Fixing a hole in TB butterfly

[Drifty Midship]

Got this TB off a mate.
Geniuses who had put it on his car drilled a hole in the butterfly apparently to get it to idle.
You can see the hole in the pic below...
I've chucked it on my car but idle is sitting high at about 1500...
I've tweaked fuel and timing in my ecu to bring it back to 1350.
There is no idle screw or any other types of bypass on the TB.
So my question is what can I use that will be safe to plug up the hole in the butterfly... obviously what ever i put there i don't want to fall out cause next stop is the supercharger...
Or if anyone knows where i can get another butterfly as a replacement...

[Duk]

Bolt, nut a washer either side of the butterfly valve and high strength loctite on the thread.
Or get another butterfly valve.

[ill-minded]

solder a thin sheet of brass over it? or even just fill the hole with solder? so long as inlet temps aren't hot enough to weaken/melt the solder, everything should be dandy, no?

otherwise, as above. not an ideal solution for airflow, but would solve the problem.

[omp]

For fear of sounding like a freak, how about a pop rivet?

[Mr Ed]

Pull it out, weld it up, grind it flat. Dont put a bolt/rivet through it FFS, theres a reason theyre milled to a nice flat surface.

[jonathan yee]

what TB is it? size? if it's 65mm then chances are a ford butterfly will fit. form any of their 4L 6cyl motors.

[lexsmaz]

I second the remove & weld, brazing it should work well ..

[Drifty Midship]

thanks for the input...
Think I will go for the braze option.
Other ideas I had was metal mend or fibreglass or was thinking solder also.
TB is 70mm

[RobertoX]

Best choice is to fill in properly with weld but if you were going to use a screw/bolt, tap the hole, screw it in with loctite and then stake the end on the bottom of the bolt with a chisel so it can't physically be unscrewed (like how they do with the bolts holding the plate to the throttle shaft)
I've had a one of the shaft bolts come out and rattle around one of the cylinders for a bit, not nice for the motor :/

Anyway, it looks like you went for the right choice in the end

[MWP]

Solder it up.
Normal soft electronics solder would do the job, doesnt need to be strong.

[pandaah]

i wouldnt put too much heat into it, there not that strong of a metal and even if it goes out of shape slightly it wont seal in the throttle body anymore...

bolt and nut with a nyloc nut will do the job perfect, no mess, no heat.. perfect

[ill-minded]

also, if you're gonna solder it, i'd grab a countersink bit (or even a larger drill bit) and just run a chamfer around the edge so the solder would form a lip over the edge of the hole for extra reassurance that it doesn't become dislodged and get eaten by the engine.

[andrew_mx83]

+3 for brazing

i wouldnt trust solder...

[oldcorollas]

Pull it out, weld it up, grind it flat. Dont put a bolt/rivet through it FFS, theres a reason theyre milled to a nice flat surface.

LOL at weld....
milled? they are cut from sheet...

back from holiday eh ed? or is it school holidays?

[william]

Araldite maybe?