Heating flapper box studs?

[BlueWing]

It is time to replace my flapper boxes that are pretty well shot. I have soaked them for weeks in Kroil but when I tried to see if I can get any movement on a nut I get the sinking feeling the stud will still be attached to the nut in the end. What is behind where the studs are attached? I'm thinking of using my torch with the smallest tip to heat them up and not cause an internal fire.

Next alternative is somehow cut the old flappers to their base and try a dremmel cut off wheel any ideas to cut? Just seems to tight to cleanly use a sawsall.

I just hate to break the factory mounts and use self tappers or tap and bolt them on as my earlier search came up as a work around.

Terry

[Capt J.D.]

Others will jump in, but those "studs" are actuallly welded to that spot from the factory.. at least on my 84 Carrera. There is a thread on cutting them off and rewelding a stud in their place. Perhaps a Dremel, cut off the nuts, and a rethread of the stud may work?
Mine are due up shortly also.

[BlueWing]

Yes the factory does weld them into place. Just got a thought here, I have one of those stud welders for dent pulling and trim stud mounts. Maybe get a copper stud/bolt turn to the stud welder stud size on a lathe, small extension collar for the nose to ground on and quick pull of the trigger. This would "spot weld" a copper stud over the original location. Original fit and appearance with a non corrosive stud for future R&R.

Or just break them, turn slightly sheetmetal screw back on and be done with it.

I just like factory fit and appearance. It is a reflection on care and handling of our cars. Hopefully my car will be around long enough to need a restoration some year.

Terry

[mnez]

I haven't done the flapper boxes, but I've had good success on other small nuts using one of those small butane mini torches, alternately heating, then cooling with penetrant. Only use a box end wrench with light force. If it doesn't work, cutting/splitting the nuts must surely be less work than repairing the snapped of studs.

[j911brick]

Last one I did I cut the nut off with a dremel. The stud was still intact. Use SS nuts when you reinstall.

[vulcan300]

Originally Posted by j911brick

Last one I did I cut the nut off with a dremel. The stud was still intact. Use SS nuts when you reinstall.

What kind of bit did you use on the dremel to cut the nut? It's in an awkward spot and doesn't look easy to cut.

[RWebb]

could cut the nuts with a wheel on a Dremel or use that torch

or bow to the power of oxidation

[j911brick]

Originally Posted by targamaniac

What kind of bit did you use on the dremel to cut the nut? It's in an awkward spot and doesn't look easy to cut.

It was a reinforced cut-off wheel. I think I ended up making several small cuts. Now that I think out it: I cut the heater box off first with a saw so I could access the nut better.

[Tidybuoy]

Just be careful, the driver side is surounded by fuel lines.

On another note: I just replaced my flapper boxes and put thread anti-seize lube on the studs before reassembly.

[D911SC]

If the stud breaks you can drill it out and then tap an M6 thread into it. You can then use an M6 bolt and be done with it.

If you prefer the factory look then you can insert an M6 threaded stud The stud can be welded in place or alternatively you can use a thin nut to secure the stud. The thin nut will hold the stud when you fit the flapper box. No need to torque it up too much if you are using lock nuts. There is enough clearance for the thin nut as the flapper box is raised enough for a thin nut to fit under it. It all seals up nicely with the thick gasket anyway.

An easy way to get an M6 stud is to get a bolt and cut the head off it. The exposed end will rust so put a bit of paint on the tip and insert that end first for a neater finish.

[BlueWing]

Ha ha! raided the wifes work bench.



I always keep worn down cut off wheels for tight spaces such as this, so I swapped hers out for mine and that flexible shaft fit in there.



Now if I can feel my legs and the kinked neck is better by the AM I'll tackle the passenger side.

Really rather fight them that way so when I install the replacements now and in the future it will me just a nut and washer job. I think it is just a matter of do you want to spend time to remove or time to install.

I decided not to use heat as it can disturb any coating on the surface or underneath and promote rust.

Terry

[D911SC]

When you're done, maybe run a thread die over the studs to clean them up. Makes fitting a fresh nut easier and you can reduce the risk of snapping the stud when you reinstall.

I can see why you are removing the flapper boxes!

[RWebb]

wow - those are nasty - don't drive until the rain washes all the salt off the roads (where it kills the fish)

you can buy stainless steel ones, if you are in the upper 1%

don't tell your wife!

[BlueWing]

They are nasty the heat exchangers were just as bad. We have had the car since 04 and never had heat. We only used it well after the salt season ends and before in begins again. I knew the condition when I bought it. The tranny and clutch needed attention so this is part of while I'm in there. Total heater backdate with SSIs. The exhaust hardware came off easier than these, plenty of space with the motor out.

Here is a pick of one of the replacements not yet assembled, Just sprayed them yesterday.

Yes need to chase the threads and antisieze as well.

Terry

[irobertson]

My flapper boxes were shot too. I was able to get all 3 nuts off one side, but after soaking and heating the ones on the other side, I still ended up twisting the studs right off. I ground the remains down, center punched, and drilled them out. Next will be tapping the holes and threading SS bolts in from the back side. Haven't decided how to secure them in place. Might be lock washers, or might be JB Weld. I'm hoping that by going this route I will be able to go back to using nuts. Reason for this is that I don't feel the body metal is thick enough to just bolt into.
We will see how this goes.