nicho
RIP
After a few minutes of normal operation, the fan on our Eberspacher starts hunting/surging (speed increases and decreases every 2/3 seconds or so). Any ideas welcome please.
Surging Eberspacher
- Thread starter nicho
- Start date
volvopaul
Well-Known Member
Partially blocked fuel filter or low level in your main tank.
nicho
RIP
Thanks Paul. Will check the filter, but tanks are full for winter.
matthewriches
Well-Known Member
Can you get a video of the symptoms if you're still having problems?
nicho
RIP
Boat's 150 miles away from home - have someone checking it for me, probably next week. Will update if fixed.
nicho
RIP
Sorry chaps, resurrecting this one again. The unit has been stripped, a broken gasket (somewhere inside) changed, fuel lines cleared, fuel filter cleaned etc. Fired up, runs fine for 8/10 minutes, then the fan starts surging as before. Engineer says no fault codes, and it could be the ECU. This costs around £400 (D4S unit ecu expensive), with no guarantee it will fix the problem. Anyone any final ideas before we go down the new ecu route? (which is evidently on back order anyway). Any further help would be appreciated. Thanks.
elton
Well-Known Member
Try running it on diesel instead of paraffin.
nicho
RIP
Sorry, am I missing a joke here? It runs direct from the boats main diesel tank!
Seastoke
Well-Known Member
he means run it on paraffin for a short time
Hadenough
Well-Known Member
Have you cleaned the horrible little filter in the fuel pump?
Talulah
Well-Known Member
How old is the unit? Over a period of time the burner cokes up. It’s easy enough to dismantle the unit and clean the burner unit. This is why some people run a litre of Paraffin through to clean out the unit. However there is a part at the rear end of the burner unit that it’s not possible to physically get at. The rest of the burner can look clean. Some people try cleaning with caustic soda to shift the solid lumps of soot.
I very much doubt it’s the ecu.
I very much doubt it’s the ecu.
Talulah
Well-Known Member
Anyone you know have a D4? You could try their ecu.
nicho
RIP
Thanks. I believe the engineer has had the unit apart and thoroughly checked it, cleared the fuel lines, cleaned the filter and replaced one gasket, all to no avail - he knows Eberspacher units well, and is scratching his head, especially as it shows no fault code. It was on the boat when I bought it, but it evidently looks like a relatively new unit, and it ran perfectly last winter. I will suggest the paraffin trick when I next speak to him on Monday. Having searched the web, I did see one other unit suffering the same problem, but there was no response to his question. Hope you are right about the ecu!
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nicho
RIP
As I understand it, the D4 ecu does not work on this higher output D4S. Really appreciate the input, thanks.
nicho
RIP
Other way around Elton, then I get it! Thanks.
