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snapper
7th February 2010, 10:55 AM
Hello fellow members....after reading a lot of threads and doing some research i have found that blending would be my best option, due to the fact that getting enough waste oil, storage and time is limited.My question, is it a good idea to put in a helton duel coil heat exchanger(room is limited) with a shut off vavles for the heater when not using veg/diesel mix. Thanks:)

Tim-HJ61
7th February 2010, 12:10 PM
Hello fellow members....after reading a lot of threads and doing some research i have found that blending would be my best option, due to the fact that getting enough waste oil, storage and time is limited.My question, is it a good idea to put in a helton duel coil heat exchanger(room is limited) with a shut off vavles for the heater when not using veg/diesel mix. Thanks:)


Short answer is yes. A heater tap on the inlet feed of the Helton will do the trick. Using a heater tap with cable attached means you can turn it off from the drivers seat.

Longer answer is that unless you have already bought your Helton, then you'll find a more common heat exchanger is a 30 plate flat plate heat exchanger as they are found to be more efficient.

One of the up sides of blending is, depending on the blend, then you don't need to heat i.e. thin the blend at all.

We'd be happy to advise you directly on your options if you let us know your engine and vehicle model and the blending plans you have. You may not need any heat exchanger.

However if you fit one, then you are significant step towards a two tank setup that most people end with anyway.

Tim

snapper
10th February 2010, 10:14 PM
Thanks for the advice......snapper

Nuddy
11th February 2010, 10:43 AM
I do not believe it is necessary ( regardless of being an often preached veg mantra) to have a valve on the coolant for running Dino. Many vehicles like Peugeot, Citroen and Merc all have fuel HE's built into their systems designed to stablise the fuel temp (up or down) to coolant temp.
I believe Nuddy did some tests a while back that showed on his stock system the fuel temp was reaching over 100oC and if memory serves right, that was on a patrol as well.

This being the case, Having dino running through the HE will not cause and appreciable loss of lubricity of straight dino and may in fact be a help if you have a vehicle with a fuel system that picks up so much extra heat in the way it is set up.

If you are only thinking mainly of when you run out of oil, then a couple of litres of veg added to a tank of dino would well and truly render any concerns of lubricity a non event. Just keep 20 L or so aside to add to a tank of dieso.


Actually I think it was on the troopy.

Heat exchangers work in both directions. That is they bring the fuel closer to coolant temp. This may be heating the fuel or it may be cooling the fuel.

My opinion is that you don't want a tap on your HE system as you want it to work full time on whatever fuel you are using. When it is cold it is better to have your distillate at coolant temp. When it is hot your distillate may be getting quite a bit hotter than coolant temp before it gets to your HE and the HE will cool it down towards coolant temp which would be beneficial.
The current ULSD distillate is short on lubricity, regardless of its temp, due to the low sulphur content. Fuel manufacturers add 2% biodiesel to compensate and reckon that is sufficient, even when the distillate gets up to or over 100oC. IMO it would be wise to add a little more than 2% of good clean veg oil (or 2 stroke oil) to more than compensate for the lack of sulphur. This would be even more important if you don't have a HE to cool your fuel.

mixelpix
14th February 2010, 10:16 PM
IMO it would be wise to add a little more than 2% of good clean veg oil (or 2 stroke oil) to more than compensate for the lack of sulphur. This would be even more important if you don't have a HE to cool your fuel.

Howdy Nuddy,

It is not that sulphur provides lubricity to the fuel, it is that the processing by which ultra low sulfur diesel fuel is refined which makes it less lubricious. In the U.S. our ASTM (the commercially available stuff) ULSD already has significant lubricant additives to account for the result of this extra refining. Along with anti-static, anti-gel and anti-icing additives there are a whole host of compounds which comprise ULSD fuel.

I've heard it recommended that older IPs might benefit from the addition of 10W-30, ATF, biodiesel, etc. when considering the wear score marking tests and such when the IP wear and tear from ULSD fueling is compared to LSD and regular ol' D. This is also only something I have seen reportedly tested on Mercedes Benz Diesels of the 61x engine era (As reported in the M-B Club of America's magazine, The Star - note: not actually an M-B organization tho they are endorsed by MBUSA)

Best.

Tony From West Oz
14th February 2010, 10:32 PM
Yet those IPs are the least likely to be affected by poor lubricity fuel, they are lubricated by engine oil, not the fuel.

It should be tested on Bosch, Stanadyne and Lucal/Delphi/CAV IPs as these are all lubricated only by the fuel.

Regards,
Tony

froggo
14th February 2010, 11:23 PM
Hi mixelpix,

in old toyotas like mine the rubber seals in the ip required sulphur to keep them intact.

Once the low sulphur diesel was introduced the pre 1996 diesels that relied on sulphur to maintain gaskets started to shrink and leak. The option was to rebuild with viton seals.

My inline ip is lubed by engine oil and has mainly standard gaskets. There are several rubber gaskets that must be viton and suitable for Low Sulphur Diesel.

God bless froggo.

mixelpix
16th February 2010, 08:05 AM
Yet those IPs are the least likely to be affected by poor lubricity fuel, they are lubricated by engine oil, not the fuel.

It should be tested on Bosch, Stanadyne and Lucal/Delphi/CAV IPs as these are all lubricated only by the fuel.

Regards,
Tony

Is that so? While I would never dispute conventional wisdom :rolleyes: I thought all Bosch IP's were lubricated by both - oil on the bottom and fuel on the top end? LOL - goes to show what I know! The ones of my vintage (61x series 123's) are, but I dunno about all contemporary Bosch Diesel IPs. You can even see the soft line which delivers the oil and which the fuel in my '78.

Either way, it still holds true that sulphur itself does not provide lubricity, the process of removing it from ULSD removes the lubricating compounds otherwise available in LSD. To be sold commercially in the states, ULSD must meet lubricity standards (among others) and lubricating compounds have been added to make this so. That ULSD is a little dry compared to older fuel stocks is, however, a reality for old diesel owners. Well, I should say, owners of older diesels, LoL...

Another caveat with old fuel systems, of course, is that the extra solvency of neat biodiesel will melt a lot of the seals and gaskets. Sure have on a lot of old Benz with pumps that no longer hold... and hippies stranded on the side of the road :p

Best.

mixelpix
16th February 2010, 08:07 AM
Hi Froggo,

Thanks for the 411 :D

As the "new" owner of an "old" 1986 F250 6.9L V8 I am proceeding very cautiously with my fueling adventures.

Best.