Exhaust fumes in cab

[roosmith]

When running on veg oil we suffer with fumes in the cab (only noticeable when idling only). I don't know if it is just worse when on veg oil or it is something inherent with veg oil. Doing various searches I've seen talk of the EGR being blanked off in the same sentence as fumes, which would fit with exhaust fumes at idle.

Should I be looking at blanking it off? Is this a good mod to do?

[g8dhe]

Are you sure it isn't just exhaust fumes being blown back under the chassis and then pulled in to the Air Con path ? This is typical on a V6 when the cam seals leak and drop oil on the exhaust - when travelling no problem, stop at lights and a slight breeze blowing from rear to front and the fumes get sucked in by the air con intake!

[Northern Bongolow]

regardless of the fumes blanking off the egr is a good idea, blanking off the egr gives the engine cleaner cooler air to burn so it improves the bang in the cylinders, not as kind to the planet though as your putting out unburnt fuel and soot particles etc. and the better bang makes the engine run slightly hotter, not by a lot as i could not measure any increase but internal temps must rise.
it also stops putting soot etc into the inlet side of the engine so it should run better when its clean.

[roosmith]

Thanks for the replies. Agreed Geoff, it did cross my mind that was a possible cause. One mod I was planning on was having an override switch for the fan, so air being blown backwards might help with that. Thanks for the explanation Northern on the EGR. The Bongo isn't exactly a Prius is it, so a little more soot and emissions ain't going to make that much difference. It's like the new Porsches with stop start - what's the point!

[Northern Bongolow]

just got a new 510 hos truck, 14 ltr jobby, when the cruise control is on and it goes down hill it drops down to tick over . bit unnerving at 44 tns. i think they are ringing the cloth out a bit much myself.