Now traditionally with air called Volkswagens if you want some heat in the cab you have to rely on air being blown from the fan of the engine over the exhaust system inside some heat exchanges that’s where it got warmed up and then it got blown through the heater channels in the bodywork into the cab but because of the pared down design of the thing it doesn’t have any of that our VW has an auxilary petrol run heater under the bonnet it doesn’t work why now the controls of this heater may seem a little unusual the first one is almost exactly like an egg timer sir clockwork device that you can wind up gives you up to 20 minutes of run time now the other control is this one down here this is for the heater temperature is currently in its cold position so the further you pull this out the hotter the heater will go you just pull it out which I can’t do then you can actually control the amount of heat so the further out it is the hotter it’s supposed to be but at the moment that’s going nowhere then of course as you can hear even though the clock works on is on position the heater isn’t actually working either so clearly is a couple of issues that need further investigation I remove the cover of the thermostat in the hope of finding the cause of the jammed cable so what we seem to have here is some kind of thermostatic switch you can see is actually in the duct here that takes the hot air into the cab so this little spring thing will be some kind of bimetallic strip well Bowden cable here that was jammed goes to this lever here and that should looks a bit move so depending on what happens to that strip when it heats up whether it coils up or uncoils on the end of that shaft you’ve got this little D shaped cam I’m looking at it doesn’t seem to be working but that supposed to presume we’re go to all the time your little egg timer is running but actually turns on the fan which also sounds like it needs to be balanced perhaps but this is clearly seized this needs an adjustment as well so this isn’t working you can’t adjust the heat temperature so therefore I need to change this one it’s very difficult to track down rare parts like this but after a long search when I find a replacement unit in Germany for a hundred bucks or 60 quid but will it cure the fault so now while I collect our wires this should now go on so just to show that works it’s gonna turn on Peter warm up the bar metallic strip you see actually shrinks slightly it’s because it now thinks it’s up to temperature but if I wanted a bit more heat in the camera then pull on a little button for the temperature control outs which moves the Bowden cable which moves its arm so this works perfectly as you’d expect so just turn out of the go so again turn it back down to the off position so this is working wonder if it’s all have to do now is pop it back into position and see if it all works properly so let’s try this one more time just turn on our heater that’s good it’s a little feel by a math check what else could be wrong because at Loman it nothing but cold the petrol in the system is vaporized and ignited by a special heated spark plug and I checked to see first it is actually a spark that lovely fat spark that’s working a treat we also notice there’s no sign of any fuel actually on the plug it’s not wet in any way at all I think probably the problem is having to do with our fuel supply there seems to be no fuel coming through the lines at all and that would explain why there is no heat the fuel pump which sends the petrol to the heater is on the bulkhead behind the driver’s side wheel I connect up some power and see whether it does anything at all let’s give it a go I can hear kind of sparking noise which means there’s definitely load inside the pump so it’s trying to do something it just happens to be seized either way it’s not doing what we needed to do so we need a replacement for another hundred dollars the supplier of the thermostatic switch also managed to find me a secondhand pump if this doesn’t solve the issue I’m running out of things to look at okay so now everything’s back in place it’s try it one more time so on goes the timer I can hear a kind of a faint thundering noise which means it’s actually burning fuel inside the chamber so the next question is if we’re getting any hot air at this end what are you going a little bit of warmth coming out of the vent here so that’s it we’ve cracked it smashing
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