: carburetor question

08-06-11, 05:39 AM
Hi all,

So I got myself a new service kit for my 68 DeVille carburetor, and did everything by the book, I serviced the carburetor, replaced needles, seals, ball, jet, valve and so on, till the time I was about to install it back on the engine....

The gasket appears to be wrong.

Have a look at the picture. and tell me what you think....end result, engine does not start when I install it. I am thinking the gasket is blocking something. There are too many tiny things on the carburetor but the seal seems to only have three openings. Someone who has seen this before, may be able to help me out here. Cheers

Angelo Gargarello
08-06-11, 06:35 AM
I am no expert on carbs but you might want to check that you have all the correct setting to allow the right amount of fuel being that you did some what of a rebuild; When I did mine I had to change some setting on it because I was not getting any fuel at all. also blow some air through it to see if you have dirt or any other crap that could have made it's way in when you where putting it back together. Hope it helps best of luck.

08-06-11, 08:28 AM
This may help?
Where is the old gasket? Does it look like the new one?
Did the fuel bowl fill?

08-06-11, 08:56 AM
As amunderdog suggests, itīs important comparing old gasket with new one. If you have bought a generic Rochester Quadrajet rebuild kit, not all of them would fit 68 cadillacs: http://motors.shop.ebay.com/i.html?_nkw=rochester+quadrajet+gasket&_sacat=&_dmpt=Motors_Car_Truck_Parts_Accessories&_odkw=rochester+quadrajet&_osacat=0&bkBtn=&_trksid=p4506.m270.l1313

This is the correct gasket for your '68 cadillac according to Rockauto: http://www.rockauto.com/catalog/moreinfo.php?pk=120920 It costs less than $ 3.00 so you could try with it.

You may also modify new gasket to make holes as similar as possible to the old one. If then, the car does not start yet, you should check, as Angelo says, if the right amount of fuel mixed with air arrives at cylinders. Maybe no fuel or very small amount; maybe carb is choking by too much fuel; maybe air inlet is closed by mistake. If someone tried to start the car while you are checking how is exactly behaving the car, this would help you to find the problem source. First check coil and plug wires are correctly connected to be sure there is spark in the cylinders.

08-06-11, 09:32 AM
Doing some more research, just found out something interesting.

The carb fitted on my 68 caddy belongs to 72 deville, part number 7042230. I think whoever had it before me made it work by manually cutting holes, these are pretty much gone now while removing the carb from car, but I'll try to put the pieces back together and see what I come up with, but looking at the condition of old gasket, it's almost impossible.

My other options are to buy a new or refurbished 68 deville original or after market carb which actually fits....Any idea who may be able to supply this? bay was no luck and all edelbrock listed say they don't fit 68 Deville

08-06-11, 09:43 AM
If your carb is for a '72, then the advised gasket should be this: http://www.rockauto.com/catalog/moreinfo.php?pk=120961 (not very different to your new one)

You can buy a '68 caddy remanufactured carb from Rockauto: http://www.rockauto.com/catalog/moreinfo.php?pk=1126069 for about $ 250, or you may try in the Official thread For Sale / Wanted parts. Maybe someone has one to sell.

08-06-11, 10:04 AM
Alright, now we are getting somewhere....

From the above link, I am at least now able to compare the two (original 68 and mine), they are generally the same with one big difference. The one on my car has couple of extra channels, which I think make all the difference, unless I can join millions of tiny pieces of old gasket (yes I said millions :) it would be hard to know what was done to it to make it work....

08-06-11, 10:36 AM
here we go, this is what I was able to piece together, The one missing part of it is what was on the base, looks nothing like the one for 68, I guess this is the one I need.....

08-06-11, 12:07 PM
According to this link: http://www.recarbco.com/technical/rochester/qjet.html you are right: Itīs a 72 non California Cadillac automatic carb. so your new gasket should work. Maybe if you adapt it like the '72 Rockauto gasket by carefully using a cutter :rolleyes: ...

08-06-11, 12:10 PM
I always liked and had good luck with Edelbrock Performer Series Carbs
Never had much luck rebuilding old carbs.


08-06-11, 04:47 PM
I dought its this base gasket thats causing your issue. Have you pulled the throttle lever back to see if any gas is shooting into the carb?

08-06-11, 06:53 PM
Oh yeah, the throttle is shooting gas alright, I used a few drops of liquid this morning called cold start aid, the directions said just spray it into the air intake, which I did and the car tried to start.

By tried to start, I mean I got a few extra quick revs buts than the whole thing went back to the same old....

08-06-11, 07:43 PM
So it will try to start with the cold aid but wont if you pump the gas?

08-07-11, 02:10 AM
It Liiiiiiiiiiiiiiiiiiiiiives

Got it to run finally. there were two things. Wrong gasket and a lose vacuum connection

First, I compared the pictures referred by CADforce69, this showed me that the big bulky base gasket with black adapters was not needed at all, so I removed it and the carb sat nicely, second was the lose connection. What csbuckn said made me think, if mechanics are fine, there has to be something holding it all back, maybe a leak, so I cut off the ends of each vacuum pipe and placed it all back, all connections snug and no leaks, another crank and it started nicely with no rough idling or any other issues, just great.

It blew a bit of smoke which I think is WD40 that I injected through plug holes before starting it, but finally it lives after 10 years in storage.

Now off to more fun stuff like vacuum, brakes and convertible top....

By the way, I am also re-chroming the spoke wheels myself using a DIY kit...wish me luck, will keep all posted with pictures.

08-07-11, 12:51 PM
Glad to know you started it at last and it runs fine :) Another one which comes back to the World of the Living. We would love to be kept informed about your progress and see as much pics as possible ;)

08-08-11, 07:25 AM
Glad you got it started. I was going to suggest dumping some gas down the carb to get things started. Definitely tell us more about the chroming process when you have some results.