Cetane rating

[Billman]

What would be better?

A cetane rating of 45 from a station that does not sell much fuel.

OR...

A rating of 42 from a station that would appear to be in a better location, selling more fuel?

Let's hear it...

[catmandoo]

a cetane of 50 something in europe.what does this country have against diesels.friend of mine is in germany and people over there will kill for a diesel.look who makes diesel cars for sale here mercedes and vw,oldsmobile did but converting a gasser to diesel does have it's limitations.i think if they put a little more effort into it they could have had a great engine.i still have a 4.3 diesel and it just purrs and 36 mpg,the one thing i gotta say is somebody finally makes a diesel motorcycle,too bad it's just for the military,i'd buy one in a heartbeat.

[gwaidman]

Billman, go with the station the sells more volume, as you will have 'fresh' fuel for your truck. You can boost the numbers (42) with Power Servivce additive (or others. A bad tank of fuel will quickly ruin any performance advantage you may be getting from the other station.

[lupey6.5]

what applications did the 4.3 serve? is it turbo? whats up with it? you know. or is that another forum?

[rjwest]

Do a search on Oldsmobile diesel , there ia a forum
out there somewhere that had some very interesting
info, on the olds diesels

[eracers999]

I would try the 45 cetane fuel and if i liked it i would go out of my way to get it.
The 45 cetane fuel would in my opinion be of better quality.
Kent

[DmaxMaverick]

Billman

I don't know how it is where you are, but in CA there are no "old" underground fuel tanks anymore. All the tanks have been replaced due to some EPA (or something) legislation. There are some stations that pump fuel from above ground tanks, and I stay away from them. The underground tanks, being of newer design, and just plain new, are a pretty safe bet for good fuel. If I had a choice here like yours, I'd go with the higher cetane fuel and watch it closely for a while.

The other thing is, how did you come by the rating? Was it just the word of the attendant, or a posting somewhere? If it's posted, it's probably reliable. If it's "word of mouth", verify before believing. In either case, you wouldn't be out of line to ask for proof. Most fuel stations have no idea what cetane is, let alone how to keep Diesel safe. The best thing would be to catch the tanker when it arrives and talk to the driver. He should have a manifest that lists the actual fuel going into the tank.


catmandoo (sorry, a little off topic)


....oldsmobile did but converting a gasser to diesel does have it's limitations. This is a myth. I hate it when I hear it. The Oldsmobile Diesel was never converted from a "gasser". The engine was designed from the ground up as a Diesel engine. It was a joint venture between GM and Detroit, which was owned by GM at the time. It did have some issues, but was basically a very good engine. It would have done much better if it weren't so "foreign" to the market. It was also the basis for the 6.2L, 6.5L and even the Duramax in some respects. Now, the Navistar 6.9L and 7.3L engines were real gasser conversions, believe it or not. The reason that the GM 350/5.7L Diesels seemed to be gasser conversions was due to the application. The engine was designed from the beginning to be used in existing GM cars and pickups. The engine it was replacing was a GM V-8, so naturally, it would end up similar. Other components of the engine fell into line with existing components already in use by GM, and naturally became part of it. This also made the engine more familiar to tech's which made service less painful, in most cases. If anyone has been inside both a 350/5.7L Diesel and a GM gasser, they'd know that the similarity ends with appearance. The block and internal components are very different, similar only because they are both V-8's. I could go on and on, but I'll spare you my rambling. Some of it, anyway.

Cheers

[Billman]

As far as I know, NY State law requires fueling stations to post octane/cetane ratings on all pumps.

The 45 rating that I found is a Citgo station that is very close to my house. The problem is the pump locations. I have a hard enough time getting to the pump with a CC Dually. Never would an OTR truck get to the pump, or even a medium duty truck. This is why I believe the volume of diesel they pump to be pretty low. Some of the other local stations (Hess for one), has very accessible pumps to all kinds of trucks. But their ratings are lower. Mostly 42, but I have seen 40. The New Jersey Turnpike(Sunoco) is 40 IIRC. They must pump HUGE quantities.

I'm just curious as to everyone's opinion on 'Fresh fuel' vs. 'Ratings'.

[DmaxMaverick]

All pumps have a gross volume meter on them. This is like an odometer in a vehicle and starts a 0 when the pump is new, and is not re-setable. You could go right to the horses mouth and watch these for a couple weeks and see just how much fuel is actually being pumped. Bear in mind that a higher volume pump will normally have a larger storage tank. The key is not necessarily how much the pump is pumping, but how often the tank is refreshed. You may also find on the tank cover the tank volume, so you could do some simple math to compare the two.

For example, if station "A" has a 3,000 gal. tank, and it takes 3 days to pump 3,000 gal's according to the meter, then it is a 3 day replenishment, or 1,000 gal's a day. If station "B" has a 30,000 gal. tank, but takes 15 days to pump 30,000 gal's, or 2,000 gal's a day, the better bet would be to go with the smaller station "A" even though they pump less gross fuel. All things are not as they seem, so getting a first hand look is the only way to tell what's really going on.

You could get lucky and find a station attendant that knows what is really happening. Around here, outside of the large truck stops, all I find is counter jockeys that order fuel when someone complains that the pump is running real slow, or stopped. It's a PITA, but I find out when the truck shows up and get fresh fuel. I do wait several hours after the truck leaves to be sure that anything that might get stirred up while filling the storage tank settles. If you have a station that has a quick replenishment rate, the risk of stirred up sediment is less. Also check that there is a filter at the pump, either inside the casing, or out. Stay away from above ground tanks if at all possible. They are more prone to water and biological growth due to unstable temp's. The temp swing with underground tanks tracks the seasons, not the days, so condensation is nearly nonexistant.

You should also consider using an additive if there is any doubt of fuel quality, but that's for another thread.

Cheers

[Billman]

Years ago when I worked in a Gas Station, I had to take the readings off the pumps occasionally. The numbers were in view for everyone to see. Not so anymore. Everything here in NY is digital. I haven't seen meters on pumps for quite a few years. They are probably located behind the 'counter'.

But my favorite part of your response was the part about an attendant that "knows what is really happening".

They don't speak English... Well, maybe a few words... Super, Regular, Marlboro...

[TurboDiverArt]

I would suggest using whichever your truck likes. Personally I would probably go with the higher volume dealer. I just asked the Hess station that I fill up at what the blend is. He said he didn't really know, only that the supplier said it was winterized and to tell his customers that there was no need for fuel additives. I asked about when he gets deliveries. He gets a delivery every week and it is typically 10,000 gallons, sometimes a little less, sometimes a little more but pretty high volume. I tend to believe the volume number as every time, and I mean every time I have filled up (once a week) there is always either someone else already there or by the time I finish someone else pulling up to the pump. I'd say probably half the time there are 2 trucks filling up at the same time. I've never seen an 18-wheeler fill up but usually box trucks. Many times during the week when driving by there is someone at the diesel pump.

I'd love to figure out a way to find out what the actual blend is during the winter. Probably doesn't matter as the truck runs great, no smoke or sputters and mileage is where I would expect it to be.

Art.

[eracers999]

I dont know if anyone even read my post about testing cetane on 03-24-04 .
Its a really useful and fun tool to have and would clear up many questions about fuel quality so that you wouldent be just taking (sombodys word for it).
Kent

[Billman]

I did read your post, Kent. I then started doing a search to try and find out more about it.

Just got busy and couldn't continue...

How does it work?

[eracers999]

Billy;
You take a fuel sample off your fuel bleeder valve in front of the eng into a suitable container, anything that will hold a pint of fuel. The tool is a hydrometer type of a tool and has a color coded graph on the float. You suck up some fuel into the tool holding it up straight and see whear the float winds up.
If the float is in the red cetane is 38 to 40 (poor quality)
If the float is in the yellow cetane is 41-45 (medium quality)
If the float is in the green cetain is 46-50 (high quality)
The temp of the fuel should be around 60 degrees f.
You all may find it interesting the affects that some additives have on the test.
Kent Moore says this tool is not to be considered scientificly accurate. My take on this is that you can definatly be shure that the cetane levels are within the above posted numbers. Scientific would be exact. With this tester you can come real close, in my opinion. If anyone purchases this tester from Kent Moore it is FRAGILE, made of glass.
Good day to all.
Kent