VW to Napa Hose Conversion
for many '86-91 Vanagons

 

I have seen a few posts on the Vanagon Mailing List about coolant hoses for our beloved Vanagons. I have a partial list of hoses that I have used, in some cases I'm sure there are better solutions, so feel free to comment.

We have a Napa FLAPS here so these hoses are Napa part numbers where possible. Some of the solutions I use won't be acceptable to some of you so I will list the hoses that require just a trim to the correct length first then I will discuss my solution to other more complex hoses.

Using the letters and part numbers from the chart, I will state the size and shape of the hose in inches and describe them as best I can remember. I have an 86 westy, 2wd, 4 speed, and A/C.

 

Coolant Hoses - Wasserboxer 86-91 2WD

 

Hose:

 VW Part #: Napa Part #: Description: Dimensions:
H 252-121-130b 7990 Right head front to valve.  1" ID, 6" long. Has 2 60 degree bends
J 025-121-058e 10050 Thermostat housing to oil cooler pipe .472" ID one end, other end .635", 3" long
R 025-121-058h 9807 Expansion tank to pipe tee .620" ID both ends. 90 degree bend each leg 4.5" long
? 025-121-073H 777 Thermostat housing to water pump pipe. This hose doesn't  seem to be listed on the chart. Good picture of it in Bentley on 19.11. It is the big one there with the 90 degree turn. 1.5" both ends 90 degree bend 1 leg 6" other 4"
O N901287.03 1" hose* Water pump feed to right side of crankcase. 1" ID 3" long
D N902873.03 1.5" hose* Valve to radiator feed.  

F

 251-121-058a 1" hose* Thermostat housing to valve. 1" ID about 2ft long
G 443-121-107A

 

 This is a 7mm hose from a VW FLAPS, Napa here doesn't carry 7mm hose  

K

 025-121-058D

 

 Oil cooler to oil cooler pipe from from thermostat housing. No direct solution here. However 5/8" heater hose about 2 feet long can be run directly from the oil cooler to the thermostat housing eliminating the need for hoses J and K. I like the one hose solution better than the normal path as there is more clearance from the oil cooler hose and the header pipe. My hose K got brittle and blew coolant all over my clean engine.  

L

 025-121-058G

 

 Oil cooler to oil cooler pipe from water pump. No Napa hose replacement and no good way to eliminate this hose that I have found. Maybe someone else can find a sub.  

M

 025-121-058J 3/8" ID hose A straight hose will function fine here 3/8" ID 4" long

P

 443-121-107A

 

 7mm VW FLAPS. Right head to pipe  

Q

 025-121-108D

 

 No Napa solution. Pipe at water pump to expansion tank. This hose is designed to take a lot of flexing between the engine and the expansion tank. I need help on this one, somewhere there must be another application that uses a similar hose. 1" ID one end, 3/4" ID other end
S 025-121-058B

 

 No Napa solution. Thermostat housing to pipe tee. Need help on this one also. 1/2" ID one end 7mm other end, about 14" long.

* I got a 3ft long heavy duty Napa hose and cut it to fit


Heater hoses are all 5/8 inch hose and no real big problems here. I replaced the Tees for the rear heater with 5/8" diameter Tees on all three points because  the originals had 2 5/8 and one 1/2" point. 30 feet of 5/8 hose is needed to replace all heater hoses. Straight hoses will even make the turns for the front heater under the dash without too much problem. However if your inside front heater hoses are good I would consider keeping them as they require a bit of time to replace. I was considering connecting my heaters in series instead of parallel, but backed off because I thought it might degrade the heat. Napa has regular grade or premium grade heater hose and so do many other FLAPS.

For the rest of the hoses I used copper pipe, 90 degree elbows and various copper pipe adapters. This requires soldering some pretty heavy pipe but could be done with a plain propane torch. I bought  Napa heavy duty hoses that are used mostly on diesel trucks and industrial applications. This was a mistake I would go with regular grade  hoses if I did this again.  The heavy duty hoses has double layers of nylon reinforcement and outside wrapped with nylon. It is a real pain to work with  and after a couple of days working with them I discovered why most Illinois diesel mechanics appear to be fresh off the Minnesota and Wisconsin farms. I used  6 feet of 1.5" ID hose, 3  feet of 1.25" ID hose, 3 feet of 1" ID hose. Most 1" stuff was used on hose above at item F and O.

 

Hose: VW Part #: Napa Part #: Description: Dimensions:
A 251-121-082 1.5" and 1.25"  hose Upper Rad feed hose Radiator connection is 1.33" and long hoses are 1.5", straight 28" long. I used some 1.25" hose at the radiator end and made an adapter using 1.25" copper pipe, adapter to 1.5" copper some 1.5" copper pipe then 1.5" hose to the long feeder hose.
B 251-121-083H 1.5" and 1.25" hoses Lower radiator return hose Same ID on hose as A above however 3 90 degree elbows are  required on this one. Use a short 1.25" hose, a  short 1.25" pipe, 90 degree elbow toward the rear a short 1.25" pipe (make this pipe just long enough to get aft of the radiator and radiator holder bracket), 90 degree elbow pointing up and slightly to the left, enough 1.25 pipe to get up high enough to get over the spare tire, a 1.25 90 degree elbow pointing toward the rear, some 1.25" pipe, an adapter to 1.5", some 1.5" pipe then 1.5" hose to the radiator return long pipe.
E 025-121-062E 1.5" hose and  some 1.5" copper pipe Return to thermostat housing 1.5" both ends however this one goes up and over the transaxil. Use a short 1.5" ID hose about a 2.5 inches of copper 90 degree up, about 10 inches (check this measurement) 1.5 " ID copper pipe up line these up so your copper pipe rests nicely in the hose holder above the transaxil), Now 90 degree copper elbow and you are heading over the transaxil, install enough 1.5" copper pipe so you line up with the thermostat housing. (hint it is best to be a little too long with the pipe going over the transaxil or  your hose might cause shifting problems). Now turn 90 degrees with copper elbow toward the thermostat housing install a short 1.5 in ID pipe in the elbow. use a 1.5"ID hose to connect to the thermostat housing. That sounds pretty involved, try this for directions from the long return hose go back a few inches up about 10 inches over the transaxil about 20 inches and turn back toward the thermostat. What you end up with is a copper pipe with 3 90 degree elbows attached.
N 025-121-058M 1" hose, home made adapter  and some 7mm hose Left head to pipe One end is 1" other is 7mm. Start with a short 1" hose, use a very short 1" ID copper pipe, 90 degree copper elbow, I then used an adapter from  my local hardware store from 1" down to 1/4" ID copper pipe  that I used and then just stuffed the 7mm hose over that. The original hose on my 86 had sprung a leak and for a while I thought I had a head leak.


If you have any questions or suggestions please drop me a note.  I have no interest in Napa and used them for my convenience only. They allowed me to take a box of hoses into their store in Carbondale, Illinois and compare VW hoses with their stock.



Darrell Boehler
Makanda Illinois