Bolt Size for Water Neck and Ignition Coil

[73318duster]

I replaced my stock 2bbl carb and intake with a Edelbrock 3776 Intake Manifold and Edelbrock 1405 4bbl carb(pending installation). For some reason the bolts for the water neck and ignition coil do not fit this manifold (3776). I tried them on the old manifold and they go all the way down. I took them to my local auto parts store and was told they were 5/16 bolts and I got both thread sizes and they still do not seem to fit. They said that since its an aftermarket manifold they do not know what bolts I need. Does anyone know the size that I should be looking for?:banghead:

 

[oldkimmer]

...............yes, they should be 5/16......maybe they are metric........if not get a tap and rethread them.......kim.......

 

[BillGrissom]

Doubt they are metric. Probably just corroded threads in the manifold. All you need to cleanup threads is a cheap tap set, especially in aluminum. Get the cheapest one at Harbor Freight. The bolt is probably 5/16 coarse thread. Try the tap, but don't force it too hard or bend it sideways because a broken off tap is not fun. Keep going back and forth with it. I use WD-40 for lube on aluminum. Aluma-tap fluid is better. If the tap goes in fairly easy, that tells you the bolt size. Blow out the holes with air. You are lucky the auto parts guys didn't laugh, since Ace Hardware is a better place for nut & bolt questions. In fact, I would buy stainless bolts there to look purty (I did).

 

[73318duster]

I called Edelbrock apparently I need a 3/8 16 bolt for this. I am going to pick up a kit to rethread if this doesnt work. :violent2:

 

[1Fast340]

just installed my waterneck on a edelbrock airgap manifold and it is 3/8 coarsethread cant remember lenght unfortionaly