Eberspacher B2 Rebuild Project

[64Bug]

You will recall earlier in this thread, that pictures of a support stand were posted that would make it easier to work and test the B2 heater. Since that time, some additional modifications have been made.

The changes incorporate the installation of a small gas tank with gas lines and a 12 volt termination block and switch.

A dual brake fluid reservoir from a 68-up Bug was used the gas tank. The separation wall inside the reservoir was removed so that the tank would hold more fuel and any overflow gas could be reused.

The dual outlets allow you to connect both the fuel feed and fuel overflow lines. (These fuel lines need to be made just a bit longer and better secured.)

Depending on the units operating voltage you can use a small Lawn and Garden battery or charger for the power supply.

A 3 post electrical terminal block was used for connecting the voltage supply. This minimizes any arcing and makes connections much easier. One post was used for the negative or ground. The other two posts were positive with one having solid power and the other post having a switch controlling its power. This works great for testing the individual parts, such as the fuel pump, fan etc.

Detailed photos:

Wiring Diagram:

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When you turn it on, does it return the favor?

1974 Westfalia
1964 Beetle (stock)
2017 Santa Fe

[JeffL]

I have enjoyed the tread. About 7 years ago I installed one in my 63. Not many people know much about these so I went through all of the motions described above.

Did you know there is a snorkle that goes in the circular shift tube cover? It is used to allow air under hood. Most older cars have a loose fit but the original Beetles are too tight so the snorkle was a 90 degree bend that pointed down to get air.

Some of the later units did recirculate cabin air and this eliminated the issue at the expense of another hole.

I used mine every winter for 5 years. I found out that at 6 volts, some time the voltage was not high enough at idel to get enough heat on the glow plug. Sometimes I'd have to be off idle to get the glow plug in operation.

I lucked out and didn't have to rebuild the unit. I just cleaned everything. Below is a picture of it in my restored 63 Sunroof.


Jeff

[MTIguy]

Been reading this post off and on and this is great stuff. If I have said it before I'll say it again I LOVE SAMBA. I read posts for a long time prior to signing up in fear of being an idiot. I made a contribution to SAMBA because I can't imagine the day this sit ceases to exist.

Awesome job guys. I have stock heat, never even knew this existed. I will not own one in my 66 but man, just good knowledge.
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I know who I am! I'm the dude playing the dude disguised as another dude!

[64Bug]

I'm pleased that someone actually reads this stuff and gets something out of it. It makes it all worthwhile.

You are correct, the site is incredible and everyone is always willing to share their knowledge.

JeffL..

Great job on your rebuild. Looks awesome!

[JeffL]

[my 66 bug]

Great stuff. I have been working on an 8345c made by stewart warner and am also in need of a fuel pump rebuild kit. The diaphram is old and brittle from age. The heater looks great but the exhaust pipe is rusted away.. Has anyone ever had a new stainless pipe welded to the heat exchanger?? Any and all ideas or advice would be grearly appreciated.. I have a shot of my heater in my gallery.. Dave

[64Bug]

I'm by no means a welder, but from my earlier days I recall that stainless steel is not the easiest metal to weld. I think that only a TIG welder will weld that stuff, which means unless you have one, you would need to take it to professional welding shop.

Would there be an alternative way to attach the pipe other than welding?

Short of that, you could always weld in a short length of standard exhaust pipe.

As for your fuel pump, I have had some success with using the diaphragms from a standard fuel pump from a Bug. You would need to cut it down to size though.
_________________
When you turn it on, does it return the favor?

1974 Westfalia
1964 Beetle (stock)
2017 Santa Fe

[Bruce]

[Cerot]

Great thread!
Im trying to get a B2 working in my 65 right now, when I pull on the knob, I hear it making some very quick "click click click" noises, but no heat. A guy who, like everyone, had one back in the day, mentioned that the plug might be shot?

[64Bug]

I doubt its the plug at this stage of the investigation. The quick clicking is the fuel pump not pumping fuel. First off replace all the fuel lines. Now check the the diaphragm material inside the pump. It is probably shot after all these years and will need replacing. Remove the fuel line from the jet carrier and fire up the pump. If it is working you will see gas coming out the end.

Let me know how us know how you make out
_________________
When you turn it on, does it return the favor?

1974 Westfalia
1964 Beetle (stock)
2017 Santa Fe

[my 66 bug]

Once again I find myself wondering if I really belong to the Samba or if there are just some people out there that are just so anal to questions and threads that they have to make you feel like crap!! Sorry for asking a heater question on a heater thread.. Guess its my fault for asking a couple generic questions about SW when it should have been B2.. I will stop since my input is of no relevance..Dave

[Bruce]

Dave,
Would you go into your local Ford dealer to ask them a technical question about your Chevy? The same applies here. There are a whole bunch of experts returning to this topic who know all about Eberspacher heaters. This knowledge does not apply to SW heaters because the SW heaters work very differently. Most likely, the experts who do know about SW heaters are not looking at this topic (since it has nothing to do with SW heaters).
Just start your own topic with SW in the title. How difficult is that?
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[Bruce]

[my 66 bug]

Just want to ask a couple generic questions about the eberspacher heater in this discussion. Does it opperate with a heat exchanger and if so is it stainless steal with an exhaust pipe? And is it fed with a fuel pump?? You see I am well aware of the name difference between the two heaters and can clearly see that one is a ford while the other is a chevy. That was not my question in the post. I have been watching this forum for a long time and figured that this was the first heater thread since last winter and made a comment about needing a fuel pump and asking a general question about welding stainless.. I have learned my lesson an will let the rest of you handle the technical.....Dave

[64Bug]

Dave,

All "vintage" Eberspacher gas heaters operate with a heat exchanger. Basically a combustion chamber with with a sealed outer chamber. It does have an exhaust pipe as well as a fresh air intake vent

Most of the early models have a fuel pump. Then they added a pressure regulator. Some models of the BN2 have what they call a metering pump, which is a fuel pump that automatically meters the fuel into the combustion chamber. I'm not familiar yet with the later models like the BA6 and BN4 models, so my comments are based entirely on models prior to these.

I am open to disagreement, but I believe the combustion chamber is made of stainless steel in all the Eberspacher models.

Hope this helps
_________________
When you turn it on, does it return the favor?

1974 Westfalia
1964 Beetle (stock)
2017 Santa Fe

[Cerot]

After testing, yes after about 2 seconds it starts to click once every second or so, maybe a bit longer. Gas was pumping out of the line, so the pump seems fine. The orange fan thing in the front was not spinning though, and no heat resulted. Also, the little red light inside was not turning on. Do these have some kind of internal fuse that could have blown?

[Bruce]

If the fan isn't turning, you have to figure out why. Trace the wires from the fan, is it getting voltage?
Take the fan out, sometimes the bushings the armature rides in get stiff. A little drop of very thin lubricant will fix it. Don't use thick oil, it has too much drag when it's really cold out.
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[vanover]

Hey guys I just got a B2/201246A heater and wanted to know how to test this baby. There are two wires that look like they need to be attached. Wire 1 comes from I believe to be the level switch, think this goes to positive? wire two two goes down to the bottom of the unit and appears to be a ground. How is the best way to test, its getting cold and this new toy needs to be used
Thanks

[64Bug]

Great news on the material for the Fuel Pump diaphragm.

We went to Buffalo for the Thanksgiving holiday and I persuaded my wife to make a side trip to Harbour Freight.

I picked up several sheets of tool box liner material. It is the solid kind, not the perforated stuff.

Each sheet is about 15" x 22" and is less than a 1/16" thick. It is gas and oil resistant!

I cut one out. The diameter is 1 5/8" in diameter and using a leather punch, I was able to punch out the hole for the center.

The material works great and does not curl and disintegrate. And I have enough to last several lifetimes.
_________________
When you turn it on, does it return the favor?

1974 Westfalia
1964 Beetle (stock)
2017 Santa Fe

[MortalEngine]

Bought the rebuilt 12V B2 from 64Bug a few days ago - he got me started ...!
Here is the German version of the B2 Installation Manual (published in March 1970) - it contains some vital info including the hole dimensions and placement. If I get to it I will possibly translate it at some point - but it should be usable as is. if anybody needs to know anything specific let me know.

it says the fuel intake pipe should touch the left wall of the tank to avoid interference w/ the fuel gauge float.
btw picture 11 on pg 3 mentions the air intake snorkel in place of the shift tube cover.

There is more info here - sorry it is in German

http://vwbus2.dyndns.org/bulli/michaelk/vw_bus_d/rlf_frischluft/index.htm#F5

one thing worth mentioning is section F5.3 1-3 - it says explicitly to provide an air gap in the fuel return line when bench testing. too much back pressure there will cause the heater to run rich and smoke. so a simple Tee for the return line is probably not a great idea.
Fuel consumption should be 15cc's in 225 - 200 seconds.
will post more as I read it....