Strange FBH behaviour

Unclefista · 3rd December 2011, 22:48

When I bought my car a few months ago I found the FBH and researched it a bit on here.
I tested it according to the instructions from French Mike (thanks Mike) but supplying 12v to the proper pin or earthing it didn't do anything, absolutely dead. A few weeks ago when the temperature dropped well below 5 degrees it was still dead.
I steeled myself for a cold winter..

Today, after changing my starter, again (a long story in itself, nowhere near the end yet) I went to set off to drive the 5 miles home from my brothers and there was a new noise from under the bonnet, after getting home I checked under the bonnet and the FBH was whirring away with the exhaust very hot, yay

It seems to be working fine, it starts when I start the engine, when I stop after a short trip (not long enough for the engine to get up to temperature) it shuts down after a minute or so, result

The only worry I have is, it's been working when the exterior temp display on the dash has been between 6 and 6.5 degrees, from what I read it shouldn't work above 5 degrees ?

Does it use the car's inbuilt temperature sensor or does the FBH use it's own, and therefore might be calibrated slightly lower than the "real" reading ?

Also to confuse matters, my FBH doesn't seem to be mentioned anywhere, it's a 66232"B" not "C", does anyone know if there's any difference between B and C models ?

Many thanks in advance all

HarryM1BYT · 3rd December 2011, 23:14

Quote:

Originally Posted by Unclefista

Does it use the car's inbuilt temperature sensor or does the FBH use it's own, and therefore might be calibrated slightly lower than the "real" reading ?

Also to confuse matters, my FBH doesn't seem to be mentioned anywhere, it's a 66232"B" not "C", does anyone know if there's any difference between B and C models ?

Many thanks in advance all

They use a separate sensor, which is actually a thermal switch and I would not expect it to be too accurate.

Looking at your photo, the green paint marks are typical of what a scrap yard might put on a part they sell, so your FBH may have been one an owner fitted. As such, it may not have been one normally fitted to a 75, hence the number not matching.

Unclefista · 3rd December 2011, 23:22

Thanks Harry, makes sense

Good spot on the green markings, even if I'd noticed them I probably wouldn't have put 2 and 2 together and thought of scrapyard ID marks.
The 66232B has only a single entry on a google search, and it's an old for-sale advert, in German, so not exactly the most popular Webasto model..

Weird how it just started up today after not even a peep before, must've been disturbed by disconnecting the battery, although I've done that 4-5 times since I bought the car.

Cheers

BigRuss · 3rd December 2011, 23:48

Don't worry about it operating at 6.5 degrees the temp sensors are not that accurate

Mine works at approx that temperature, from your discription it seems to be working normally

Russ

Singvogel · 4th December 2011, 07:17

I agree - your fbh is behaving like many others so that is normal.

It's correct that they have their own temp sensor.

I know the manual says 5C but no-one seems to have told my fbh that.

Enjoy. :xmas-smiley-004:

Unclefista · 4th December 2011, 09:31

Thanks all, consider my mind put at ease

Unclefista · 4th December 2011, 18:04

Bad form to reply to your own posts, but.
I tested my coolant temps today from cold with the FBH running today and coolant was at 80 degrees is under 4 miles, a drastic improvement

Astraeus · 4th December 2011, 21:47

Hi

We use these things in our yachts, my one being an Eberspacher. Few things that can make these things problematic, They have many safety features and one of these is low voltage. There is quite a power draw when they light the glow plug. If your battery is down a bit the current drops the voltage down to 10 volts and it will not fire. Second most obvious thing can be coking in chamber. Best way to sort this is to run it on paraffin for a while. (obviously not the car)
How ever if it is working now best to leave it but if problematic again check these things

Chris

e668ecp · 20th December 2013, 14:31

I know have that exact unit on my ZTT and its not doing anything. Any suggestions?

HarryM1BYT · 20th December 2013, 15:16

Quote:

Originally Posted by e668ecp

I know have that exact unit on my ZTT and its not doing anything. Any suggestions?

Have you tried my How To below?

Might be worth trying the manual method of running the FBH, just to see if it might be the +5C stat which isn't working as it should.

3rd December 2011, 22:48	#1
Unclefista Posted a thing or two Rover 75 CDT Join Date: Sep 2011 Location: Bradford Posts: 1,478 Thanks: 1 Thanked 14 Times in 8 Posts	Strange FBH behaviour When I bought my car a few months ago I found the FBH and researched it a bit on here. I tested it according to the instructions from French Mike (thanks Mike) but supplying 12v to the proper pin or earthing it didn't do anything, absolutely dead. A few weeks ago when the temperature dropped well below 5 degrees it was still dead. I steeled myself for a cold winter.. Today, after changing my starter, again (a long story in itself, nowhere near the end yet) I went to set off to drive the 5 miles home from my brothers and there was a new noise from under the bonnet, after getting home I checked under the bonnet and the FBH was whirring away with the exhaust very hot, yay It seems to be working fine, it starts when I start the engine, when I stop after a short trip (not long enough for the engine to get up to temperature) it shuts down after a minute or so, result The only worry I have is, it's been working when the exterior temp display on the dash has been between 6 and 6.5 degrees, from what I read it shouldn't work above 5 degrees ? Does it use the car's inbuilt temperature sensor or does the FBH use it's own, and therefore might be calibrated slightly lower than the "real" reading ? Also to confuse matters, my FBH doesn't seem to be mentioned anywhere, it's a 66232"B" not "C", does anyone know if there's any difference between B and C models ? Many thanks in advance all __________________ Love is like a snowmobile, speeding across the frozen tundra. Which suddenly flips, pinning you underneath. At night the ice-weasels come... http://farm6.staticflickr.com/5331/6...77671f80_n.jpg

3rd December 2011, 23:22	#3
Unclefista Posted a thing or two Rover 75 CDT Join Date: Sep 2011 Location: Bradford Posts: 1,478 Thanks: 1 Thanked 14 Times in 8 Posts	Thanks Harry, makes sense Good spot on the green markings, even if I'd noticed them I probably wouldn't have put 2 and 2 together and thought of scrapyard ID marks. The 66232B has only a single entry on a google search, and it's an old for-sale advert, in German, so not exactly the most popular Webasto model.. Weird how it just started up today after not even a peep before, must've been disturbed by disconnecting the battery, although I've done that 4-5 times since I bought the car. Cheers __________________ Love is like a snowmobile, speeding across the frozen tundra. Which suddenly flips, pinning you underneath. At night the ice-weasels come... http://farm6.staticflickr.com/5331/6...77671f80_n.jpg

3rd December 2011, 23:48	#4
BigRuss Premium Trader 75 CDT Tourer,2.5 Launch Saloon, Omipro MG/Rover (T4) Join Date: Jul 2007 Location: Liversedge, West Yorkshire Posts: 5,418 Thanks: 1,105 Thanked 1,340 Times in 661 Posts	Don't worry about it operating at 6.5 degrees the temp sensors are not that accurate Mine works at approx that temperature, from your discription it seems to be working normally Russ __________________ Replacement Key Service http://https://the75andztclub.co.uk/...d.php?t=244732 Full T4 Testbook diagnostics available. Diesel ECU repair and replacement. Options enabled or disabled as required. Diesel X-Power 135 and "160", Rover 1.8T 150 to 160 MG 160 V6 to 177 upgrades available P.M. for details.

4th December 2011, 09:31	#6
Unclefista Posted a thing or two Rover 75 CDT Join Date: Sep 2011 Location: Bradford Posts: 1,478 Thanks: 1 Thanked 14 Times in 8 Posts	Thanks all, consider my mind put at ease __________________ Love is like a snowmobile, speeding across the frozen tundra. Which suddenly flips, pinning you underneath. At night the ice-weasels come... http://farm6.staticflickr.com/5331/6...77671f80_n.jpg

4th December 2011, 18:04	#7
Unclefista Posted a thing or two Rover 75 CDT Join Date: Sep 2011 Location: Bradford Posts: 1,478 Thanks: 1 Thanked 14 Times in 8 Posts	Bad form to reply to your own posts, but. I tested my coolant temps today from cold with the FBH running today and coolant was at 80 degrees is under 4 miles, a drastic improvement __________________ Love is like a snowmobile, speeding across the frozen tundra. Which suddenly flips, pinning you underneath. At night the ice-weasels come... http://farm6.staticflickr.com/5331/6...77671f80_n.jpg

4th December 2011, 07:17	#5
Singvogel Gets stuck in 75 CDT, 1966 2000TC P6, TD4-M47 Join Date: Oct 2011 Location: Deepest darkest Aberdeenshire Posts: 626 Thanks: 0 Thanked 3 Times in 3 Posts	I agree - your fbh is behaving like many others so that is normal. It's correct that they have their own temp sensor. I know the manual says 5C but no-one seems to have told my fbh that. Enjoy. :xmas-smiley-004:

4th December 2011, 21:47	#8
Astraeus Regional Secretary North Scotland MG ZS Exclusive 1.0T Auto 2022 Join Date: Feb 2008 Location: Tayport Posts: 5,754 Thanks: 1,676 Thanked 1,855 Times in 1,058 Posts	Heaters Hi We use these things in our yachts, my one being an Eberspacher. Few things that can make these things problematic, They have many safety features and one of these is low voltage. There is quite a power draw when they light the glow plug. If your battery is down a bit the current drops the voltage down to 10 volts and it will not fire. Second most obvious thing can be coking in chamber. Best way to sort this is to run it on paraffin for a while. (obviously not the car) How ever if it is working now best to leave it but if problematic again check these things Chris

20th December 2013, 14:31	#9
e668ecp I really should get out more....... Range Rover Evoque and ZT V8 SE Join Date: Feb 2007 Location: Yorkshire Posts: 2,232 Thanks: 20 Thanked 37 Times in 34 Posts	I know have that exact unit on my ZTT and its not doing anything. Any suggestions?