supermarket v shell/BP diesel

[Bungo]

Always used bio, car loves it.

[skyship007]

Originally Posted by Bungo

Always used bio, car loves it.

Are you using a 50/50 mix or pure stuff ??

This article is worth reading about Bio diesel and winter operations:

http://articles.extension.org/pages/...weather-issues

Love this part:
A diesel fuel’s cold-weather characteristics are measured by the cloud point (CP), the cold filter plugging point (CFPP), and the pour point (PP).

What I think they need to figure out for a diesel with an unheated fuel filter, is not the CP, or the CFPP, BUT the FFUP (Final forked up point)!

Most of the local farmers I know are still using a 50/50 mix (Good to minus 12c) rather than normal diesel. Their exhausts smell like burnt chips, but it keeps the fuel system real clean and has great lubricity.

[Bungo]

I use 100% (properly made stuff) but when nippy I put a couple of gals of dino into it.

[tt82]

I have found that my economy suffers when using Tesco. Also going of my Fuelly stats, the cars on board computer is generally 1-2mpg optimistic when using Shell/BP, when using Tesco it is generally out by a margin of 4-5mpg. So there is a difference and I would only really use supermarket fuel if there was some sort of offer on that covered the decrease in mpg.

[GrahamBrown1]

Skyship is right, my v70 only did short trips for 3 years and has only ever ran on supermarket fuel in our ownership. injectors on the d5 are good for at least 150k normally so I'm sort of just assuming that has caused one of the injectors to fail.

[dannydazzler]

Shell fuel better more refined

[Backhill1]

Originally Posted by skyship007

Not sure, but it's normal for one of the cylinders to run cooler than the rest and that injector will be the first to gum up when short tripping with cheap fuel too often.
Oddly enough if you blow out (or even wear out in some cases) the injector tips using El-cheapo fuel filters, they all get trashed together.

Half of all the injectors sent to an injection system service center only need cleaning, which could have been done without removing them, although if you wait until one is bad enough to cause a misfire, it migt take several goes to clear the gum.

Supermarket fuel is the same price as Aral (Owned by BP) fuel in Germany, so I just stick to that chain.

Why would one cylinder run cooler that another and cause gumming?
as its a common supply and return line like central heating?

[skyship007]

Originally Posted by Backhill1

Why would one cylinder run cooler that another and cause gumming?
as its a common supply and return line like central heating?

It does not relate to the temperature of the fuel, but more to the temperature of the injector and that depends mostly on cylinder head temperature. Very few engines have cylinders that all run at the same temperature and if you short trip with cheap fuel gum forms in the injector just after shutdown.

One other point about supermarket fuel is that the more expensive top of the range diesel from major oil companies like BP or Shell does contain more solvents and fuel detergents designed to keep the injectors clean. If you look at the price difference between using a top of the range fuel and the cheaper supermarket fuel, it is enough to make using a fuel additive economic.
Gum forms very slowly, so it only really means using one can of additive every service interval.
Info on gum deposits:
http://www.marship.eu/low-sulphur-fu...ectors-to-fail

You could write a book about why most engines have a cold cylinder or two. Often it results from a combination of deposits in the cooling system and varnish forming around the top end of the oil system, so even when the designer gets it right, owners that fail to change the coolant (Or use tap water to top up), or do too long an oil change interval still cause long term issues with uneven CHT's.

[skyship007]

Originally Posted by dannydazzler

Shell fuel better more refined

Don't know much about their fuel as I use Aral, which is owned by BP, although Shell have a very good reputation for accurate advertising, so if they say it's cleaner and has better additives, it will be true.

Shell make by far the best engine oils in economic terms (Cost vs performance). I've tested a number in my diesel and the results of using Shell Ultra 5w40 (A3/B4) were almost the same as using Liqui Moly Synthoil High Tech 5w40, which is an expensive German standard full synthetic.
Mobil 1 turbo diesel truck 5w40 (C3) was terrible and Castrol Edge is just too expensive to even think about.

[Fearone]

Originally Posted by skyship007

Don't know much about their fuel as I use Aral, which is owned by BP, although Shell have a very good reputation for accurate advertising, so if they say it's cleaner and has better additives, it will be true.

Shell make by far the best engine oils in economic terms (Cost vs performance). I've tested a number in my diesel and the results of using Shell Ultra 5w40 (A3/B4) were almost the same as using Liqui Moly Synthoil High Tech 5w40, which is an expensive German standard full synthetic.
Mobil 1 turbo diesel truck 5w40 (C3) was terrible and Castrol Edge is just too expensive to even think about.

Can you please tell me how you tested the oil? In what way was shell better than mobil etc?

I like to use a good quality oil but struggle to tell much difference tbh.