Oil

[graham harvey]

Hi all,

I changed my oil last year to 5w40 and i have noticed that it is leaking alot more now. Would you recommend moving back to 10w40? The garage has advised that I have a leak from the front oil cooler and from an oil pipe in the engine bay. I will be doing a leak down test to see if a top end rebuild is required. It did have a rebuild to fix the original 964 issue but it has now done circa 150k miles.

What do you guys think re the oil?

 

[AVI_8]

If your cooler and pipe is leaking it won't matter what oil you're using it will still leak. I had to do my cooler last year, the only remedy is to change the parts unfortunately

 

[graham harvey]

Many thanks, will order the part. i think I will replace both coolers and pipes. There is some leakage around the actual engine but I think that is normal.

 

[Gordon Attar]

0W/40 and to a lesser degree 5W/40 are bit on the thin side, specially for the pre gasket cars as they do optimise any potential leaks When they do the pipe and the radiator suggest going back to 10W/40 as they will probably replace all the oil anyway.

 

[Melv]

10/40 recommended for our older engines....try Mobil Motorsport

 

[Dekker]

Both coolers??....lucky you. I'm replacing the oil pipe from the lower end of oil tank to the engine that lies fairly horizontal in the wheel arch because mine is sweating. I've also noticed that the flexible reinforced pipe from the bottom of the oil thermostat to the oil filter has a split in the metal clamp at the junction of rubber to hose union so will be replacing that also. I will check with other suppliers of this item compared to OPC prices as high pressure hoses are used in many industries, especially farm tools. As regards the oil, I think 5w-40 too thin for our engines and would not contemplate such a low viscosity regardless about what the official line is. This type of oil might suit the kettles and modern engines but ours need a higher grade and also we need oil that has the anti-wear additives for the friction type valve train. Look at the Mobil 1 Extended Life 10W-60 engine oil has been designed to help provide the extra protection that older engines can demand. It is suitable for virtually all types of older vehicles and operating conditions. and others like that.

 

[graham harvey]

thanks for the responses guys. I had thought a return to the 10w40 or similar would be beneficial. The car has only been using 5w40 for a year or so. I have replaced some of the pipes a few years ago so will replace the rest and the coolers. I have been thinking if a top end rebuild is on the cards but the rolling road is still showing very healthy figures. If a leakdown test proves all ok, is there actually a need for a rebuild? Before this issue there were only a few drops around the actual engine.

 

[Dekker]

ORIGINAL: graham harvey thanks for the responses guys. I had thought a return to the 10w40 or similar would be beneficial. The car has only been using 5w40 for a year or so. I have replaced some of the pipes a few years ago so will replace the rest and the coolers. I have been thinking if a top end rebuild is on the cards but the rolling road is still showing very healthy figures. If a leakdown test proves all ok, is there actually a need for a rebuild? Before this issue there were only a few drops around the actual engine.

If it ain't broke...........etc

 

[jamest]

ORIGINAL: Melv 10/40 recommended for our older engines....try Mobil Motorsport

Is Mobil Motorsport still available? I don't seem to be able to find it anywhere.

 

[iangray100]

As far I have seen on the web Mobil 1 15W-50 Motorsport has been discontinued so I have switched to Mobil 1 Extended life 10W-60. Check out www.opicoils.co.uk

 

[jamest]

Thanks Ian.

 

[jamest]

Interesting post by Opie Oils advising against the use of 10W60 at the end of [link=http://www.pistonheads.com/gassing/topic.asp?h=0&f=48&t=1124865&mid=14510&i=20&nmt=996+GT3+oil+reccomendations&mid=14510]this PH thread[/link].

 

[mcgc0]

Interesting PH article from Opie. On reading it makes sense. Starting my apprenticeship (decades ago!) big plant diesels were where I focussed. One of the things I took on board were oils and additives, or detergents rather. Diesel oils then used high detergent additives - high compression ratios, harder working engines blah blah... I ran for a while a completely rebuilt classic Ford engine on a purely high detergent diesel oil. Ideal then as it kept all parts nice and clean with low carbon/sulphur build-up etc. Starting with a non-high additive/detergent oil (mineral or most semi-synths) then switching many years later to a fully synth higher detergent oil 'flushes' away some of the deposits that actually help create seals between some non-moving surfaces. It used to be said that you could hear the difference if you switched with parts seemingly 'clattering' more. Thought this might be interesting guff to some anyway. My engine, like many probably, is a high miler. That there 10W60 Opie review is very relevant I guess. Too thick and and you risk a bit more local hot-spotting (more potentially with air cooled engines too). I remember reading that Porsche on some of the works engines actually opened up some of the oil-ways to improve flow. A too 'thicker' high temp oil isn't going to be as efficient through those oil-ways as something slightly less thicker. A 0W arguably is better then a 5W or 10W on cold starting. I believe a very important factor, despite what people forget (or even say today), is the old adage of letting the oil warm up first before engine loading. A low value cold start oil reduces any momentary 'dry running' which easily is one of the most damaging/wearing things that can happen. I always seem to end up full circle with this one with all the impassioned debates on this. I want a low cold start oil but not the synth diesel type (which most/all are). There are a couple semi-synths around of 5W40 but not on the Porsche A40 list but I might investigate these anyway. In the meantime my 140k is more than happy it seems on 10W40 Mobil for the time being - and using less oil than the handbook suggests! Marcus

 

[Steve Brookes]

ORIGINAL: jamest Interesting post by Opie Oils advising against the use of 10W60 at the end of [link=http://www.pistonheads.com/gassing/topic.asp?h=0&f=48&t=1124865&mid=14510&i=20&nmt=996+GT3+oil+reccomendations&mid=14510]this PH thread[/link].

I've just had the 10W-60 put in because the 15W-50 is no longer available. The car now feels down on power compared to before and was running noticeably hotter in traffic. i.e. the same effects as the Opie Oil article indicates. So, I'll be taking it out and putting something lighter in.

 

[jamest]

I have been using 10w50 but have just ordered Silkolene Pro-S 5w40 after speaking with Opie Oils. My car is on 97k miles with some minor leaks, am a little worried that the thinner oil is going to exacerbate these but figured I can live with regular oil top-ups.

 

[Dekker]

I wish I'd seen that thread as I've bought some 10W-60 for the current service. I hadn't realised that the difference between levels of viscosity were non linear. With Mobil continually reformulating their oils and making life difficult I assumed that it was a natural progression as they stipulate that this 10w-60 is the inheritor of the 10w-50 motorsport which has had such good reviews for air cooled Porsches. Back to the drawing board.

 

[Steve Brookes]

Well...I've just taken out the Mobil motorsport 10W-60 and put Fuchs Supersyn 5W-40 in. The engine is now back to where it was before the thicker oil went in. It's now eager and responsive again. Thank goodness this thread came up and the advice there in from Opie Oils. I wouldn't have thought in a million years that something as simple as the grade of oil could have an effect on the engine's performance.

 

[ras62]

Interesting reading Steve, your experience seems to bare out exactly the points made in the Opie piece. I will stick with 5w40!

 

[iangray100]

I've just taken out the Mobil 10w-60 as I noticed the oil temperature gauge ran cooler as per the artical which is not good on an air/oil cooled engine. I have refilled with Castrol Magnatec 10W-40 as the usual Mobil Motorsport has been dropped and immediately the oil warmed up so it's obviously taking the heat away for cooling more efficiently . I didn't notice a performance drop but I did notice the tickover was slower even when the engine was warmed up so turning the Mobil "jelly" was taking RPM !!!! Why has Mobil stopped the Motorsport version and replaced it with a non comparable version that's too thick with fundamental engineering consequences !!!

 

[Damen]

Try Castrol Magnatec 10w - 40. Has worked very well for me on road and track (plus Halfords currently have it in offer at £17.50 for 4 litres). Damen