Where should DPFs be mounted?
Are there any diesel engines where the regen fuel is not injected directly into the engine on the exhaust stroke? To my mind a DPF should ideally be as close as possible to the exhaust manifold and have the regen fuel injected to the DPF and not the engine cylinders, to avoid unburnt fuel finding its way past the piston rings into the sump, thinning the oil increasing the oil level and possibly initiating a self destructing overrun.
I have a Civic 1.6 diesel parts diagram that shows an integrated DPF/CAT, replacement cost £478. The integrated unit is very close to the exhaust manifold consequently should burn hot and minimise clogging.
A parts diagram of a 1.7CDTi Zafira shows the DPF is separate from the CAT and situated in the middle of the exhaust system close to ground level - a cold location that will take ages to heat up. Replacement DPF cost £1300. No contest as to the most effective system.
Placement of DPF in the exhaust system and where exactly the regen fuel is injected are vital issues given little or no prominence in reviews.
I have a Civic 1.6 diesel parts diagram that shows an integrated DPF/CAT, replacement cost £478. The integrated unit is very close to the exhaust manifold consequently should burn hot and minimise clogging.
A parts diagram of a 1.7CDTi Zafira shows the DPF is separate from the CAT and situated in the middle of the exhaust system close to ground level - a cold location that will take ages to heat up. Replacement DPF cost £1300. No contest as to the most effective system.
Placement of DPF in the exhaust system and where exactly the regen fuel is injected are vital issues given little or no prominence in reviews.
Asked on 1 March 2015 by scramble
Answered by
Honest John
That makes total sense to me. Mazda Skyactiv 1.5 and 2.2 diesels, Renault 1.6DCIs (also used in Nissans and Mercedes C-Class) and the new GM 1.6CDTi all have exhaust manifold in head engines where the turbo is bolted directly to the head with the DPF directly after. The Honda 1.6CTDI has a close coupled manifold, but it is external.
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