Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Auto choke issue?

The car has been stood outside all this week, but I jumped in earlier on, and after the usual start routine, it roared into life. but by the time I got to the end of the street, the auto choke appeared to have given up the ghost - as soon as I took my foot off the throttle it died - which made changing gear interesting.

I was taking my lad to a party, so rather than getting stranded somewhere I popped home and stoked up the old merc for the task.

my car is a cvh, with K&N filter - is this just the cold starting issues that I have read about with the K&N or a cvh auto choke glitch, what do you chaps think?

Depends on your carb. DFT32/34 the electric autochoke can be adjusted for how long it stays on after the engine fires - assuming it is working, though they are quite reliable. It is time related how long it stays on, it does not depend on how much the engine has warmed up. Though if the ambient temp is above around 20C the choke will not activate anyway I believe - chance would be a fine thing!
Loosen the three screws on the body of the bimetallic mechanism. Then viewed from the front of the car turn it a few degrees anticlock to increase the length of time it stays on, you will need this in cold weather. There will be three notch marks on the body of the carb and one on the body of the bimetallic mechanism. The middle one is normal position, then anticlock for winter and clockwise for summer in Italy!
Roll on spring - PJB

Cheers pjb,

Mine is a leanburn cvh with the weber tld carb (28/32?)

I have just started the car up now with no probs, I'll go for a spin and see how it goes

Well, service seems to have returned to normal, I guess it was just cold, and I maybe deactivate the autochoke, with an inadvertant throttle press.

I think it was the cars way of complaining about a lack of use this week - whenever I dont drive it for a few days it throws up some glitch or other

The TLD has a water temp activated choke release, but there is the same adjustment method. Thus it is possible to increase the water temp at which the choke fully releases. PJB

I used to have an Escort many years ago with a CVH engine.
The auto-choke was notorious for failing.
Mine started to play up by not resetting to cold start after it cooled down, and a light tap with some wood "released" it.
Many people changed them for manual choke.
The device is simply a spring that returned the choke to normal mix setting when it warmed up from it's water supply. When it cooled back down it reset the choke to a rich cold start setting.
I replaced mine with a service kit and it worked fine until I sold the car.

From what I remember, the coil/spring mechanism inside was a bi-metallic type that distorted due to different expansion of the metals used. When it cooled it retirned to its original position.
I can vaguely remember dismantling mine and that's what I seem to remember.

My initial re-test of the car on sunday suggested all was well, but this morning I did the school run with the kids on board. The car started normally and the auto choke cut in as normal. but the idle speed dropped to probably 500rpm after a few mins (when I next stopped at lights) and 20 mins later it was still painfully slow. There was some popping from the exhaust on the over run too. there was no misfire as such but some hesitation.

Then back in the car an hour or so later and its running sweetly again.

Do you think this might be more of a carb/mixture issue or plugs leads/dizzy cap? - I havent checked these yet as in work clothes!

What is your normal idle speed? The choke should not drop it below this. I cannot see how anyway (I await to be corrected :))

Is the throttle cable free and linkage freely moving? Can it return to its intial position OK?

Fuel pump perhaps or timinig?

Randam thoughts that may help or not!!

Hi Richard,

normal idle speed when warmed up is around 1000 on my cvh.

I am wondering if something is getting stuck - the car has been sitting out all winter, with less use than normal.

I have a day off tomorrow, so am grateful for any pointers in terms of things to check out, as this may save my time under the bonnet in sub zero temps