Hi, With reference to jump starting a Motorhome has anyone put the starter pack straight on to the vans starter motor. The reason I ask is because when I broke down recently, by turning the key the vans starter was not activated. When the breakdown people arrived they put the starter pack straight to the starter to bypass the key.
Technical Jump starter.
- Thread starter ninian324
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Technical Jump starter.
It depends what the fault is and access to the starter termnal versus the battery.
The main terminal of the starter is connected directly to the battery on most modern starters with built in solenoid / contactors. Thus ther is little difference in there or the battery. It will give slightly higher voltage to the starter as there is one less bit of cable.
On very modern vehicles with stop-start, intellegent batteries or battery crash isolators it could cause problems. You need to follow the makers advice with these.
I have done similar on much older vehicles with separate starter contactors when the contactor failed, but just a jump lead from battery to starter as the battery was not flat.
Robert G8RPI.
Hi, After my breakdown I took the motorhome straight to the garage where they checked it out to see if they could find the problem why the van wouldn't start from the ignition key, absolutely nothing. So I was thinking of buying a Jump starter of my own so that if the same fault ever arose again I would be able to start it without calling out a breakdown service.
My Ducato TD10 diesel failed to start the other day, I thought the battery had failed as there was no sound from the solenoid.
I checked the solenoid wire with the key in position 2 and there was 12v, so I tapped with a hammer on the solenoid and tried it again, it started fine.
The solenoid is mounted above the starter motor and gets drips of water from the front grille and maybe from topping up the windscreen washer, which can eventually cause it to stick beyond the solenoid magnet's ability to move it.
I checked the solenoid wire with the key in position 2 and there was 12v, so I tapped with a hammer on the solenoid and tried it again, it started fine.
The solenoid is mounted above the starter motor and gets drips of water from the front grille and maybe from topping up the windscreen washer, which can eventually cause it to stick beyond the solenoid magnet's ability to move it.
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Copied from my posting on ninian324 s other current thread "Won,t start".
"When I suffered from starter problems in the past, there was too much resistance in the solenoid circuit. I got a clunk as the pinion was engaged with the ring gear, but there was insufficient power to allow the solenoid to complete its stroke and close the motor contacts.
I suspect that when your emergency technician applied a jump start connection at the starter motor, he just connected to the smaller solenoid terminal. I think that it could be more difficult to connect to the main battery terminal on the starter, and then energise the solenoid."
This is similar to the direct wire technique described by Robert G8RPI, in the final sentence of post #2 above. On an x250, the direct wire technique would be easier to carry out by connecting to the jump start point, rather than to the battery under the cab floor.
If attempting this method, it would be much safer if the wire was initially connected to the small (solenoid terminal) on the starter motor, before completing the circuit at the jump start point.
The risks of shorting circuiting the starter battery should be carefully considered. It is not incoceivable that the vehicle could be set on fire, and possibly destroyed.
"When I suffered from starter problems in the past, there was too much resistance in the solenoid circuit. I got a clunk as the pinion was engaged with the ring gear, but there was insufficient power to allow the solenoid to complete its stroke and close the motor contacts.
I suspect that when your emergency technician applied a jump start connection at the starter motor, he just connected to the smaller solenoid terminal. I think that it could be more difficult to connect to the main battery terminal on the starter, and then energise the solenoid."
This is similar to the direct wire technique described by Robert G8RPI, in the final sentence of post #2 above. On an x250, the direct wire technique would be easier to carry out by connecting to the jump start point, rather than to the battery under the cab floor.
If attempting this method, it would be much safer if the wire was initially connected to the small (solenoid terminal) on the starter motor, before completing the circuit at the jump start point.
The risks of shorting circuiting the starter battery should be carefully considered. It is not incoceivable that the vehicle could be set on fire, and possibly destroyed.
