Can I use a thicker oil?

aston

aston

The Torque Meister
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VOLVO and VW
Hi all, I have bought a bit of a Lemon, after all it's a VAG product so can be expected, One of the lemon problems is smoking at idle, which we think is more than likely oil passing past the piston rings.
Years ago the norm was to use a higher viscosity oil, But these days it is said engines are uptight and not so forgiving, However the smoke can be quite embarrassing.
the correct spec oil for the 3.0 tdi is 5w30, If I go for a thicker oil will it cause any probs, any idea what spec I can go to? Cheers all
 
I don't think this will necessarily fix the problem but you could go to 5w40. It's not a blocked PCV or EGR is it? This can cause high crankcase pressures which will force oil past the rings.
 
It's also likely to be valve stem seals.
If it smokes like a pig when first started, this can be an indicator to this problem. As oil trickles down into the cylinder when stood.
Tickover smoking is also a sign.
Yes you can run thicker oil, within reason.
What car is it?
Lucas heavy duty oil stabiliser is a much better option than just think oil.
It's worth mentioning that blocked oil galleries and tappet/cam jets can get blocked with black goo.
I would give the engine a damn good flush, redex or other fuel system cleaner, new filter and then add the oil and additive, and give it a long run to somewhere nice at around 3_4000 remember (motorway stuff)
Put redex in the plug holes over night too.
Sometimes heavy carbon deposits can induce oil consumption.
 
Sorry, also use a flushing agent in the old oil before you drain it.
Can't recommend lucas highly enough. No noticeable loss of mpg.
 
I've done some digging with this problem for you and a few people have suggested injector issues.

To diagnose this see http://wiki.ross-tech.com/wiki/index.php/3.0l_V6_TDI_(BKS/BMK/BUN) for tips.

If engine oil level is dropping then it is likely to be piston or valve leak. An oil stabiliser may help but these products don't generally do the turbo or oil pump much good. Most Audi's I've known are quite fussy on the type of oil used and clog up if you go outside of spec.

Make sure it's a good quality fully synthetic oil though, cheap oil is cheap for a reason. Ask oilman in our oil forum for guidance on this, he will surely have come across something suitable you can use.
 
VW 507.00 covers pretty much everything apart from the V10 PD TDi in the Touraeg and Phaeton. You can use a 505.01 5w40 I think but you forego the dubious privilege of extended drain intervals which 5w30 507.00 permits.

I'd avoid oil additives - they do indeed cause problems with turbochargers.

No plug holes here - this is a derv drinker.
 
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obi_waynne said:
I've done some digging with this problem for you and a few people have suggested injector issues.

To diagnose this see http://wiki.ross-tech.com/wiki/index.php/3.0l_V6_TDI_(BKS|BMK|BUN) for tips.

If engine oil level is dropping then it is likely to be piston or valve leak. An oil stabiliser may help but these products don't generally do the turbo or oil pump much good. Most Audi's I've known are quite fussy on the type of oil used and clog up if you go outside of spec.

Make sure it's a good quality fully synthetic oil though, cheap oil is cheap for a reason. Ask oilman in our oil forum for guidance on this, he will surely have come across something suitable you can use.
Click to expand...
Please explain turbo issues with additives. No logic I can think of???
 
Thicker oil flows more slowly. This reduces heat transfer away from the turbo. In exceptional cases this can cause the oil to overheat, thus sludging and block oil flow completely.

I'm happier with manufacturer certified synthetics. Especially with the PD engines and their outrageous prescriptive camshaft lubrication requirements. I don't think Aston's V6 is a PD - VW did us the grace of never fitting PD injectors to the V6 engines.

There's a bit of a myth about thicker oil being better or more protective. There was a time when, all other things being equal, that this was true. But the chemists are clever and synthetic oils now - even own brand ones such as Asda's - are very very good indeed. And priced attractively.

Diesel engines, especially, do not warrant a heavier grade of oil. This is due to an unfortunate but real side effect of diesel combustion: soot thickening. This, I think, is why most diesel engines are specified to use a 5w30 oil. There's more 'room' for some viscosity increase due to soot thickening before the oil fails to circulate properly.

Lucas' Oil Stabilizer is pushed (by Lucas) as a 100% petroleum product. To me this means that it employs no synthetic technology at all, ie. it's a 'natural' product.

I'd far rather have synthesized chemicals running around my engine.

Natural belongs on the plates of food I cook and serve to my family - and no, I haven't yet started adding Duckhams 20w50 to soups just yet, despite it's arguably appealing lime green colour :D
 
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^ What he said x2!

emmomojo said:
Please explain turbo issues with additives. No logic I can think of???
Click to expand...
Turbos pretty much cook the oil when you shut off. Few additives can cope with these high temperatures associated with the turbo and just break down or burn. This causes clogging, fouled oil flow through the turbo unit or other problems elsewhere with the now soiled engine oil.
 
Understood. Lucas synthetic is not affected by this, and modern water cooled turbos are way less prone to this now than pre water cooled units, and the old method of allowing the unit to cool first before shut down, by letting the engine idle for a while works wonders. Not many turbo owners do this sadly.
New Zealand law allows you to lock the old skylines and walk away from the car,engine running on an automatic timed shut down for this very reason. UK law prohibits this because of the laws vintage, where cars left running and unattended had a habit of jumping into gear and running away.
I think obi that there are additives and there are additives.
Dangerous ones for turbos are ones that contain ptfe, because when it gets very hot it breaks down to form an acidic compound.
Though modern day turbos, especially on diesel cars, this is a thing of the past.
 
HDI, lucas do a synthetic, and it doesn't "thicken" it adds elasticity in long chain polymers. I have used lucas and cannot fault it, apart from the cost mate.
 
aston said:
Hi all, I have bought a bit of a Lemon, after all it's a VAG product so can be expected, One of the lemon problems is smoking at idle, which we think is more than likely oil passing past the piston rings.
Years ago the norm was to use a higher viscosity oil, But these days it is said engines are uptight and not so forgiving, However the smoke can be quite embarrassing.
the correct spec oil for the 3.0 tdi is 5w30, If I go for a thicker oil will it cause any probs, any idea what spec I can go to? Cheers all
Click to expand...
I have a 99 toyota corolla and i usually use what my manual recommends which is 5w 30...on another note does anyone have any experience with check engine codes p0440,p0441, and p0446 and what they mean and any do it yourself fixes i like working on my car.....any response will be great.
 
The smoke is certainly not injectors (I've had them checked at great expense) It's not valve seals as no smoke at start up, I'll try a flush and thicker oil with the Lucas additive, Thanks all
 
Bore wear mate or a blocked breather. I would try blocked breather pipe first and cross your fingers and toes.
There is another method to extend engine life in older worn engines, without expensive machine shop expenses. It's called the evacuated sump(evacupan)method.
It's possible to do with some welding and common engineering skills. Without going to look, it's in a book I used to have about race engines by David Visard, commonly known as the Wizard to people of my vintage.
Basically, instead of the sump breathers feeding into the inlet side, you feed them into the exhaust instead (definitely after the cat!)
You need some 15mm steel tubing, some 15mm internal diameter silicone hose, and an anti backfire valve (though not really necessary on a turbo diesel engine)
The idea is that the negative sump pressure with the suction of the exhaust, "pulls out sump vapour and prevents the crankcase pressurising, which allows oil to pass worn cylinders. It's also good for economy and a few more ponys too, as it increases fuel octane efficiency by preventing contamination of the engine oil. It's lotts cheaper than hauling out the lump and paying for boring and new pistons etc.
 
It's when you get oil contamination in the cylinder, thus reducing the octane in the charge, due to the presence of the contaminant. This causes a drop in efficiency due to the slower burning time of the oil making for a poor explosion basically.
Old engines used to knock too.
Watch the beach racing or any two stroke bike race for this matter on the startinggrid line-up, every rider is revving the nuts off the bike to prevent this phenomenon occurring. They call it oil fouling. Two strokes run flat and lethargic until excess oil has been cleared through.
 
This is why shells opti max is a waste of time in anything but perfectly sound engines.
Shell claim more power and mpg due to higher grade, higher octane fuel.
 
Calorific value is the amount of energy per kg or litre. Tesco Momentum 99 does indeed have a 99RON rating, but has one of the lowest calorific values of any road fuel sold in the UK.
I completely agree with you that there's no point running higher octane fuel than the engine requires.
 
Re evacupan. Just remembered. The loss of the pressurised crankcase also increases hp due to the lack of pressure on the underside of the pistons (crankcase pressure) giving a mild turbo effect with a linear curve of gains along side revs. It will also prevents excessive oil consumption. This mixed with lucas will have it running like an old roller, if, it is "breathing heavy " due to worn bores.
 
I think it's a fairly crude arrangement (Austin-Rover through and through) with a vacuum pipe connection (from the inlet manifold) to the crankcase, via a filter to avoid sucking in too much junk. Basically just puts slight negative pressure inside the crankcase. Obviously not possible with a diesel engine - no throttle equals no vacuum.

The engines are AR's 8 valve 1.6 and 2.0 units, respectively. Nothing remarkable about either of them. Nor the cars into which they were bolted.
 
Take a look. Old hat stuff in old race engine builders. It's called prudent economic common sense. And btw thick oil also works wonders on certain applications.
 
Thicker oil will work in some cases, I did this with a 1986 Montego which was getting a bit smokey at 110,000 miles. Not sure I'd use it in modern engine configurations though.
 
It's about perception. My renault suggestions on oil are a 10 w 30 or a 10w40 but that is for UK. It's a very poor guideline. It's perfectly feasible to use a 0w 30 or 0w 40 because this spec supercedes the last. In very cold climate this would be the ONLY option due to the cold start viscosity improvement.
In hotter climate like southern Italy for example an oil such as 0-10 50 would be more suitable, due to better protection in the hot running conditions. Of course the quality of a fully synthetic over a straight mineral is vast, but more importantly, thin stuff is great if you service the car at the correct intervals.
I drive hard, and that's why I add lucas oil stabiliser to all my engines and transmission. It's more motorsports spec protection. And I service the car accordingly. Slow drivers should stick to recommend service interval schedules, harder driving requires more frequent oil and filter changes.
I once remember a dry sump 1.6 Peugeot 205 rally car of a friend of mine doing 3 very severe events in the little car and it hadn't lost a single bhp from when it was last put on the same rollers (Dyno) because it was on Mobil 1. Expensive though because I think it ran about 20 litres capacity, ouch, expensive oil change. Well. That's motorsports!
 
Agreed - there are far more factors than just viscosity grade. Different ambient temperatures are probably less of a problem than they once were as engine operating temperatures are much more closely regulated now than they once were.

I follow the variable service intervals to a point, but I do prefer to keep to a maximum of about 12000 between oil changes.
 
Subaru used to have an optional
88 degree (standard) and a hotter one for winter, 92 if I remember, as did many other manufacturers.
 
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