Chescold fridge odour

I have an older style Chescold, with the metal case and I have done all the mods suggested on this forum (thanks Adam and co) it works fantastically. On 240v I have to turn the thermostat right down or everything freezes. Even 12 volt is fantastic - but there is an odour problem. I have not smelt it when it was in the pergola on 240 or gas, but when in the car... I had to turn it off. The odour may have been there while running in the pergola but the open area may have dispersed the smell.

I repacked new insulation around the heat exchanger. I spoke with a fellow south of Brisbane who repairs Chescolds and he said he used ordinary roof insulation. I had some pink batts so I used that. I tested it for fire etc before putting it in. It is not burning. I've run it on 240 for 3 weeks, on gas for a week, but when I went for a long drive to test it on 12 v the fumes were too much. The smell is strongest at the top of the flu, but may not be coming from the flu pipe, but the general area.

Has any one else repacked the heat exchange insulation? If so what insulation was used? Is it the Pink Batts that are the problem and is there a chemical in these?

Thanks,
Black Jack