often been used for only very short journeys.

It's 94, with 37k and a FSH, last serviced at 31k.

Many thanks !

[deltaf]

Usually just a condensation build up. If you have any worries about head gasket problems, you can get a block test done on the coolant.
All this is, is a peice of equipment that has a carbon monoxide sensitve liquid inside it.
The radiator cap is removed and the block tester pushed into it and then a rubber eye dropper(large) is squeezed and it then bubbles the air/gases from inside the radiator air space through the liquid.
Any carbon monoxide in the coolant causes a color change.
The only way carbon monoxide can get into the coolant, is either a head gasket or cracked head or block.

As i said tho, its most likely just condensation caused by short start/stop type journeys.
Hope this helps.

[wedg1e]

Aye, and would you want a Ferrari that had been used for short, stop-start jurneys...

Ian

[rev-erend]

I would either walk away or if you are still keen then get a full report from a specialist on the car !!

Head gaskets & new heads will be very expensive on a V12 - could well be the reason the person is selling - as he might not have a warrenty !!

And if you buy then try to claim (assuming you buy a warrenty) - they will say no - as it's a preexisting condition..

[Mark Benson]

A quick and dirty check is to sniff the coolant - does it smell of exhaust fumes? (non-scientific version of deltaf's advice)

[pistol pete]

joelk said:

The sales people suggested it was due to condensation build up as it had often been used for only very short journeys. It's 94, with 37k and a FSH, last serviced at 31k.

Not serviced for 6k and used for stop-start/short journeys. -I dont like the idea of that on a car like that (performance/high maintanance, not cos its italian ).

Spending that kind of money I'd get a respected 3rd party or specialist garage to give it a thourgh check over for you -particularly compression test aswell as the coolant checks if the head gasket is potentially dodgy.

Pete

[jaydee]

Although it's a perfectly plausible explanation the thoughts of a Ferrari of that age that's only been trundling to Tesco are a)alarming b)improbable. I would hazard a guess that it's been in storage for a long time, with only an occasional run to keep the oil flowing.
There are loads of threads on 'cheap' (these things being exceedingly relative) Ferraris. Worth checking these out and talking to a specialist as there are numerous, and in one case (door/window problem) horrifyingly costly, issues with older 456s.

[boosted ls1]

Can you give it a really good thrashing to see what happens or stick it on a rolling road. It may be ok after all, you never know this could be the time to get some discount

[RichB]

joelk said:

I have seen had a creamy coffee like residue on the underside of the oil cap.

You may know this - the residue is oil and water emusified into a paste - rather like mayonaise or margerine i.e. oil and water. Rich...