News:

Due to a technical issue, some recently uploaded pictures have been lost. We are investigating why this happened but the issue has been resolved so that future uploads should be safe.  You can also Modify your post (MORE...) and re-upload the pictures in your post.

Main Menu

1968 Calais choke coil

Started by Gene Beaird, March 29, 2023, 02:43:00 PM

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.

Gene Beaird

I keep thinking of this from time to time, but haven't done anything about it.  The choke doesn't work on our Calais.  While it still starts and runs, it's always a bit rich, and it would be nice to have it run just that much better.

I've tried off and on to try to find a replacement, but about all I've had any luck with are 'page not found' or choke 'conversion' kits that move from a divorced choke to one on the carb. Although the car will never be a 100-pointer, in my hands, at least, I'd really not like to convert unless it is absolutely necessary. 

I think the proper part is a Delco 7027092, but that may be only for 1967, so I'm not sure.  I'm not opposed to replacing just the bi-metal coil, if those here think that would work, and I do see some listed on quadrajet parts web site, but wanted to know if there's anyone here with a choke coil collection that has a proper NOS choke coil, or has better interwebs search-fu than I do.  Thanks.

 
Gene Beaird,
1968 Calais
1979 Seville
Pearland, Texas
CLC Member No. 29873

Steve W

Hi gene,
First, are you sure your carb is the one that came from the factory on your car? Before ordering parts, you need to check it out. There's a couple of great QJet videos on YouTube that show you where the number is stamped and how to decypher exactly what you have. And isn't there a section covering the choke in the shop manual? I don't have mine handy at the moment.
Steve Waddington
1968 Coupe deVille
North Hollywood, CA
CLC Member # 32866

TJ Hopland

Is 68 like the earlier 70's where the coil is in either a rectangle or round well in the intake?

Thinking about what he wrote, choke doesn't work but runs rich?  Maybe we need a little longer description of the sequence of what is happening or not happening.   Walk us through a cold start till its running right assuming it eventually runs right.
StPaul/Mpls, MN USA

73 Eldo convert w/FiTech EFI
80 Eldo Diesel
90 CDV
And other assorted stuff I keep buying for some reason

Highwayman68

Gene can you please provide a picture of what is in place now.
1968 Fleetwood Purchased in 1981

Gene Beaird

Steve, the car is 99.9% original.  It's the one I my avatar.  Bought new by my Grandfather, and for several decades, my Dad and I were the only ones to turn a wrench on it. 

TJ, yes, it's in a well in the intake manifold.  The coil no longer reacts to heat, so I can adjust it so that it's on, or off.  Let the car warm and pull it off, and it slowly closes the choke flap.  There is a nice bit of discussion of the choke operation and adjustment on pages 6-67 and 6-69 through 6-70 of the FSM.  The choke is adjusted, it just does not react to heat, which is why I'm looking for a replacement.  If I can find, and just replace the bimetal coil, I'll do that.  Otherwise, I'd like to find a replacement choke thermostat assembly. 

Picture, as requested:

Gene Beaird,
1968 Calais
1979 Seville
Pearland, Texas
CLC Member No. 29873

Steve W

That's quite the family heirloom, Gene! Great stories too I bet!

Yours looks just like mine, but mine still works, so I've never looked into it at all. Sorry I can't help.

I do have a question though... have you ever taken your fuel supply line off of the carb and noticed what type of fuel filter is in there? I only ask because I did and it looks like a little steel mesh basket. I was looking at replacing it because I saw one that has a little check valve in it, which lets fuel flow IN, but when you shut the car off, it doesn't let it flow back out, which should make the next start up so much easier!
Steve Waddington
1968 Coupe deVille
North Hollywood, CA
CLC Member # 32866

Gene Beaird

#6
Quote from: Steve W on March 30, 2023, 02:46:19 PMThat's quite the family heirloom, Gene! Great stories too I bet!

Yours looks just like mine, but mine still works, so I've never looked into it at all. Sorry I can't help.

I do have a question though... have you ever taken your fuel supply line off of the carb and noticed what type of fuel filter is in there? I only ask because I did and it looks like a little steel mesh basket. I was looking at replacing it because I saw one that has a little check valve in it, which lets fuel flow IN, but when you shut the car off, it doesn't let it flow back out, which should make the next start up so much easier!

Steve,

Yes, we have some good stories.  My Grandfather actually got the car after having the oil pump fail on him on the way from Houston to Wichita, Kansas, in his 50's Cadillac.  Happened near Austin.  He got towed into a dealership in Austin, and I guess when they told him what the problem was, and the solution, he walked out into the parking lot and picked this blue Callais out so my Grandmother and he could continue their trip to visit my uncle and his family in Wichita. 

The car got passed to my Dad after my Grandmother passed away, and to me when my Dad passed.  We haven't done much with it but keep it running since.  We have way too many projects in the shop.  I DO like to take it out for a trip 'around the block' on occasion, so would like it running as well as it can, hence the renewed query.

It's been a while, but I think I put one of the plastic screened filters in the carb during a tune up session years ago.  Haven't had to replace the filter in a while.  I think we have the usual 'leaking jet and rod well' issue, as I don't believe I fixed this carb before my Grandparents went back to Alabama (I used to fix and tune Q-jets in another life).  So while it takes a few cranks to start, it does run fine after that.  It's just that the choke butterfly is closed too far making the car always run a bit rich, and everyone knows rich always ends up in the crankcase as additional carbon. 
Gene Beaird,
1968 Calais
1979 Seville
Pearland, Texas
CLC Member No. 29873

Steve W

If the choke is closing when it's cold, at least that part of it seems to be working. It just doesn't open all the way when it's warm. Is there a way to take it apart and clean and lubricate the linkage/s before you go looking at replacing anything?
Steve Waddington
1968 Coupe deVille
North Hollywood, CA
CLC Member # 32866

TJ Hopland

#8
Did/does this car have the EFE / heat riser / flapper valve in the exhaust?   If it has/had one was that required to be operational to get enough heat in the intake to make the choke work?  Maybe that got stuck open and there just isn't enough heat to make it work like it should?

Maybe the crossover is just blocked with carbon?    Gene, do you have one of those IR temp gun things?  If so maybe someone with a similar year can take some temp readings around the intake and then you could compare to yours.   Maybe you will find that yours isn't getting hot enough and if thats the case you will know that a new coil won't help.   You would then either have to fix why its not getting hot or find one of the alternatives that doesn't depend on a hot intake like maybe electric as a work around till the real issue can be solved to put it all back original.
StPaul/Mpls, MN USA

73 Eldo convert w/FiTech EFI
80 Eldo Diesel
90 CDV
And other assorted stuff I keep buying for some reason

Daryl Chesterman

#9
The Delco 7027092 is the part shown below, which doesn't look like what you show in your picture.

    https://i.ebayimg.com/images/g/1cMAAOSwO-Jft1Rp/s-l300.jpg

This is a link to choke parts for Quadrajet carburetors, and it shows some of the divorced choke coils without the covers, but I don't know if any of them would work in your situation without seeing what yours looks like under the cover.  It doesn't specifically list your Cadillac, but that doesn't mean that one of them wouldn't work.  It might be worth a call to them, if you can give them your carburetor number, to see if one might do the job.

    https://quadrajetparts.com/quadrajet-chokes-c-128_23.html

Is it possible that the choke coil is working correctly, but the vacuum pull-off is not working to open the choke butterfly when the engine first starts?  When the engine first starts, the butterfly should open approximately 1/4" to 5/16" (whatever the spec is for your car) and this keeps it from running too rich initially, then the choke coil will open it the rest of the way as the engine warms up.  Have you checked the choke coil linkage to be sure it is not binding on the housing or any other place?

Daryl Chesterman

TJ Hopland

One thing some people forget to consider with these is the carb base gasket effects the adjustment / range of the choke so if this problem happened to start with the base gasket was changed that could be why.  There is some range I think in bending the rod but there is also a lot of range in how thick or thin the base gasket can be too. 

If the gasket hasn't changed in years and the problem is more recent that isn't likely the issue.  I',m mostly bringing it up for other people that may be having similar issues and find this thread in the future.
StPaul/Mpls, MN USA

73 Eldo convert w/FiTech EFI
80 Eldo Diesel
90 CDV
And other assorted stuff I keep buying for some reason

Highwayman68

Quote from: Gene Beaird on March 30, 2023, 02:12:36 PMPicture, as requested:



Every single Cadillac produced in 1968 had this setup so they are readily available on any parts car. I have a couple of spares, I will send you one.
1968 Fleetwood Purchased in 1981

Gene Beaird

Quote from: Daryl Chesterman on March 31, 2023, 01:26:05 AMThe Delco 7027092 is the part shown below, which doesn't look like what you show in your picture.

    https://i.ebayimg.com/images/g/1cMAAOSwO-Jft1Rp/s-l300.jpg

This is a link to choke parts for Quadrajet carburetors, and it shows some of the divorced choke coils without the covers, but I don't know if any of them would work in your situation without seeing what yours looks like under the cover.  It doesn't specifically list your Cadillac, but that doesn't mean that one of them wouldn't work.  It might be worth a call to them, if you can give them your carburetor number, to see if one might do the job.

    https://quadrajetparts.com/quadrajet-chokes-c-128_23.html

Is it possible that the choke coil is working correctly, but the vacuum pull-off is not working to open the choke butterfly when the engine first starts?  When the engine first starts, the butterfly should open approximately 1/4" to 5/16" (whatever the spec is for your car) and this keeps it from running too rich initially, then the choke coil will open it the rest of the way as the engine warms up.  Have you checked the choke coil linkage to be sure it is not binding on the housing or any other place?

Daryl Chesterman

Daryl,

Correct, the one I was initially looking at is not the same.  I am ~99% certain that the bimetal coil has failed.  I was hoping to find a replacement, so I could get in and get out, and not have yet another stalled project in the shop waiting for parts.  I guess I need to pull the coil assembly out and verify functionality.  Everything moves in there, and the vacuum brakes work as expected.  I guess I get to start 'playing' with a replacement coil-only.  Thank you. 
Gene Beaird,
1968 Calais
1979 Seville
Pearland, Texas
CLC Member No. 29873

Gene Beaird

#13
Quote from: TJ Hopland on March 31, 2023, 01:16:55 AMDid/does this car have the EFE / heat riser / flapper valve in the exhaust?   If it has/had one was that required to be operational to get enough heat in the intake to make the choke work?  Maybe that got stuck open and there just isn't enough heat to make it work like it should?

Maybe the crossover is just blocked with carbon?    Gene, do you have one of those IR temp gun things?  If so maybe someone with a similar year can take some temp readings around the intake and then you could compare to yours.   Maybe you will find that yours isn't getting hot enough and if thats the case you will know that a new coil won't help.   You would then either have to fix why its not getting hot or find one of the alternatives that doesn't depend on a hot intake like maybe electric as a work around till the real issue can be solved to put it all back original.

TJ, yeah, I have a FLIR camera I can use.  The car does warm up, and I'd expect that warming the engine to the usual operating range would at least cause some movement of the choke, whether the heat riser is working or not.  Besides, finding one of those, should I have a failed unit, I'd expect would be harder than finding a proper choke coil. 

The car isn't used that much, so I'd not do the electric conversion only to go back to the OEM setup when/if I found an OEM-style coil.  I did find what looks to be a replacement for a '70 Cadillac, but the ad seems kind of sketchy.  They show a picture of what looks to be a new one, yet mention that the one they have is a take off from.a '70.  That, and the fact that they want >$100 for the thing has me hesitating.  Thank you. 
Gene Beaird,
1968 Calais
1979 Seville
Pearland, Texas
CLC Member No. 29873

Gene Beaird

Quote from: Highwayman68 on March 31, 2023, 07:52:44 AMEvery single Cadillac produced in 1968 had this setup so they are readily available on any parts car. I have a couple of spares, I will send you one.

Mark,

Your inbox is full.   :)
Gene Beaird,
1968 Calais
1979 Seville
Pearland, Texas
CLC Member No. 29873

Highwayman68

Quote from: Gene Beaird on April 01, 2023, 09:54:54 AMMark,

Your inbox is full.   :)

Well that made for some fun reading and memories. OK Inbox cleaned out, space is available again.
1968 Fleetwood Purchased in 1981

Matti R

Quote from: Gene Beaird on March 31, 2023, 04:11:05 PMDaryl,

Correct, the one I was initially looking at is not the same.  I am ~99% certain that the bimetal coil has failed.  I was hoping to find a replacement, so I could get in and get out, and not have yet another stalled project in the shop waiting for parts.  I guess I need to pull the coil assembly out and verify functionality.  Everything moves in there, and the vacuum brakes work as expected.  I guess I get to start 'playing' with a replacement coil-only.  Thank you. 
Before any purchase it is good idea to pull the coil assy out and check inside. It is very very simple system so probably easy to identify the problem there.
Best regards,
Matti
CLC #33333
67 DeVille convertible Sudan beige
79 Seville
64 Sedan DeVille
66 Calais Coupe

Gene Beaird

Quote from: Matti R on April 02, 2023, 03:38:08 AMBefore any purchase it is good idea to pull the coil assy out and check inside. It is very very simple system so probably easy to identify the problem there.

Bolts are soaking in PBBlaster as I type!!   ;)
Gene Beaird,
1968 Calais
1979 Seville
Pearland, Texas
CLC Member No. 29873

"Cadillac Kid" Greg Surfas 15364

Just another alternative. I've got an NOS '72 choke. This can use the rod from your 68, bend ou one of the tabs and correctly replicate the choke you need.
Greg Surfas
Cadillac Kid-Greg Surfas
Director Modified Chapter CLC
CLC #15364
66 Coupe deVille (now gone to the UK)
72 Eldo Cpe  (now cruising the sands in Quatar)
73 Coupe deVille
75 Coupe deElegance
76 Coupe deVille
79 Coupe de ville with "Paris" (pick up) option and 472 motor
514 inch motor now in '73-

Gene Beaird

Quote from: "Cadillac Kid" Greg Surfas 15364 on April 06, 2023, 09:43:44 PMJust another alternative. I've got an NOS '72 choke. This can use the rod from your 68, bend ou one of the tabs and correctly replicate the choke you need.
Greg Surfas

Thanks, Greg.  Highwayman68 said he had a couple of take-offs and he offered one up to me.  Waiting for its arrival now. 
Gene Beaird,
1968 Calais
1979 Seville
Pearland, Texas
CLC Member No. 29873