These "ignition" solenoids, (relays) are common for trucks, busses, RVs, industrial equipment etc. For these applications there are many things that need high current control including manifold pre-heaters and glow plugs to get engines started to air tank drain valve heaters to keep them from icing up in winter. They are for continuous duty.  

The duty refers to the coil design. Relays designed for starters that do have built in solenoids such as those found on older Fords are designed for short term operation, under a minute and to operate under lower voltages during the starting process where battery voltage may drop as low as 8-10 volts. Continuous operation of these starter relays at >13 volts usually does them in around 5 to 10 minutes. If really unlucky the melt down will short the coil out and since most do not fuse these coil circuits you will get to deal with other damage. Use the alternator warning light circuit as is often done on a Westy and you also get to replace the alternator and that blue wire. 

Dennis

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of Neil N
Sent: Tuesday, October 20, 2015 7:02 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: Continuous Duty Solenoid vs Starter Solenoid; Visual Difference?

> ....... Packaging for this part did not indicate that it was a starter
solenoid but I now
> have to wonder.

Yikes. This MAY be the part in question:
Link to princess auto:   http://tinyurl.com/qygenh8

Neil.

--
Neil n

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