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Re: Auto choke electrical heating - why?

Posted: 24 Apr 2015, 13:45
by CJH
CovKid wrote:That makes a lot of sense since otherwise the coil is being heated all the while the ignition is on which always struck me as a complete waste if not shortening the life of the coil. Once the engine is warm, its not needed.

That's not how it's described in the Haynes book of carbs.

Haynes wrote:...the electrical supply to the choke is made through a coolant-heated thermal switch... ...When the coolant reaches a preset temperature, the thermal switch cuts out the electrical supply (VW only), and the coolant flow remains the only source of choke heating.

Re: Auto choke electrical heating - why?

Posted: 24 Apr 2015, 17:03
by kevtherev
65 deg C iirc, is when the heaters are switched off by the thermo switch in the stat housing.

6-8 mins is the time it takes to open the choke, depending on the ambient temperature.

Re: Auto choke electrical heating - why?

Posted: 24 Apr 2015, 17:50
by itchyfeet
Late van has choke heater on ignition cct, haynes shows it on switched cct

Re: Auto choke electrical heating - why?

Posted: 24 Apr 2015, 18:30
by CovKid
Be interesting to determine then if power to the electric choke is actually removed when engine up to temperature.

Re: Auto choke electrical heating - why?

Posted: 24 Apr 2015, 18:54
by kevtherev
Should be, its on relay No. 1
Triggered by said switch

Re: Auto choke electrical heating - why?

Posted: 24 Apr 2015, 19:05
by itchyfeet
Not on a late van in my experience, permanent ignition connection.

Re: Auto choke electrical heating - why?

Posted: 24 Apr 2015, 20:06
by CovKid
As an 85 model, mines on the cusp. Will connect a small LED and see if it goes out. Be very surprised if it does. Certainly on the bugs it didn't go off.

Re: Auto choke electrical heating - why?

Posted: 24 Apr 2015, 22:30
by kevtherev
Should be controlled by the relay.
It controls three heaters
Either your switch was bust or the relay was.

Jus' sayin'

Like I wrote earlier, mines manual now
I trigger the relay.

Re: Auto choke electrical heating - why?

Posted: 25 Apr 2015, 07:01
by itchyfeet
My late engine loom is obviously origional, what2ds is identical and I have seen another too, choke heater is NOT with the manufold heater and part load duct heater, its ignition 12v with the cut off valve so permantly on.
Haynes shows all three heaters on the thermoswitched cct so mybe early vans were wired that way.

in this pic you can see the two yellow ignition pos connectors for air cutoff and choke daisy chained in black wire.
While we are on the subject both of tyese circuits have NO fusing so worth adding some

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