Diesel heater/battery guru needed

N

nimrod1230

Well-Known Member
Joined
30 Dec 2005
Messages
305
Location
Oxfordshire
Visit site
Heater stopped working. Tried on a pro test rig, ran fine with gas analysis spot on. Reinstal, check pump, fuel quality, electrical connections, all look immaculate but heater won't fire up. While checking connectors the heater tried a start and one of the three sealed domestic batteries started fizzing. There were bubbles and liquid being forced out of a top seam. What the heck would cause this and does it have a direct relationship to the heater problem?
 
nimrod1230 said:
Heater stopped working. Tried on a pro test rig, ran fine with gas analysis spot on. Reinstal, check pump, fuel quality, electrical connections, all look immaculate but heater won't fire up. While checking connectors the heater tried a start and one of the three sealed domestic batteries started fizzing. There were bubbles and liquid being forced out of a top seam. What the heck would cause this and does it have a direct relationship to the heater problem?
Click to expand...

I don't know what has caused you're battery problem, but diesel heaters can be very sensitive to available voltage. So if the batts knackered the bolts drop and it won't fire up.

I had a batt melt on me when the alternator rectifier failed a few years back. I couldn't work out what the acrid smell was at the time.
 
You need a volt meter to check voltage right at the heater power input terminals. My guess is that the battery voltage is dropping too low for the heater when start plug is drawing current. If voltage is too low then compare to voltage at battery terminals. If this remains OK with heater on start cycle then it is a wiring fault so check volt drop at fuse board etc. Don't forget the negative return line. It does all sound a bit like a dud battery though. Remove the dud one and try again. Note however that the dud battery may have discharged others in parallel so recharge and test again. olewill
 
nimrod1230 said:
Heater stopped working. Tried on a pro test rig, ran fine with gas analysis spot on. Reinstal, check pump, fuel quality, electrical connections, all look immaculate but heater won't fire up. While checking connectors the heater tried a start and one of the three sealed domestic batteries started fizzing. There were bubbles and liquid being forced out of a top seam. What the heck would cause this and does it have a direct relationship to the heater problem?
Click to expand...

Low voltage will stop it starting, as stated. If the battery is fizzing and leaking from a seam it is knackered.
 
Hm, thanks for your thoughts. I assume the general consensus is to change all 3 batteries in the bank at once? They are 4 years old, pampered, on shore charge most of the time and never discharged beyond 30/35%. Not the most technical or expensive but highest power for the dimensions at the time, Enduroline. Is 4 years a reasonable lifespan in the circumstances?
 
Four years is not very long for well maintained batteries, you could check your warranty. As suggested, isolate the fizzy one and try again. If the remaining batteries​ are ok, I would just replace one unless you are particularly flush or going on a world cruise.
 
nimrod1230 said:
Hm, thanks for your thoughts. I assume the general consensus is to change all 3 batteries in the bank at once? They are 4 years old, pampered, on shore charge most of the time and never discharged beyond 30/35%. Not the most technical or expensive but highest power for the dimensions at the time, Enduroline. Is 4 years a reasonable lifespan in the circumstances?
Click to expand...


Those are just ordinary leisure batts made by heaven knows who. 4 years is good if they have been cycled much, not if they haven't (as you say).
It sounds as though you have a shorted cell in one which certainly could originate from a manufacturing fault, but can also result from being left discharged.
Can't you remove the fizzing one and just carry on with two while you see if any chance of warranty replacement (don't hold your breath)? You appear to have plenty of total capacity.
However if the other two are in good condition, I'm surprised the bad one is able to drag them down enough to stop the heater starting. It suggests something has happened to knacker all 3.
Have you tried to start the heater with the fizzer removed? Seems the obvious first step.
 
I've bitten the bullet and 3 new batteries have been delivered today. Explorer AGM this time. Will fit and then if heater problems continue will get the pro's in.
 
PaulRainbow said:
Check the glow plug, check all of the 12v power connections (remove, clean refit).
Click to expand...

+1 for cleaning the terminals - Do include the battery terminal clamps, they're often forgotten.

I had an interesting experience a few days ago. I'd heard the charge warning buzzer going feebly at idle, but was OK under way, then a day or two later, it wasn't OK under power. "Bugger," says I, "The alternator's fecked." So I took it off and noticed that the connections were "a little" rusty. A good clean and refit later and it's fine. Voltage showed 14.2 volts when I had just started, rising quickly to 14.3, and no sign of the buzzer except when I turn on the "ignition"
 
By way of a full stop the heater is back to normal. Rechecked the fuel supply and found this time a distinct lack of fuel per cycle. New pump fitted and after 4/5 starts to fill the pump and line all back to roaring normal.
 
You must log in or register to reply here.

Share this page

Top