Unregistered users may browse the website, but in order to participate in the forums a user account is required. Click HERE to email the webmaster and request an account. The National DeSoto Club uses real names rather than pseudonyms. Notify the webmaster of your user name preference (Johnathon Doe, John Doe, etc) and password request.
48 automatic choke
My choke is not operating properly. It is adjusted properly and the bimetal seems to work at least partially. The electromagnet does not work. I have hooked a jumper to it from the battery and I can hear it click but it doesn't move the lever. I have looked at drawing of it and it appears that it should be attached to the shaft so I am speculating that it is not attached but can be reattached.
Another part of my problem is removing the choke from the manifold. The brass nuts are firmly attached to the studs and I am afraid that I might twist off the studs if I apply much pressure.
So my questions are (1) can the choke be repaired? (2) how can I remove the nuts without twisting off the studs?
These chokes can not be repaired. To remove the choke Iwould spray PB Blaster on the studs and nuts to loosen any rust and then slowly try to remove the nut. There should be a gasket under the body of the choke this is needed.
Di you setup the choke lever correctly and do you have any instructions onhow to setup the choke correctly?
I also have several NOS Sisson choke if you need to replace yours Yes these are not cheap asking $170 and this includes shipping
valley Forge, PA
I just replaced the choke on my 41 DeSoto. Its the same one you use on your car as well. Made by Sisson. Soak the nuts in a good penetrating oil for a couple of days and then try to remove them. Can't hurt if they don't move because you will have to drill them out anyway. I ended up having to drill mine out and put in new ones. When you reinstall your choke, make sure you use a high heat gasket so the metal spring does not come into contact with the exhaust manifold.
These chokes aren't cheap. Take your time looking for one to get a decent deal. I have seen them ranging from $165 to $250. There is one on eBay right now as a matter of fact. I think it was in the $180 range.
I still don't have the electric wire set up to my choke yet... but it works anyway from the engine heat. The wire delivers an electric impulse to slam the choke butterfly closed for a split moment when starting the car. I live in the Southeast and maybe its not as important here.
Good luck and I would love to hear how your story turns out.
1937 4 door Touring Sedan
1941 DeSoto Deluxe 2 Door Sedan
It's Delightful, It's DeLovely, It's DeSoto!
Thanks Richard and Dean. I know how to adjust the choke. I have the service manual and an old Motor repair manual. I think I will try a small nut splitter to remove the nuts. Richard I need to get with you to purchase one of your nos chokes. The car is ok in warm weather but hard to start and keep running in cold weather until it warms up.
Jim: I have the sisson testing stand and if you want to send me your used unit I could but it on the stand to se if it is still working. The stand tests to see if the arm movement fall withint a specific range based on the current temperture
If you do need to purchase a NOS unit I will also send along a copy of the sisson choke manual and also a Sisson Pin that is used to setup the choke.
I am still working on removing the brass nuts. I am thinking of using a nut splitter. Can’t find a small one locally so it looks likeAmazon. I will certainly take your offer when I remove the choke.
I also working on the passenger side window. It is cracked and the chrome that the vent window seals against broke off and fell inside the door. I have the window out now and it appears that the chrome seal can be repaired.
I have not used mine on the '47 Suburban for 15 years. I took it off and just wired the carb choke open. I pump the gas pedal 3 or 4 times in the AM and it firs off just fine. One does have to let it warm up for a few minutes or drive with a light foot until the manifold warms up. Of course I am in San Francisco where it is 65F winters-summer...
I have a bunch of those Sisson Chokes floating around. I should check them to see if they all work if Rich is getting $175 each for them!
Funny, I went to school with one branch of the Sisson family in High School...He dad was a Grandson or Great Nephew of the man that designed that choke...his dad did a lot of work with magnetos and old mechanical fuel injection.
Yes if you look on Ebay for Sisson Chokes NOS ones from mid 30's-50's for our DeSotos around even higher and the the sisson chokes for the 1949-mid 50's plymouth that mount in front of the car are all going for well over $225 by the major vendors. So I think my price is in par with what other venders are charging. I have purchased these over the years but they were not cheap even then.
So if you need someone needs one then go to the vender of choice. I judge my prices by what other people charge and will undercut them. I also have the testing stand and tools to test these old chokes and I doubt that any of the venders even have the old original Sisson Choke testing stand and the adjustment tools for the regular sisson choke and also the one that was used onthe eight Cylinder Chrysler and the Airflows. i do have these and have demoed them numerous times at Hershey and at our NDC conventions. These items do not come available so I purchased them to guarantee that when I sent an item out to a person it is working correctly.
I have people specifically ask me for NOS Sisson chokes because they have a Senior AACA car and they expect me to give it to them at a real low price. NO, If they want a perfect item then you have to pay the going prices to support what you want. So they pay alot of money for the car but do not want to pay for an item to make their car correct and to be an AACA NAtional or Grand National Car.
This is probably a dumb question, but...
wouldn't it be easier and cheaper to use a manual choke cable and install the pull-knob under the dash?
That's how cars were for a very long time.
Rich, sorry if I offended you...but I think you were taking my comments to serious. If one has a car and they are looking for those last 5 points to 99 points then yes, you pay what it takes.
Like I said, unless you live in a really cold environment and need it...most of the cars will run just fine without it if you let it warm up for a couple of minutes at idle.
In my case, I moved to the later Carter carbs that were used on some Dodge models I think it was that use the hot air choke and more important to me the manual dashpot.
On the heavy cars like the Suburban with a fluid coupling and city stop and go traffic the electric dashpot that is not adjustable was more of a concern than the choke.
I have paid and paid dearly on some of my cars for NOS parts. But most people really don't need it.
Like the saying goes the last 5 points cost as much as the first 95...