Tweet
I have ordered phillips head choke coil screws for my 1971 454/ 4 speed coupe from many different vendors and none are correct. They are all too small. The current hold down fastener is a bolt that is the same size/similar as a valve cover bolt. The manifold is date correct and I have no reason to believe it is not the original manifold. The car was judged in 2003 and took a deduction for not having a phillips screw. I have no idea what to do. Can I be the only one with this issue? I hate to lose points for a such an easy fix. Any help/suggestions would be appreciated..Jim
-
-
Re: 1971 Choke coil screw
Just curious Jim, how many points were deducted for the choke coil screw? -
Re: 1971 Choke coil screw
Jim
The bolts holding down the valve cover are 1/4- 20 and the choke coil is 10-24 so at sometime it must have stripped out and the fix was a larger thread size.
Their are many ways to fix this condition and return the hole to the size of the screws you have bought. Check the screw you have for size before working on the manifold.
LyleLyle
Comment
-
Re: 1971 Choke coil screw
Jim-----
If the screw is, indeed, a 1/4"-20 or 1/4"-28, then it's not original to the car. At least, it's not original unless it was some sort of a factory repair. That's a possibility, but it would be hard to document. Certainly, a 1/4" screw "would not be typical of factory production".
The only screw that I have ever seen used for this application is a phillips head, 10-24 thread size.In Appreciation of John HinckleyComment
-
Re: 1971 Choke coil screw
Jim,
You could use an E-Z lok thread insert to bring the hole back to a 10-24 thread size. The standard insert has a 10-24 internal thread and a 3/8-16 external thread. This of course means tapping the hole for the 3/8-16 thread. I'm not familiar with your manifold so check to see if there is enough metal for that size thread. If there isn't they also make a thin wall insert with a 10-24 int. thrd. and a 5/16-18 external thread. Hope this helps.Comment
-
Re: 1971 Choke coil screw
Erich----
The configuration of the 71 intake manifold choke pad is such that it could easily accomodate any of the thread repairs you mentioned. It would be no problem, at all.In Appreciation of John HinckleyComment
-
Re: 1971 Choke coil screw
Joe
The one problem is there is very little depth of metal where the screw is so be carefull. I found this out the hard way and as I recall less than 1/2" thick on the manifold I was working on.
LyleLyle
Comment
-
Re: 1971 Choke coil screw
Lyle-----
Yes, one does not want to drill deeper than the original hole. However, what I was referring to is the fact that there is plenty of peripheral material for the oversize drilling necessary for a thread repair device.
Actually, I don't really see where drilling through would cause much of a problem. The screw would "seal the hole".In Appreciation of John HinckleyComment
Comment