FYI.Motors with Def.

I misread this wrong and was going to respond a different way but read the last quote. Yes do not disconnect the engine side batteries. When you shut down the engine the def pump will run and drain the def lines. 15 minutes might be longer then it takes but the engines have to be cycled down. Some engined drain def, some cycle the injectors to clean them, Turbos will cycle the vanes, etc.

fairway2002 wrote:
Was getting MH serviced this week. 5 out of 5 trucks getting repairs had emissions problems.

The service manage told me that MH with Def should not turn off the batteries for 15 minutes after turning key off. It does some kind of Def line cleaning. Hope this helps.

Typically turning off the batteries in a MH involves only the house batteries, not the chassis batteries.

Maybe Volkswagen could offer diesel technology advice.

mayorb wrote:
Today's diesel engines are a modern marvel with the power that they have. Unfortunately with all the emissions control that is basically muted. I just bought a new 2500hd gas. Does it have the power as diesels? Far from it. But when i see that the gas engines are rarely in the shop, this outweighs that the diesel engines. BTW if I had a MH I certainly would look at a DP.

mayor

Diesel SCR technology using DEF is a double-edged sword. Using SCR, manufacturers where able to re-tune their fuel mapping to give increased HP, Torque and fuel mileage and still reduce NOX emissions. I don't like adding DEF but, factoring the increase in power, economy and the reduction of nitrogen oxides, it's a relatively simple and trouble free system if maintained correctly.

Today's diesel engines are a modern marvel with the power that they have. Unfortunately with all the emissions control that is basically muted. I just bought a new 2500hd gas. Does it have the power as diesels? Far from it. But when i see that the gas engines are rarely in the shop, this outweighs that the diesel engines. BTW if I had a MH I certainly would look at a DP.

mayor

15 minutes may be a little extreme, but MH could be different. For 6.7L Ford pickup with DEF sucks the def back out of the line into the tank when the key is shutoff. But at most, that lasts 15 seconds or so.

More likely, the owners let them sit and idle too much plugging the DPF up to the point that they cant get a good regen. these emmision systems cannot handle extended idling. these are not like the old days, where an extended "warm-up" period are needed. the other thing is many MH's just dont get driven enough. I cant tell you how many MH's you see in the campground with hoods up, starting hard, etc. The worst thing to do to any mechanical device is to not use it.