Eberspacher internal cleanup

[ianc1200]

I have an aprox 15 year old D3 (believe D3LC). It has the 401 timer/control unit. It now runs for about 4 minutes and switches off. The unit hasn't really been used in last few years (& not at all for two years) but when last really used would only then run for 20 - 30 minutes and then switch off.

I've spent the weekend reading the various threads, Eberspacher's FAQs, and have removed and cleaned the small gauze fuel filter at the pump, cleaned up the electrics, eliminated any issues of ducting being crushed, & cleaned the glow plug. The unit has only ever been run on red diesel.

The glow pug did have some gritty dirt on it. I'm wondering now whether to get the unit off to see if the combustion chamber needs cleaning, once the unit is out of the boat how easy is this?

Secondly the only other potential problem (I think) I have eliminated is the thermostat, I think I should unplug it & see if it then runs longer, or unplug and short the connections, would this be correct?

IanC

 

[alan17]

Cannot give info re stat but mine behaved in a similar manner. The fault with mine was the air intake pipe which had been formed into a "U" presumably to prevent water ingress. Problem was that water had collected in the "U" and either completely or partially restricted the air flow.

 

[Pye_End]

Have you eliminated voltage as an issue?

Mine, soon after new (only about 3 years old), used to cut out after 14 min. Turned out to be the main control board.

4 min though sounds like it is not firing up at all - is the air getting at all hot?

 

[ianc1200]

I haven't checked the combustion air intake, except to notice it doesn't drag in a lot of air like the fresh air vent. Obviously ought to have a look at this.
The voltage is 12.6/12.7 (yesterday), on Saturday doing with engine running to eliminate low voltage.
Noticed the posts about main control unit made by a couple of people who service/repair Eberspachers, they noted the high incidence of control units, but thought this referred to later Airtronic models.
When it works for 4/5mins, it works well. The typical Eberspacher exhaust noise & heater through exhaust fitting, the warm air pumped out is very hot & with great force.

IanC

 

[Grumpybear]

I went through all these checks when ours stopped working after about 6 years regular use, but eventually bit the bullet and stripped it down; the heat exchanger was badly coked up and essentially blocked. I needed a service kit (gaskets, glowplg etc) which cost about £75, but the job took about an hour once I had the unit out of the boat.

One tip - don't use a solvent to shift the fuel-soaked carbonaceous crud out of the passages of the heat exchanger - when I started the unit up the marina disappeared under a huge cloud of smoke and neighbours ducked for cover at what sounded like a burst from an AK47. The unit worked fine!

 

[ianc1200]

Thanks for that; what would you recommend if not a solvent to shift it?

regards

IanC

 

[Grumpybear]

a plastic picnic knife and lots of gentle patience