Archive for March, 2010

Diesel VW Vanagon T3 Coolant Hoses – Part Three – Heater Hoses

March 9, 2010
Click to Enlarge

Click to Enlarge.

All Vanagons, diesel or gas, use the same heater core.

But once again, the ’82 hoses are different, as the heater shutoff valve is located under the dash, behind the glove box close to the heater core.

’83 and later Vanagons put the shutoff valve under the floor.

See Part One – Diesel VW Vanagon T3 Coolant Hoses – Engine Compartment – for details on how to read the information below:

(23) Heater Core
* ALL 251-265-303C

(9) Heater Hose (Feed) Front Heater Control Valve to Heater Core
NLA 82CS 251-265-053 (valve under dash)
* 83CS+Later 251-265-053C (valve under floor – could be cut to fit 82CS.)

(10) Heater Hose (Return) Heater Core to Adapter Fitting.
* ALL 251-265-054A (under floor)
Note:
my ’82 has both connections under the dash, and used the shorter (NLA) 251-265-053 for both feed and return, as both (9) and (10) are similar at the heater core end.

(11) Heater Hose (Feed) Cylinder Head to Front Heater Control Valve – 3900mm
NLA 82CS 251-265-055B
* 83CS+Later 251-265-055F
82 DIY:
The ’82s have 5/8” hose the entire length, except for a 1” connection to the cylinder head. Alan Felder from the Diesel-Vanagon yahoogroup suggests splicing standard 5/8” heater hose to a Gates 19663 hose (NAPA NBH11663) , which has a 1” end and a 5/8” end and is about 43” long. (Gates 18965 – NAPA NBH10965 also has a 1” to 5/8” reduction but is only 35” long). At $215 (list price 02/2010), the stock hose is pretty spendy.

(15) Heater Hose (Return) From Front – 3530mm – Connects to 3-Way Hose (6)
* ALL 251-265-057 (available but discontinued)
82 DIY:
if this isn’t just a $225 (list price 02/2010) length of 5/8” hose, I don’t know what is! Most folks recommend about 30 feet of 5/8 hose to replace the stock heater hoses.

Previous: Diesel VW Vanagon T3 Coolant Hoses – Part Two – Radiator Hoses

Next: Diesel VW Vanagon T3 Coolant Hoses – Part Four –  Expansion Tank

Not surprisingly, the 1982 Diesel Vanagons have a unique radiator, as gas Vanagons were still aircooled.  The next year, everyone go the same radiator, gas or diesel.  '82s also have a metal additonal metal feed pipe leading to the top of the radiator from the long underbody coolant pipes.  '83s also share the smaller (1.25”) diameter metal coolant pipes, while later gas Vanagons moved to larger (1.5”) diameter plastic coolant pipes.

(Radiator)
NLA 82 CS 068-121-253A  (CS >>24-C-175 000)
* 83CS+Later 068-121-253E (CS 24-D-000 001>>)

(8a) Radiator Feed Hose from Pipe. (not 82)
* 83CS+84?? 251-121-083G from small diameter (metal 1.25”) pipe.
* late CS 251-121-083H from large diameter (plastic 1.5”) pipe.

(9) Radiator (Feed) from Front Pipe & to Front Pipe from Rear (small diameter metal 1.25”) Feed Pipe. (82 only)
* 82 N900785.02  32x4x70mm (2.75" – need two - 82s have an additional front metal pipe for the radiator feed)
DIY: 1.25” heater hose.

(10-10a) Radiator Hose (Return)
* 82CS+83CS+84?? N901666.01 32x4x650mm (25.5”) to small diameter (metal 1.25”) pipe.
* late CS+KY+JX 251-121-082 to large diameter (plastic 1.5”) pipe.
DIY: 1.25” heater hose.

Diesel VW Vanagon T3 Coolant Hoses – Part Two – Radiator Hoses

March 9, 2010

Click to Enlarge.

Not surprisingly, the 1982 Diesel Vanagons have a unique radiator, as 1982 gas Vanagons were still aircooled.  Starting in 1983, a new style radiator was used for both gas and diesel models.

The ’82s and ’83s share the smaller (1.25”) diameter metal coolant pipes, while later gas Vanagons moved to larger (1.5”) diameter plastic coolant pipes.

Note that 1982 models also have an additonal metal feed pipe leading from the long underbody coolant pipes to the top of the radiator, while the later radiator style uses a rubber hose for the feed from the underbody pipes.

See Part One – Diesel VW Vanagon T3 Coolant Hoses – Engine Compartment – for details on how to read the information below:

(Radiator)
NLA 82 CS 068-121-253A (shown on right)
* 83CS+Later 068-121-253E (shown on left)

(8a) Radiator Feed Hose from Pipe. (note ’82 uses NLA (8) metal pipe)
* 83CS+84?? 251-121-083G from smaller (metal 1.25”) pipe.
* late CS 251-121-083H from larger (plastic 1.5”) pipe.

(9) Radiator (Feed) from Front Feed Pipe and from Underbody (smaller metal 1.25”) Pipe. (82 only)
* 82 N900785.02 32x4x70mm (2.75″ – need two for the ends of (8) front metal radiator feed pipe)
82 DIY: 1.25” heater hose.

(10-10a) Radiator Hose (Return)
* 82CS+83CS+84?? N901666.01 32x4x650mm (25.5”) to smaller (metal 1.25”) pipe.
* late CS+KY+JX 251-121-082 to larger (plastic 1.5”) pipe.
82-83 DIY: 1.25” heater hose.

Previous: Diesel VW Vanagon T3 Coolant Hoses – Part One – Engine Compartment

Next: Diesel VW Vanagon T3 Coolant Hoses – Part Three – Heater Hoses

2 Diesel Vanagons have a unique radiator, as gas Vanagons were still aircooled.  The next year, everyone go the same radiator, gas or diesel.  '82s also have a metal additonal metal feed pipe leading to the top of the radiator from the long underbody coolant pipes.  '83s also share the smaller (1.25”) diameter metal coolant pipes, while later gas Vanagons moved to larger (1.5”) diameter plastic coolant pipes.

(Radiator)
NLA 82 CS 068-121-253A  (CS >>24-C-175 000)
* 83CS+Later 068-121-253E (CS 24-D-000 001>>)

(8a) Radiator Feed Hose from Pipe. (not 82)
* 83CS+84?? 251-121-083G from small diameter (metal 1.25”) pipe.
* late CS 251-121-083H from large diameter (plastic 1.5”) pipe.

(9) Radiator (Feed) from Front Pipe & to Front Pipe from Rear (small diameter metal 1.25”) Feed Pipe. (82 only)
* 82 N900785.02  32x4x70mm (2.75" – need two - 82s have an additional front metal pipe for the radiator feed)
DIY: 1.25” heater hose.

(10-10a) Radiator Hose (Return)
* 82CS+83CS+84?? N901666.01 32x4x650mm (25.5”) to small diameter (metal 1.25”) pipe.
* late CS+KY+JX 251-121-082 to large diameter (plastic 1.5”) pipe.
DIY: 1.25” heater hose.

Fatty Acid Profiles of Biodiesel Feedstock Fats and Oils

March 5, 2010
Click to Enlarge

Click to Enlarge.

The Renewable Energy Group has released a free Feedstock and Biodiesel Characteristics Report, a fairly comprehensive analysis of – yep, you guessed it! – a whole bunch of animal fats and vegetable oils.

One area they analyzed was the fatty acid profiles of common fats and oils used as biodiesel feedstocks.

If you don’t know already, fatty acid chains are the long skinny carbon chains dangling from the alcohol on a fat or plant oil molecule.  In naturally occurring oils the alcohol is glycerol, and holds onto three fatty acid chains.  In biodiesel the glycerol has usually been replaced with a methanol, and connects to a single fatty acid chain.

(Note: most biodiesel brewers will have heard of free fatty acids, or FFAs.  These are fatty acids that are no longer attached to their alcohol.)

As a reference point, the cetane molecule in diesel is 16 cabons long, and is fully saturated (coated, for lack of a better word) with hydrogen.  (Of course the fossilized diesel fuel lacks the alcohol on the end.)

Okay, how to read this chart:

The first number shows how many carbons long the fatty acid is, and the second number tells how many hydrogens it’s missing (in these places the carbon double bonds to itself and the oil is considered unsaturated).  If you look, most of these natural fats and oils are 16-18 carbons long, very similar to diesel!

You can guess cold weather flow properties by how unsaturated an oil is.  Straight fully-hydrogenated chains pack together tightly, like uncooked spaghetti, and usually make a butter-like solid.  Unsaturated chains (missing some hydrogens) have kinks and bends where the carbon double bonds to itself, making a tangly mess like cooked spaghetti.  These unsaturated oils tend to flow better at cold temperatures (note: “hydrogenated” oils are unsaturated ones that have been treated to become saturated.)

Although unsaturated oils flow better, they also have slightly less power (less dense), and are less stable.  Those double bonds are more susceptible to degradation by oxidation, breaking apart and/or reconnecting into a varnish.

Veg On!