13.8v at battery. Is it enough to run lpg sat nav and lights

[Sir Brixalot]

I'm having a problem where the lpg suddenly cuts off whilst driving. After stopping and checking the battery it's virtually flat despite being full earlier in the day. Should 13.8 be enough to handle dipped beams a satnav and lpg. It's put me in a couple of tricky positiions. I can get going again on petrol but at 16mpg it's very expensive on a long trip

[R0B]

Is your battery charging when the van is running? If yes then your battery might not holding its charge. To check remove the battery charge it.Check voltage, leave battery stood for 24hrs check voltage again.If there's much difference replace battery.Or it could be draining to earth.How do you manage to start it on petrol with a flat battery.?

[Sir Brixalot]

I checked before I switched to lpg and battery was charged. An hour later on lpg with lights and satnav battery was drained. Battery is a Bosch s5 a couple of months old. To get it going I jump from leisure battery and put petrol in the carb if necessary. Does the solenoid on the vaporiser draw much current. It seems that the drain is happening only when I'm on lpg

[itchyfeet]

13.8V is not flat or full, thats alternator charging volltage ( which will fall quickly after switch off)
flat would by 12.1 12.2 ish, I gave run my van at under 12V when my alternator packed in.

What is the voltage when it cuts out?

[Sir Brixalot]

Think I might have tracked it down. I had a radio fitted just before I left by a mobile fitter. The wiring is a mess and a 30a fuse has been fitted and I found a discarded blown 10a. I've pulled the harness and I'm hoping that's it. I put my trusty gunsons diagnostic on battery and it's good