TheSamba.com :: View topic - BN4 Eberspacher Restoration and installation - 72-78

Thu Jun 10, 2021 7:11 pm

Sweet Score 8) 8)

Sun Jun 13, 2021 7:48 pm

so you posted this simply to make us jealous? :evil:

sheesh take a joke :wink:

where does the exhaust exit on a bus? the side panel?

Sat Jul 17, 2021 5:49 am

Chickensoup wrote: so you posted this simply to make us jealous? :evil:

sheesh take a joke :wink:

where does the exhaust exit on a bus? the side panel?
Yes :lol:

The exhaust exits out under the rear corner of the bus through the battery tray.

So with the price for OG metering pumps getting crazy for ones that may not even work, I was thinking about alternatives. I looked on EBay and saw they had new metering pumps for Eberspacher diesel heaters and was wonder if maybe one of these would work https://www.ebay.com/itm/US-22451901-12V-Fuel-Mete...632-2357-0

Sat Jul 17, 2021 6:37 am

Put a side door in to access it, and a battery door for symmetry.

Sat Jul 17, 2021 8:23 am

Ceckert64 wrote: So with the price for OG metering pumps getting crazy for ones that may not even work, I was thinking about alternatives. I looked on EBay and saw they had new metering pumps for Eberspacher diesel heaters and was wonder if maybe one of these would work https://www.ebay.com/itm/US-22451901-12V-Fuel-Mete...632-2357-0
Depends if it can be adjusted enough to produce the required volume, it's cheap enough to gamble on to find out.

Sat Jul 17, 2021 8:27 am

busdaddy wrote: Ceckert64 wrote: So with the price for OG metering pumps getting crazy for ones that may not even work, I was thinking about alternatives. I looked on EBay and saw they had new metering pumps for Eberspacher diesel heaters and was wonder if maybe one of these would work https://www.ebay.com/itm/US-22451901-12V-Fuel-Mete...632-2357-0
Depends if it can be adjusted enough to produce the required volume, it's cheap enough to gamble on to find out.

That's if they are even adjustable at all. Lots are pre set from the factory now. No adjustment.

Sat Apr 16, 2022 10:11 am

Not for a bus, but a later BN4 for sure. This one is set up for a thing. I need to fire it up and put the inspection stickers on. 8)

Wed Mar 22, 2023 9:59 am

Hello all

I have an old style BN4 in my '71 westy. It is the style that has the exhaust exiting through the apron around the engine, not through the battery tray.

First question is would the recirc snorkel from a later bus fit?

Second question is what should the hi/lo (stop/start) temps be at the vent opening inside the bus? I feel like it is shutting off too early and cooling off too much before it fires up again. I'm not looking forward to having to get at the temp switch to adjust it. The bowden cable is pulled out as far as it will go.

Third question is for Notchboy. Got any of those sweet stickers left?

Collin

Wed Mar 22, 2023 10:22 am

clhiller wrote: Hello all

I have an old style BN4 in my '71 westy. It is the style that has the exhaust exiting through the apron around the engine, not through the battery tray.

First question is would the recirc snorkel from a later bus fit?

Second question is what should the hi/lo (stop/start) temps be at the vent opening inside the bus? I feel like it is shutting off too early and cooling off too much before it fires up again. I'm not looking forward to having to get at the temp switch to adjust it. The bowden cable is pulled out as far as it will go.

Third question is for Notchboy. Got any of those sweet stickers left?

Collin

I'm actually not sure of the up to 71 bays and the snorkel. I know the later bays have a stamped section in the wall for the screen and capture sleeve. I would think its doable on the earlies. But a recirculation tube for the most part, in my opinion is not really needed.

I never did a real "range" test for the temp on the thermostat spring. I have an NOS one, but never installed it and did that range test. Do you have a thermostat? If so and you want more out of it then you will need to adjust.

Which sticker? The inspection one or one of the polar bear ones or the tropical one?

:lol:

Wed Mar 22, 2023 10:34 am

Since the recirc snorkel came on later models I don't think it'll be a direct fit to the earlier version, the later heater is tilted slightly more to the left to clear the dual carbs, you can likely adapt it, but it may require some trimming or extension.

Duct thermostat range can be adjusted somewhat, but it'll require digging it out of the bus for work on the bench, twist on the coil is adjusted by turning the center post, on/off can likely be altered by moving the contact points closer, it'll take some experimentation. Usually those require some fiddling with anyways, the bimetal coil changes shape all by itself over time, I suspect due to corrosion between the layers, when set up properly pulling the knob all the way out should only be needed in sub arctic temps.
An option that avoids dismantling is to install a RV thermostat inside the bus somewhere and jump the duct thermostat circuit so it never opens.

Wed Mar 22, 2023 10:48 am

Thanks for the replys.

I do have the duct thermostat, just wasn't crazy about having to disassemble so much to get at it to adjust it.

An RV thermostat is an option I thought about, just wasn't sure how long the BN4 could run before it trips the overheating switch.

I was thinking about an electronic timer to jump the duct thermostat circuit and have it automatically cycle "120 seconds on/45 seconds off" type of thing. I could adjust the timing to obtain the temps I'd like. I realize that I would have to turn off the dash switch when I'm warm enough.

I love the polar bear stickers.

Wed Mar 22, 2023 10:59 am

clhiller wrote:

I love the polar bear stickers.

Ill see whats left. 8)

Sat Jun 24, 2023 2:37 pm

Up for grabs - the rare Gray Face.

$425 - does not work, needs T3 clock to get working.

PM me if interested.

Sat Oct 21, 2023 2:04 am

Hello guys. I'm Stefano and I'm from Italy.
I'm going to install an old D1L Eberspacher heater on my 1975 double cab.
My doubt is about the intake system: I would not to drill the base sheet under the heater and I would try to bring the intake line as in the photo.....do you think it could work or putting the curve immediately after the intake hole could give problems?
Another question......bringing the intake in the tank area could work or the air in that zone is not clean?
I hope I've written clearly.....

Sat Oct 21, 2023 8:24 am

As long as the elbow's aren't restrictive I don't see why it wouldn't work, why not carry on a little further forward and pull air from under the rear seat inside the cabin?

Sat Oct 21, 2023 8:37 am

I would suggest you test that air setup on a bench test. I doubt it'll restrict the air flow much, it's probably fine.

Sat Oct 21, 2023 8:43 am

Thank you busdaddy.....have the intake line a length limit?

Sat Oct 21, 2023 8:50 am

Ollie W wrote: I would suggest you test that air setup on a bench test. I doubt it'll restrict the air flow much, it's probably fine.

Yes, good idea! What about the intake line length? If I'd follow busdaddy's suggest and I'll bring the intake point under the rear Seat....could the heater have malfunction?

Sat Oct 21, 2023 10:10 am

apozzo wrote: Thank you busdaddy.....have the intake line a length limit?
I don't know, I imagine if you make it as large as possible in the forward parts it shouldn't be an issue, any warnings in the heater's installation manual?
I've seen it done on BN-4's in single cabs, the pipe length is much shorter on a double cab.

Sun Oct 29, 2023 12:26 am

Here I'm with some update guys.....finally I've decided to put the heater under the bus....the engine zone in my opinion is small to put all the devices (heater, tank, pump, pipes and electric unit and relais) rationally.
So, I've decided to insert the heater in the middle of the original heating tube (the 90mm One). It will intake fresh air from the rear part of the tube and will send hot air from to the front party of the same tube.
I've created the bracket to support the heater and the wiring until the Cab for the control unit and the electric unit, relais and switch. The tank will be collocated in the engine van with another self made bracket.