Rock10 Posted November 15, 2022 Share Posted November 15, 2022 Does anyone know how to remove the main jets in a 1936 Series 40 Stromberg carb? Link to comment Share on other sites More sharing options...
carbking Posted November 15, 2022 Share Posted November 15, 2022 "Main jets" can refer to two different parts. The main metering jets are the first item seen when the plug is removed. These are unscrewed using a special "double D" socket. If the mechanic does not have one, a suitable replacement may be fabricated using a soft steel rod just slightly smaller in diameter than the threaded hole, and a hack saw and file. Simply machine a groove in the center of the rod to slip over the jet. DO NOT ATTEMPT TO REMOVE MAIN METERING JETS USING NEEDLE NOSED PLIERS! The main discharge jets a.k.a. main discharge nozzles, are exposed once the main metering jets are removed. About half the time, these may be pushed out from the top by use of a small plastic rod (handle on cheap eye glasses screwdriver). The other half of the time, they are removed, and ruined during the removal, by a slide hammer. Jon 3 Link to comment Share on other sites More sharing options...
Rock10 Posted November 16, 2022 Author Share Posted November 16, 2022 Are the main metering jets usually replaced in a rebuild? Link to comment Share on other sites More sharing options...
carbking Posted November 16, 2022 Share Posted November 16, 2022 Depends on the quality of the rebuild. As the jets are more expensive than Carter, Holley, and Rochester jets, many opt to not replace them. They certainly should be checked for wear; AND NEVER BELIEVE ANYTHING STAMPED ON A JET! Jon 1 Link to comment Share on other sites More sharing options...
Rock10 Posted November 20, 2022 Author Share Posted November 20, 2022 On 11/15/2022 at 10:22 PM, carbking said: Depends on the quality of the rebuild. As the jets are more expensive than Carter, Holley, and Rochester jets, many opt to not replace them. They certainly should be checked for wear; AND NEVER BELIEVE ANYTHING STAMPED ON A JET! Jon How do you measure the jet? Link to comment Share on other sites More sharing options...
Daves1940Buick56S Posted November 20, 2022 Share Posted November 20, 2022 Do you have drill set with numbered drills? If not get one, they are very useful. #70 down to #30. Use the shank end to get the largest smooth (not tight) fit. 1 Link to comment Share on other sites More sharing options...
edinmass Posted November 20, 2022 Share Posted November 20, 2022 (edited) Pin gauges. Cheap and easy. Along this line….. Edited November 20, 2022 by edinmass (see edit history) 3 Link to comment Share on other sites More sharing options...
Bloo Posted November 20, 2022 Share Posted November 20, 2022 I keep a whole set of drills around that have never been used for drilling. A second tiny set takes the smallest from 60 on down to 80. Asking for pin gauges 40+ years ago from the tool dealers got me a bunch of dumb looks and no pin gauges. Now, there they are on Amazon LOL. I'd snap those up if I didn't already have the drills. 1 1 Link to comment Share on other sites More sharing options...
Larry Schramm Posted November 21, 2022 Share Posted November 21, 2022 I have an old pin set that was originally used as a carb adjustment kit from about 1985 and older. I do not use it much any more, but it sure is handy when I do use it. 4 Link to comment Share on other sites More sharing options...
Rock10 Posted November 21, 2022 Author Share Posted November 21, 2022 Well, I need .048" and I don't think they make a bit exactly that size. I have a .043" bit that fits easily in all 4 jets I'm checking. I'm pretty sure they are all the same size and that's what I was looking for. I may check around locally and see if I can find maybe a #56 and #55 bit for a go/no combination. We had thought that someone may had changed the jets at some point before we got the car. They are all stamped .048, but as carbking said, "NEVER BELIEVE ANYTHING STAMPED ON A JET! " Link to comment Share on other sites More sharing options...
edinmass Posted November 21, 2022 Share Posted November 21, 2022 Never believe what is stamped on a jet, or anything that comes out of a politicians mouth! 1 2 Link to comment Share on other sites More sharing options...
Gary W Posted December 7, 2022 Share Posted December 7, 2022 Before I do any damage, can someone please explain how I remove the top of the carburetor (Carter 608S). There is a part in there with a crossbar that is holding up the removal. I have the screws out, but when I lift the top, it only moves about 1/2 an inch when it bottoms out on the "crossbar". How is that part removed so I can lift the top off? Appreciate any help for proper disassembly technique. Thanks! Link to comment Share on other sites More sharing options...
Bloo Posted December 7, 2022 Share Posted December 7, 2022 Wait for @carbking before you do anything rash, but I would probably be spraying penetrating oil in there in the "down" direction. That looks like a Carter WCD, yes? The bar thing lifts the metering rods? And provides for a mechanical override? I think that bar thing is attached to the vacuum piston that controls the metering rods, and it should have just lifted out. The piston might be corroded in place. 2 Link to comment Share on other sites More sharing options...
Larry Schramm Posted December 7, 2022 Share Posted December 7, 2022 Is it a retainer for the needle? 1 Link to comment Share on other sites More sharing options...
Oldtech Posted December 7, 2022 Share Posted December 7, 2022 It is just stuck in the bore. should be a spring in there too. give it some blaster. 2 Link to comment Share on other sites More sharing options...
carbking Posted December 7, 2022 Share Posted December 7, 2022 Bloo and Oldtech are correct about the piston and the spring. The bottom of the metering rod support (the part you are questioning) has an oblong hole. There is a vacuum piston with a horizontal pin that fits into the hole. And there is a vacuum spring under the piston. It is probable that there is corrosion between the brass piston and the zinc alloy casting. Try first: about an hour in an ultrasonic cleaner using a solvant such as Dawn dishwater soap. Run the ultrasonic generator wide open, and run the heaters to about 185 degrees F. If that doesn't work, then place the carburetor in a zip lock bag and place it in your freezer overnight. The next morning, use your favorite flavor of penetrating oil (I don't like any of them, they all stink! ) and spray a good amount down through the top, and also, locate the vacuum source hole for the piston underneath, and spray penetrating oil there. The reason for the freezer is that the coefficient of linear expansion is greater for brass than zinc. A wee amount of free space should open giving the penetrating oil a better chance. PATIENCE IS YOUR BEST FRIEND!!!!! Jon. 4 1 Link to comment Share on other sites More sharing options...
carbking Posted December 7, 2022 Share Posted December 7, 2022 Here is a link to a copy of the original service literature. Carter WCD service literature Note the picture beside instruction number 10 to see the support, link, and spring. DON'T DAMAGE THE CASTING. If the piston, and/or support are not usable, they are available. The spring is in the rebuilding kit. Jon. 1 1 Link to comment Share on other sites More sharing options...
Rock10 Posted December 7, 2022 Author Share Posted December 7, 2022 Just avoid Evapo-rust for now. 👍 1 Link to comment Share on other sites More sharing options...
Gary W Posted December 7, 2022 Share Posted December 7, 2022 Just to clarify.. The part that is holding up removal of the bowl cover is that "T" shaped part. It looks like it has a hole in the bottom that locks with the other part with the pin. Is that correct? So after the freezer, should both those parts lift up as a unit? ALSO: Jon.. Do you have information on "running adjustments"? Specifically, how do I get the automatic choke to open quicker? It takes a full nine to ten minutes to fully open, although when you manually open the choke (during warm up) she wants the extra air. Thank you so much!! I really appreciate it! Gary Link to comment Share on other sites More sharing options...
carbking Posted December 7, 2022 Share Posted December 7, 2022 5 minutes ago, Gary W said: Just to clarify.. The part that is holding up removal of the bowl cover is that "T" shaped part. It looks like it has a hole in the bottom that locks with the other part with the pin. Is that correct? So after the freezer, should both those parts lift up as a unit? ALSO: Jon.. Do you have information on "running adjustments"? Specifically, how do I get the automatic choke to open quicker? It takes a full nine to ten minutes to fully open, although when you manually open the choke (during warm up) she wants the extra air. Yes to lifting together. As to the choke, one of two possible issues: (1) clogged heat tube from heat stove (2) clogged internal vacuum passage supplying vacuum to choke housing Somewhere on this forum I posted how to test with a Kleenex tissue. If you can't find it, call me 573-392-7378 (9-12, 1-4 Mon-Tues central time). Jon. 1 1 Link to comment Share on other sites More sharing options...
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