Zenith mount holes stripped

mach0415

mach0415

Senior Member
Hello. As we were mounting the freshly rebuilt Zenith 1 to the intake, it was noted that the upper body flange to intake mounting holes have been drilled out. Chalk it up to the fact that this was overlooked upon my rebuilding it.:rolleyes:
So, the questions:

1.) Do we simply mount it with nuts and bolts (originally mounted with bolts that threaded into the carb body)? Its to be a driver. We'll worry about judging standards at some point on that.

2.) Do we weld them shut, drill and retap?

3.) Do we not waste our time and just get another good, used upper body?

4.) Is this a common issue found over the years as people have over/under torqued and stripped out?

Input is appreciated

Mark in NC
 
If the holes were not drilled out to large maybe it will accept a 5/16th helicoil. that would be the way i would try to go. would also loktite the helicoils in
 
I've had this happen on ag equipment over the years... probably the easiest thing to do if you're not worried about fine-point judging, is to use a slightly longer bolt and and nut.

You might have to use a thin jam-nut...

Or the heli-coiol
 
Helicoil crossed my mind, but the hole is waaay too big for stock bolts. Slightly longer bolts with nuts is the way to go for now, I think.
 
You could tap the larger holes to whatever size they will be ,screw in a bolt and lock it with bearing lock, JB Weld or the high strength Locktite. Then cut the bolt off flush and redrill it to standard size.
 
Use a longer bolt with a nut and go have fun driving it. Later you can probably find another intake manifold and fix it right.
 
Because of broken ears, striped out bolt holes for the big bolt etc, there are a lot more good bottoms then tops.
 
I would try the least invasive approach first, i.e., the nut and bolt scenario recommended by several F/B's above. However, looking at the three Zenith 1's I have (one in service and two bench spares) I see only about 1/8" clearance under the forward ear of the carburetor upper body. Thus, absent filing off the underside of this ear, which I would not recommend, you would only get about 1/8 x 18 = 2-1/4 thread engagement on a 1/8"-thick "jamb" nut and 5/16-18 bolt. This might provide marginal bolting force but might be worth a try before going the Heli-coil route. Or, perhaps your Zenith 1 has more clearance under the forward ear.
 
I got a bucket O old carbs in the garage. I got a top I could send you. Its old and rusty in need of restor. As in clean its pasages then re plug it. the treads are good. Not too much play in butterfly shaft. If you want it PM Me.
 
I used to buy Thread-Serts, simple self tapping stainless inserts & no special taps or tools needed to install. Can't locare them anymore. They even had tiny ones to repair stripped holes in pot metal carb bodies. Bill W.
 
Thanks for all the great suggestions. We used larger bolts and nuts to mount it until we get another upper body for it.
 
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