348 Advice needed: broken coolant bung

I was changing the oil on my '90 348 and while changing the oil filter I noticed a bulge on the coolant hose that runs from the overflow tank to the aluminum cross member. It was where it attaches to the aluminum cross member between the heads below the intake runners. I pushed on the hose and coolant was leaking. There was quite a bit of corrosion so it had been seeping for some time. One gentle twist on the clamp and the aluminum bung snapped off at its base. I have several questions and am open to recommendations.
1) Obviously cannot remove the cross member without removing one or both sides of the intake runners. Can it be done removing just one side, and if so, which one?
2) Can it be addressed without removing the runners? Possibly drill, tap and thread in a bung while in place. I do have a straight shot at the broken bung.
Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login

 

I did a brief search and realized it’s common but haven’t found the repair thread. I’ll keep searching. Thanks.

 

Thank you all for the input. I plan on starting the repair this week. I didn’t know it was threaded piece so replacing without removing would be impossible with all the corrosion. I’ll post updates w/ pics. I’ve had the car since 2018 and this will be the first significant mechanical job. It’s well within my wheelhouse but I’m sure to have a question or two.

 

Well the disassembly went fairly smooth. The only casualty was one of the allen bolts securing the fuel rail. Luckily it was
one of the accessible ones. Soaked it with D-40, still stripped. Tried a 12mm socket around the outside, stripped that. Gently hammered in
a 7 mm and stripped that also. Therefore I just used a 5/16 drill bit, just a little bigger than the shaft of the bolt and drilled off the head. I used a magnet to collect the metal shavings, then vacuumed and the compressed air to clean the area. I didn't want any shavings to fall into the open intake ports on the head Now I can deal with the remaining stud on the work bench. Maybe attempt an easyout or just drill it out and tap it for a larger bolt.
The only other casualty was a plastic clamp holding the flexible fuel line to a valve cover stud.

I haven't decided on a solution for the corroded bung. If I can get it out and preserve the original threads I will order the Hill Engineering stainless
piece. If the threads are damaged by corrosion (or by me) I'll opt for a brass bung with larger thread diameter.

The whole job took and hour and 45 min. Next will be about 6 hours of cleaning, polishing and maybe black crinkle coat the plenum? Replace some vacuum hoses and what ever else looks questionable.

Also may send out the injectors for a good cleaning.

The gasket for the runners is in good shape. reuse or replace?




Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login

 

@AceMaster - I have some of those from a previous Alfa restoration, thanks for reminding me!

@fatbillybob - The intake broken bolt came out after soaking with WD 40 and a simple twist with Vicegrips. The water housing lower sensor has some type of white sealer and I couldn't break it loose. It has a plastic housing so I didn't want to apply heat. Also the remaining nub was small and thin. I say "was" because I got it out using increasing size drill bits until I saw some threads. Then started with a 10 X 1.50mm tap then 11mm then 12 mm and all the threads look good.

And before I go any further, I wanted to thank Ferrarium for attaching the link to Ernie's thread with detailed instructions and pic of the plenum removal.
It probably saved me at least 2 additional hours. I would like to think I would have eventually figured it out but would have removed too much or too little and
broke more ****!
More to come.....