Smoke from roof panel heater vents

[jeffruss]

I drove about 40 miles recently and on arriving at my destination noticed a small amount of smoke coming from the two heating vents in the roof panel. There was also a smell similar to burning or smouldering paper. Didn't notice any problem with smoke from the vents in the front.
I've only ever used the front heater controls and so I'm not sure what causes hot air to come through the roof panel vents - whether it's the front controls / back controls or both.
Just wondered if anyone has any idea what might be causing this and where the source of the problem might be. [Not sure where the ducting goes behind the panels to get hot air from the heater matrix (front or rear) to these roof panel vents]
I had a similar problem on the way back after about 20 miles when the engine had really warmed up.

[haydn callow]

Back controls direct air to those vents,,,,,sounds as though you have a duff motor or somthing.....switch off AT ONCE (the rear heater) and get it sorted asap before you have a fire to contend with

[jeffruss]

Thanks for your help Haydn.
As I said, I never use the rear heater controls so the fan wasn't on and the temperature set to cold.
I'd better get it to a garage ASAP.

[teenmal]

Hi jeffruss,

It might be worthwhile checking your rear heater matrix for leaks.(Steam)

Cheers.

[g8dhe]

Just wondered if anyone has any idea what might be causing this and where the source of the problem might be. [Not sure where the ducting goes behind the panels to get hot air from the heater matrix (front or rear) to these roof panel vents

The Lush diagrams give some feeling for the run;
http://lushprojects.com/bongopartsmk2/c ... mgno=.html

[missfixit70]

Allsorts of useful links/drawings on this FAQ at the top of the forum that may help- http://www.igmaynard.co.uk/bongo/forum/ ... 43&t=28727

[Northern Bongolow]

i think this may be coincidental thats it coming out of the roof vents.
is it actually a problem behind the dash that is running through the gaps in the A post pillars and going over your headlining to the vents.
also is the self closing on the sliding door still working.

[missfixit70]

I think you may have been imbibing of a different kinda smoke Ady to come up with that theory , if there was a smoky problem behind the dash, I think it'd show up in the cab waaay before finding its way back there, & how would it find it's way out of the rear vent channels if it wasn't coming from the heater box gubbins type area ?
Could it possibly be smoke/dust of some sort being sucked in at the bottom inlet vents on the floor at the rear? There is no external inlet at the rear before anyone suggests it.

[teenmal]

I think you may have been imbibing of a different kinda smoke Ady to come up with that theory , if there was a smoky problem behind the dash, I think it'd show up in the cab waaay before finding its way back there, & how would it find it's way out of the rear vent channels if it wasn't coming from the heater box gubbins type area ?
Could it possibly be smoke/dust of some sort being sucked in at the bottom inlet vents on the floor at the rear? There is no external inlet at the rear before anyone suggests it.

It might be worthwhile checking the rear heater matrix for leaks.(Steam)

[missfixit70]

Is there an echo on this thread? Certainly worth checking (the matrix - not the echo).
Could be siezed motor, or all sorts of things, get it sorted asap though just in case, don't want a bongo fireball

Jeffruss, if you stick your location in your profile by clicking on user control panel top right of the screen, there may be local help/suggestions available.

[teenmal]

Is there an echo on this thread? Certainly worth checking (the matrix - not the echo).
Could be siezed motor, or all sorts of things, get it sorted asap though just in case, don't want a bongo fireball

Jeffruss, if you stick your location in your profile by clicking on user control panel top right of the screen, there may be local help/suggestions available.

[jeffruss]

Thanks for all the help / suggestions today. I mentioned I hadn't used the rear heating controls before so I've just tried to switch on the fan. It doesn't work. I'll need to find out why this is and also get the rear matrix checked ( as you suggest) assuming it hasn't previously been removed.
I'm beginning to think there might be a slight exhaust problem and perhaps fumes are being sucked into the rear heating system somehow.
I'll check with my local Bongo friendly garage tomorrow.
PS The sliding door adjustment mechanism is working.

[missfixit70]

Can't see how the exhaust can be getting sucked into the rear heater unless you've got bad sill corrosion (even then I'd say reasonably unlikely as the system is pretty much encased in plastic) - as I said, there's no external inlet.
I take it you switched on at the front? as it won't work independantly.

[jeffruss]

Thanks Kirsty - No I didn't realize the rear heater won't work independently. I'll try it again.

[missfixit70]

It's explained in the FAQ link I posted above (click on the blue bit)