Espar delayed combustion?

[SprintED]

Wondering if anyone has experienced this with their espar:

Started my 05 158" the other day in about 30 F weather with the Aux heat button on, which usually results in the espar starting up shortly after start up (a minute or so). Engine is running with no jet sound yet when I hear a boom sounding similar to the sound made by gas soaked logs of a campfire as they are ignited by a match.

Go to the front of van...jet sound is starting and there is the smell of unburned and burned diesel fuel, not the usual diesel exhaust sort of smell.
Pretty sure there was some sort of delayed combustion in the espar that resulted in either a delayed spark or excess fuel entering the espar prior to ignition. The Espar operated as per normal after the mini explosion and has not done it again in 10 - 12 uses of the Espar since

Any ideas on what part of the Aux heater/7 day timer/Espar system may be acting up or responsible?

Thanks

Ed

[nocky]

The smell of diesel is normal because it does not have a cat to run through. If mine has sat for awhile it will make that pop noise too. I think the manual said to run it once in awhile like you would an A/C unit.

[Petey]

Hello,

My first post... I have a 2005 140 Cargo with the auxilary heater and timer. A couple of weeks ago my heater was on (while the engine was running) and it began to smoke and smell terrible. I have since run the heater with the engine off as well and it exhibits the same symptoms. I emailed espar yesterday and the replied today and said I should probably change the fuel atomizing screen. I guess I'll give that a try.

[SprintED]

Nocky,

My espar is running almost every day of the winter and rarely is idle for more than a day or so. Also the smell I refered to (diesel fuel odor mixed with diesel exhaust odor) was not the usual smell (100% diesel exhaust odor) that eminates fromt he espar when it is doing its thing.

The boom in question did not occur after a period of espar inactivity.


Did your "boom" occur using the Aux heat (keep engine temp up while idleing) setting or on the timer (preheat a non running engine) setting?

Thanks

Ed

[Therberg]

I had the same problem in March 05 with my aux heater. It would smoke a lot on start up then shut down .I called the techs at Espar and they suggested that the unit may need cleaning ,that the combustion chamber and glow plug get fouled with carbon and soot.

The aux heater is fairly easy to remove from van and disassemble. Once apart there was a considerable amount of a very fine black soot in the combustion chamber (approx 5 tablespoons ) I used a brass brush to loosen soot from all the fins and air /fuel induction nozzle. Then reassembled the unit using new gaskets ( part # 05133307AB).

The aux heater seemed to work normally for two weeks then started doing the same thing. I decided to take it to the dealer. The Sprinter Tech plugged the DRB III scan tool in and it showed only that the heater had several no start flame outs, the scan tool did not show any faults with any internal parts of the heater. He called the tech support line and they said to just replace the unit.

The new unit came in within a week , returned to the dealer to have the "defective " unit swapped out. The same thing happened , the heater would just smoke a lot and not fire up completely. On one of the start up attempts Bob the sprinter tech noticed that not much air was coming out of the little muffler , he decided to take the muffler off and to both of our surprises the heater fired right up. The muffler was almost completely clogged with soot and the corrugated exhaust pipe as soon as he flexed it broke in two, it was corroded from salt spray from the front wheel. He tapped the muffler on the shop floor and was amazed how much soot and rust came out. They ordered the muffler and it came in within one week.

All in all 3 trips to the dealer , Fleet Maintenance a Freightliner dealer in West Seneca NY. near Buffalo, I never had to wait more that an hour. Problem solved for know, I believe that this is going to be an ongoing maintenance item. The tech I talked to initially at Espar said depending on usage that the aux heater should be cleaned yearly much like an oil burning house furnace. I also believe that the little muffler will not last longer than 2-3 years.



Tim H.