Having the wood refinished has meant the car has not been started
for a few months. However am I right in assuming that the automatic
enrichment device works regardless of outside temperature. Last
fall it worked fine in the cooler temps but now with 90 f temps I
cant get the car started. Oh for a manual choke.
In reply to a message from sportscarguy sent Sun 15 Aug 2010:
Kim,
You could check to see if your AED is ON by pulling the
spade connector off of the sensor with the ignition turned
to the ON position. When you put the spade connector back
on you should hear a click.
If it works try holding the accelerator pedal about 1/2 way
down and see if it will start.
Just a guess.
Best,
Shell–
The original message included these comments:
for a few months. However am I right in assuming that the automatic
enrichment device works regardless of outside temperature. Last
fall it worked fine in the cooler temps but now with 90 f temps I
cant get the car started. Oh for a manual choke.
Kim R.
In reply to a message from sportscarguy sent Sun 15 Aug 2010:
Kim -
The solution to this is actually quite simple. The wire
from the AED to the SU thermoswitch is simply a ground wire.
If you take that wire and run it to a switch in the cockpit,
with the other end wired to ground somewhere behind the
dash, then you can control it manually as needed.
I believe this fix was put in an official Jaguar circular in
the 1960s.
Alternatively, when it is warm in the summer, just remove
the electrical lead from the Thermoswitch (located on the
water rail above the thermostat) and wrap it in some
electrical tape (so it won’t ground accidentally and turn
the AED on). This is the easy quick fix, just reattach in
winter…
Note that the SU thermoswitch is exceptionally unreliable!
I agree with your experience. I have rebuilt quite a few of the thermal
(Otter) switches that control these starting carbs. When I started I set
them as they were originally designed, to turn off at 35� C (95�F).
However, there is a certain amount of hysteresis in the system. Once it
turns off at 95� the temperature has to drop to 75� or 80� before it will
turn on again. A customer in Florida complained that his carb didn’t turn
on in the summer. Personally, I always felt that my carb turned off too
early, leaving the engine struggling to idle until it fully warmed up. So I
tried different temperatures and settled on 60� F as the temp that makes my
car run the best. Bypassing the Otter switch with a toggle switch is
another solution. Of the 5 or so cars that I have owned, ALL of them had
toggle switches installed by the previous owners.
Having the wood refinished has meant the car has not been started
for a few months. However am I right in assuming that the automatic
enrichment device works regardless of outside temperature. Last
fall it worked fine in the cooler temps but now with 90 f temps I
cant get the car started. Oh for a manual choke.
Kim R.
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In reply to a message from Mike Eck sent Sun 15 Aug 2010:
My toggle switch came with the car and works great. It is also a
cold weather anti theft and anti valet parking person feature.
P.–
Peter J. Smith, 1966 3.8S MOD
Carson City Nevada, United States
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In reply to a message from Mike Eck sent Sun 15 Aug 2010:
What I would really like is a simple throttle jack that
would only increase the idle to say 1200 RPM until the
engine was up to normal temperature. The AED dumps a lot
of extra gas into the engine for enrichment but what would
work after some engine temperature is achieved is a fast
idle set up. Any shade tree engineers out there? My AED
works fine on cold start up then in a mild climate cuts off
after the first 3 blocks and the engine dies at stop signs
unless manually turned back on with the toggle switch.–
The original message included these comments:
on in the summer. Personally, I always felt that my carb turned off too
early, leaving the engine struggling to idle until it fully warmed up. So I
tried different temperatures and settled on 60� F as the temp that makes my
The AED is adjustable, so you can set the fuel-air ratio so it doesn’t dump
a lot of extra gas in the engine. When properly adjusted, the engine starts
easily and idles fast without being excessively rich. Try backing out the
adjustment nut and see if it doesn’t help your situation.
engine was up to normal temperature. The AED dumps a lot
of extra gas into the engine for enrichment but what would
work after some engine temperature is achieved is a fast
idle set up. Any shade tree engineers out there? My AED
works fine on cold start up then in a mild climate cuts off
after the first 3 blocks and the engine dies at stop signs
unless manually turned back on with the toggle switch.
What was I thinking? Unlike what I just said, you should turn the nut
CLOCKWISE (down) to make the mixture leaner. Full instructions for proper
adjustment are in the manual.
The AED is adjustable, so you can set the fuel-air ratio so it doesn’t
dump a lot of extra gas in the engine. When properly adjusted, the engine
starts easily and idles fast without being excessively rich. Try backing
out the adjustment nut and see if it doesn’t help your situation.
Mike Eck
New Jersey, USA www.jaguarclock.com
'51 XK120 OTS, '62 3.8 MK2 MOD, '72 SIII E-Type 2+2
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To avoid bore flushes which is detrimental to the cylinders, I turn off the ignition and immediately turn it on again, after about 10 secs after starting. This shuts off the AED but leaves the engine struggling somewhat. I leave it warm up for a few minutes, and then drive off as normal.
I have had the engine compleley rebuilt and have a switch under the dash for the AED . I turn it on when starting and turn it off a a couple of minutes later . Keep foot on gas pedal at about 1000 rpm . Minimum amount of gas in the cylinders . Motor needed new block, everything that went back was new . The engine and other mechanical upgrades came to $12000. Lost interest in the car, it is for sale .Probabley one of the best Mk 2 s around .
Kim.
peder
May 10
To avoid bore flushes which is detrimental to the cylinders, I turn off the ignition and immediately turn it on again, after about 10 secs after starting. This shuts off the AED but leaves the engine struggling somewhat. I leave it warm up for a few minutes, and then drive off as normal.
Yes, that is a common way to desl with it as well, but my way works too.
Not really in the market for another Jaguar (as I have >20), but a perfect 4,2 Mk10 or 420G would be an exception. I have 3 already but really like them. Don’t have the Mk2, but my father’s S-type.
What colour is your Mk2?
Peder