Screw size for Thermstat Cover

[thefirebirdman]

You guys are going to think I'm crazy but I've been searching here and the internet for 30min looking for a reference for the screw size for the 3 screws that attach the choke to the choke housing. I have an Edelbrock 1904 which had the choke riveted on. I drilled them out in the event I need to replace the electronic choke. I couldn't find any reference to the screw size for these screws in Cliff's book either. Appreciate the help.

[Ethan1]

You guys are going to think I'm crazy but I've been searching here and the internet for 30min looking for a reference for the screw size for the 3 screws that attach the choke to the choke housing. I have an Edelbrock 1904 which had the choke riveted on. I drilled them out in the event I need to replace the electronic choke. I couldn't find any reference to the screw size for these screws in Cliff's book either. Appreciate the help.

 I believe they are 8-32x5/16". Wouldn't hurt to try. Also, I believe you will need self-tapping screws as well.

[Ethan1]

 By the way, Welcome to CHP.

[thefirebirdman]

Thanks Ethan. I was so frustrated. I will give it a shot. I have a correct Cliff prep'd Q-Jet on my '73 Trans Am and it runs great. Had to wait about 6 months to get it through the process but it was worth it. Now I'm trying to learn to do them myself.

[429bbf]

firebird i dont like to use self tapping screws to many carbs i get are messed up and half stripped out. i like to tap the hole first and then install a screw.i think i tapped the last one to 8-24 you just have to see what works good.

[Ethan1]

firebird i dont like to use self tapping screws to many carbs i get are messed up and half stripped out. i like to tap the hole first and then install a screw.i think i tapped the last one to 8-24 you just have to see what works good.

 I measured all mine. 8-32. Doesn't really matter on threads being coarser anyways.....

[thefirebirdman]

Thanks all. Appreciate the feedback. Such a simple thing, most people didn't think to post anything about I'm sure. Or most have chokes with screws already provided.

[Ethan1]

Thanks all. Appreciate the feedback. Such a simple thing, most people didn't think to post anything about I'm sure. Or most have chokes with screws already provided.

 Yeah, most of the ones I have seen have the screws provided. I also agree with 429bbf, tapping the holes yourself would probably be the best way to go. Probably be much easier than using self-tapping screws.

[429bbf]

one more subject of interest. your choke housing may have a little aluminum piece protruding in at the 3 oclock screw. if you buy the GOOD choke coil it will line up with the notch . if not you will have to grind (i use a small cutoff wheel )to grind it out . if not you will not be able to rotate the coil to get the choke adjusted properly . cliff sells a good coil.

[Cliff Ruggles]

Through 1978 the thread size will be #8-32 with fillister heads.

The riveted choke housings can be tapped for #10 threads.  I prefer 10-32's with fillister heads vs the self tapping variety.

If you have a choke housing that has the square "notch" it will need to be removed to provide full adjustment of the choke once the carb is placed in service.  The material is easily removed by hitting it with a small flat punch before installing the choke coil.....Cliff