Which oil should I buy?

[2cv-lamont]

hi i am going to do a service on my old 2cv which had nearly 100000 miles, after reading the posts i am a bit confused could somebody advice me on whether get comma multigrade 20w50 or comma xt2000 15w40 semi synthetic?
any advice would be appreciated
thanks in advance

[Geoff Ryall-Harvey]

I've always used oil intended for diesel engines.

[QFAD]

Geoff,

Funnily enough I have used diesel oil for both petrol and diesel engines. When I was a service manager with a mixed fleet I rang a well known oil manufacturer's tech dept and explained my situation. The response was use diesel oil as it's spec exceeded that for petrol engines. Not a surprise when you consider the compression ratio and high torque loadings etc of a diesel engine.

Our Guzzi bikes ran on 15W40 diesel oil for 17 years - Lin's T3 850cc clocked up 90,000 miles and my 1000cc G5 clocked up over 100,000 miles before we sold them for a newer model.

The key point is to change your oil - as most 2CV based kit cars are only used in the summer months and do not do that many miles per year, you still need to the oil at least once a year even when below the recommended replacement mileage - the manual says 3000 miles or every 3 months; whatever comes first. Folk tend to forget the 3 months part....

If your 2CV based car is put to bed at the end of the summer I would suggest changing the oil then, rather than leaving the bearings etc soaking in the old contaminated oil (combustion byproducts etc) over the winter.

[Ken Hanna]

Just wondering which manual that was, as I've never yet heard of a recommendation to change engine oil every 3 months?

However, I do frequently notice the sticker fitted to the base of the windscreen of 1980s cars by Citroen, which advised an engine oil change
every 10,000 km...

Ken
(4.5 litres of 10W/40 of semi-synthetic @ £9.99 from Home Bargains these days; just fill the trolley and head for the checkout.
Seems to suit the 250,000 mile engine in the old Dyane just fine... )

The key point is to change your oil - as most 2CV based kit cars are only used in the summer months and do not do that many miles per year, you still need to the oil at least once a year even when below the recommended replacement mileage - the manual says 3000 miles or every 3 months; whatever comes first. Folk tend to forget the 3 months part....
If your 2CV based car is put to bed at the end of the summer I would suggest changing the oil then, rather than leaving the bearings etc soaking in the old contaminated oil (combustion byproducts etc) over the winter.

[QFAD]

Hi Ken,

It was from the Haynes 2CV manual - I do not have an original Citroen manual, so I'm happy to be corrected. The point I was trying to make was to undertake regular oil changes and mileage alone is not the sole criteria for changing the engine oil. I think circa 3000 miles or, if less mileage is covered, then annually is prudent - especially when you can source decent oil at relatively low costs.

I hear many folk talking about synthetic oils and the common assumption you can extend oil change intervals to well above the recommended mileages/timelines. I appreciate there are many factors impacting upon the degradation of engine oils, but the nasty byproducts of combustion seem to be forgotten when discussing synthetic oil longevity.

Our old Guzzi's had the oil changed every 2000 miles - but I admit the oil was free - perk of the job at the time.

[QFAD]

Hi Ken and all,

Ref the query regarding my source for the '3 months' time oil change interval - the book 'How to restore Citroën 2CV, Enthusiast's Restoration Manual' by
Lindsay Porter also repeats this instruction. It also includes this comment: The service schedule shown in this chapter is mostly based on the recommendations of 2CVGB, the ... It's based on the servicing needs of a typical 602cc-engined 2CV.

Chp 3 Servicing and maintenance: Service B: Every 3 months or every 3000 miles/5000 km. Repeat Service A, plus the following: Replace engine oil and filter.

It does discuss the different options for oil type/grade - 20W20, 10W40 etc...

Of course the above is caveated by how reliable you consider the Haynes and the restoration manual to be. I know Haynes are not highly regarded, which is why I bought the other manual. I have to say it has proved to be very helpful, assisting my learning curve.

What are your thoughts....

[Ken Hanna]

Hi, have a look at page 20 ( & onwards) in this free download of the Two Horse Stables' "Maintenance Handbook for Citroen Twins".
http://www.classic-citroen-tech.co.uk/m ... ndbook.pdf
Written by someone who understood A series cars, instead of cribbing some nonsense from Haynes...
Ken
( Note that this was written prior to the introduction of unleaded fuel.
If it was updated now, I'm sure that the recommended interval for valve clearance checking/adjustment would be much shorter.
For what it's worth, I check them during every oil change, which is carried out at 6,000 mile intervals, as recommended by Citroen on a windscreen sticker fitted to late 1980s cars. )

Hi Ken and all,

What are your thoughts....

[QFAD]

Hi Ken,

Thanks for your link. I had not heard of it before your post - at last a reliable source of information. I'm suprised it has not been mentioned before - having just said that I expect I will be proved wrong

[Geoff Ryall-Harvey]

Great link Ken - thanks.

Frequent oil changes never did any harm. Not much oiled needed for an A series engine anyway. I buy the 25 litre drums from Costco. Plenty of changes in that.

[Jimmy Cooper]

Interesting stuff. A good friend and ex chief aircraft engineer used to say that the specification of modern car engines can utilise the semi or fully synthetic engine oils advantages, but that engines designed in the sixties would perform best on the modern equivalent of their original spec oils as used back then and it was a waste of money using fully synthetic oil on part worn engines.
He has a point as the modern machining of engines mean they are fit to run 'out of the box'. You don't see "Running In; Please Pass" signs in the back of car windows anymore.