Photographs are a mixture of overhauls of two different D1LCC heaters plus some additional photographs taken much later. This explains why the pictures have continuity errors.
The D1LC and D3LC models have much of the electronics outside the case but servicing is similar, the 24 volt model also has an additional glowpin resistor inside the case.
Disassembling the Eberspacher D1LCC heater
Click on images for better quality.
Pump, loom and controller were removed with the heater so it could be bench tested before replacing. If preferred the heater can be removed leaving these in place.
The exhaust port is very badly corroded. We have developed a method to repair this, waiting for testing before publishing.
Contact us if you need details.
This D1LCC heater had been running on the notorious pre 2011 ‘red diesel’ and it was very obvious why it had failed. We have never seen an exhaust port with more solid carbon. The dark stain is penetrating oil applied to the fixing stud nuts. Do not replace rusty nuts and locking washers with nylock nuts, the nylon can melt.
Release the hood by lifting clear of the pips and easing it away.
Remove the glowpin wiring nut, its connector is a single part. Tip:- fit the nut back onto the glowpin so it does not get lost. Press in the plug retaining latch, the plug is usually very tight and here a screwdriver was needed to help ease it out by levering on the plastic protrusions by my thumb.
Remove the plastic rivets. With solid head rivets two chisels can lever them out undamaged. Ones with a central pin can be cut off or the pin driven inside, they are usually not reusable.
Replacements are available on Ebay.
Remove the 4 crosshead screws securing the blower unit. Check the condition of the gasket, usually it can be reused.
Remove the 2 screws securing the combustion chamber cover. Ensure the screwdriver bit is in good condition and is the correct size as these screws can become very tight.
Undo the cable cover screw. It usually needs a hex key.Turn the air inlet grille in either direction and wiggle to remove it.
If it is jammed it may have to be levered off.
Remove the D1LCC case.
An Eberspacher D3LCC heater has two additional metal plates on the burner assembly (not shown).
Combustion air inlet, Fuel inlet, Exhaust outlet.
Rear side view.
This exhaust outlet is very badly corroded,
it should be same length as the inlet pipe.
Glowpin top - ECU on right.
Flame sensor left, overheat sensor middle left.
Disconnect the fan and two sensor cables from the ECU. Lift the retaining latch, arrowed, and slide out the ECU.
This glowpin hole and screen covered in very heavy deposits. These deposits were solid and would not remove easily. The manual says grip the tab with pliers to remove screen. No chance with one like this even after removing some deposits.
If the screen cannot be removed with pliers.
1 Bend the tab out of the way then drive a
2 The ring nearly broken, lever inwards to break it.
3 Prise the screen away from the sides until loose.
Cleaning the Eberspacher D1LCC
Remove the glowpin, inspect and clean.
It can burn away close to the tip, this one is OK. Also the wire may sag and short circuit to the next turn. The seal has a soft mastic type material, treat carefully.
D1LCC / D1LC and the later generation D2 / D4 glow pins. Failure of these older generation glowpin types are fairly common, usually failing open circuit.
Replacements are readily available.
The clogged D1LCC Glowpin screen.
Much of the surface carbon broke away whilst removing. We were very surprised it had kept going for so long, a D2 would have stopped long before this, the larger screen must help. New screen lower right.
D1LCC Combustion chamber cover plate removed. Part of the white felt seal has separated and is stuck to the plate.
When cleaning the combustion chamber cover plate check the air channels are not obstructed.
D1LCC Combustion chamber after cleaning. The burner and the semi-circular plate cannot be removed so unlike the D2/D4 there is no access to the channels underneath for mechanical cleaning. Chemical or ultrasonic cleaning may be required.
Check the vent from the combustion chamber to the glowpin chamber is clear, ends marked with green arrows. Check the fuel supply hole and the circular grove from it are clean, marked with yellow arrow.
Check the holes in the semi circular plate.
New combustion chamber cover plate gasket and felt seal. If the cover plate gasket fails it can leak combustion fumes into the blown heating air. Even if it looks in good condition always replace it.
Replace the screen. When fitting the screen ensure tab and screen seam do not obstruct vent and fuel supply holes. If the old screen is fairly clean its large area means it can be kept for use as an emergency replacement.
It is not essential but ideally when fitting the screen line up the tab with the slot, shown arrowed. This makes it easier to drive in a small screwdriver if screen removal is difficult.
The horrific pile of solid carbon deposits just from mechanical cleaning of the D1LCC that had the clogged exhaust port. This is the worst we have seen and definitely not typical. Modern fuels are so much cleaner it is unlikely to be repeated.
Another shot of the deposits. This photo included a few large bits that fell out of the exhaust pipe. The central pile was about 7 inches (20 cm) wide.
Eberspacher D1LCC reassembly
Reassembling the unit is the reverse of the disassembly process with just a few points to note.
Always fit a new gasket to the burner chamber.
The case needs to be fitted before the loom as the glowpin wires pass over part of the case.
When re-installing don't forget to fit the bottom sealing gasket.
Do not replace the M6 studs with stainless steel, they cause corrosion.
Stainless nuts and locking washers are ok.
Use locking washers not Nylock nuts, the nylon can melt.
Using Copaslip here and on the burner plate screws seems a sensible option.
Fuel filter in a D1LCC pump. You may have to use a pointed implement dug into the side of the filter to remove it.
Unscrew the 17 mm nut on the fuel pump inlet. Do not unscrew the nut at the end with the terminals.
D1LCC pump with filter removed.
Badly neglected filter with its replacement.
The condition of this filter is not normal, the filter can usually just be checked for debris and does not need to be changed.
You use any information and advice I give entirely at your own risk.
If you do not accept this do not use this site, go to an Eberspacher dealer.
I have tried to make it as accurate as I can but accept no liability for errors or problems caused by following our pages.
Some of the information is only suitable for people with a good aptitude for mechanical and electrical repairs. Any DIY involves some risk of accidents and you must decide if you are capable and can do it safely before carrying out any work.
You should also ensure your DIY is done to a professional standard in order to avoid creating potential hazards and insurance invalidation. Boat installations must strictly comply with Marine regulations.
Checking the Fuel Metering Pump Filter
The Fuel Metering Pump contains a fuel filter which should be checked and cleaned as part of the overhaul.
Thanks to Ian for sending his experience on cleaning the D1LCC Burner.
Given the amount of black stuff that came out of the top channels I could reach (mine was almost as bad as the one in your pictures!), this worried me. Then I spotted 2 holes in the plate. I took a piece of thick single core copper wire (stripped flat grey twin-and-earth domestic mains wiring cable) and bent a slight hook in the end. I fed this through one of the holes and raked it up and down while rotating it slightly each time. After a while I was able to shake out another pile of carbon deposits. I repeated this through the other hole and also through the small cut-out in the plate near
the burner. Then into the channels behind the ends of the plate. I got almost as much stuff out as I had from the easily accessible top channels, so I'm a lot happier with the cleaning process.