Threaded piece for wooden floorboard is broken...

[fallingat120mph]

86 Coupe and the below photo is what is broken:




It's the threaded part that holds the wooden floorboard down around my pedals. It has been unusable since I bought the car and am looking for a fix or fix ideas.

Was hoping it was a coated (undercoating) hex or screw head but doesn't seem like there is a way to remove or fix without cleaning the area in the cabin and welding a new threaded portion in.

Just wondering how others have dealt with this issue.

EDIT: Sorry if I missed a thread already established...couldn't find any info.

Thanks,
Erik

[digitaldgp]

I had the same issue on my 1970 911.

I took vice grips and broke off the remaining stub flush, then I drilled it out through the floorpan.

Then you can JB weld in a new M6x20 bolt to pass through the pan into floor board and put a nut on it.

Also I used Zinc plated fasteners.

Pretty simple repair.

[fallingat120mph]

Originally Posted by digitaldgp

I had the same issue on my 1970 911.

I took vice grips and broke off the remaining stub flush, then I drilled it out through the floorpan.

Then you can JB weld in a new M6x20 bolt to pass through the pan into floor board and put a nut on it.

Also I used Zinc plated fasteners.

Pretty simple repair.

Good to hear. Was under it again today and thinking the same thing after looking at it. Hearing your success story may have pointed me in the right direction.

Thanks for the response!
Erik

[thetorch]

I wouldn't do JB weld. Just drill it out and put in a zinc-plated M6 rivnut and a bolt.

[Dpmulvan]

[digitaldgp]

Originally Posted by thetorch

I wouldn't do JB weld. Just drill it out and put in a zinc-plated M6 rivnut and a bolt.

JB weld was just to seal and hold the bolt until final installation of the nut. Then spray the underside with undercoating.

[HarryD]

I drilled my broken stud out, tapped new threads and put a bolt there. More time was spent at the hardware store than the repair itself.

[fallingat120mph]

Originally Posted by HarryD

I drilled my broken stud out, tapped new threads and put a bolt there. More time was spent at the hardware store than the repair itself.

Indeed.

I forgot I had a tap and die set - and found last it last night. So, plans have changed and may go that route.


Thanks HarryD - yet another option.



Thanks everyone for the input. It seems in this case the "keep it simple" saying goes a long way. Dropping/swapping engines and correcting previous owners mistakes has me overthinking even the most simple "fixes".

Floor boards are in great shape and want to keep them that way, but it also is a daily/weekly driver so not a show car.


Thanks everyone - appreciate it the input.

Erik

[PeteKz]

If the floor boards are in great shape, preserve what you have by coating them several times in clear polyurethane. Make sure it soaks thoroughly into the edges. Those will absorb a lot of polyurethane. You want them completely sealed against moisture.

[fallingat120mph]

Originally Posted by PeteKz

If the floor boards are in great shape, preserve what you have by coating them several times in clear polyurethane. Make sure it soaks thoroughly into the edges. Those will absorb a lot of polyurethane. You want them completely sealed against moisture.

They are oddly shiny - was thinking the previous owner may have done similar.

Yes, seeing how much replacements are (that are new or in this good of shape) I will try and take care of the best I can.

Thanks!
Erik

[EC900]

If you can’t weld a new stud anytime soon, you might find one of these “threaded coupler” nuts (below) can work if there’s enough tread remaining to bring up the height. I couldn’t find any metric sizes but they sure be available somewhere. I know furniture connectors can be had in M6 size.

As for the floorboard itself, my driver side was in poor shape, faded out color with the plywood separating from just general wear and perhaps moisture from wet shoes. I opened the delaminated plywood, filled it the separations with wood glue, clamped, light sanding and re-stained both driver/pass sides in Miniwax black, then polyurethane with a satin finish. Looks like new.

[fallingat120mph]

Originally Posted by EC900

If you can’t weld a new stud anytime soon, you might find one of these “threaded coupler” nuts (below) can work if there’s enough tread remaining to bring up the height. I couldn’t find any metric sizes but they sure be available somewhere. I know furniture connectors can be had in M6 size.

As for the floorboard itself, my driver side was in poor shape, faded out color with the plywood separating from just general wear and perhaps moisture from wet shoes. I opened the delaminated plywood, filled it the separations with wood glue, clamped, light sanding and re-stained both driver/pass sides in Miniwax black, then polyurethane with a satin finish. Looks like new.

Great info on both accounts. At this point have enough info/ideas to fix the stud and treat the floorboard.

What started as a fix for me hopefully can help others in future searches. Great info from all...


Thanks and ready to start tackling the "projects".




Again, thank you to all who have posted in this thread-
Erik

[fallingat120mph]

Originally Posted by HarryD

I drilled my broken stud out, tapped new threads and put a bolt there. More time was spent at the hardware store than the repair itself.

This is the method I went with.

Picked up some M6x20 bolts online, tapped new threads and turned out great.

Need to clean up and get the undercoating taken care of, but really happy.

Thanks to everyone for the responses.

Erik

[GH85Carrera]

Put a little antiseize on the threads before you tighten the nut. The water from passengers feet get that area wet if you drive in the rain. All road-going Porsches came with windshield wipers right from the factory. I have driven in the rain many times.

[fallingat120mph]

Originally Posted by GH85Carrera

Put a little antiseize on the threads before you tighten the nut. The water from passengers feet get that area wet if you drive in the rain. All road-going Porsches came with windshield wipers right from the factory. I have driven in the rain many times.

Yes, I drive in the rain and winter months and agree. Am also going to do better with the new carpets and mats and remove to let moisture dry out after wet conditions. Seems the previous owner let a lot of moisture sit after driving and my previous floorboard nuts were pretty corroded.

Also, like others have stated may treat the floorboards to protect from aging and moisture.


Erik

[EC900]

@fallingat120mph, for what it’s worth concerning the floorboards…
It’s amazing how much water can get I trapped under the mats from wet shoes over 45 years…even in SoCal. I don’t drive in Midwest winter or rain if possible. But a floor fan is always on in my garage.

I refurbed my floorboards which had the plywood beginning to separate from excessive moisture.
I used some TiteBond exterior grade wood glue, getting deep into the plywood separations particularly at the bottom ends notoriously prone to damage, be sure to clamp it all around and let it set for a few days. Then lightly sanded the old faded color and any excess glue. Not sure what color the floorboards were originally but looked bluish-black, so I used Varathane ebony black stain, then once dry sealed with a satin clear lacquer or satin polyurethane, can’t recall though lacquers dry quick and tad better imo for sealing moisture in multiple coats without waiting days to poly to dry, re-sand and repeat for multi coats.
The black and clearcoat came out nice -like new- for something that’s hidden under the carpets, unfortunately I don’t have a pic of the before/aft results.

[fallingat120mph]

Originally Posted by EC900

@fallingat120mph, for what it’s worth concerning the floorboards…
It’s amazing how much water can get I trapped under the mats from wet shoes over 45 years…even in SoCal. I don’t drive in Midwest winter or rain if possible. But a floor fan is always on in my garage.

I refurbed my floorboards which had the plywood beginning to separate from excessive moisture.
I used some TiteBond exterior grade wood glue, getting deep into the plywood separations particularly at the bottom ends notoriously prone to damage, be sure to clamp it all around and let it set for a few days. Then lightly sanded the old faded color and any excess glue. Not sure what color the floorboards were originally but looked bluish-black, so I used Varathane ebony black stain, then once dry sealed with a satin clear lacquer or satin polyurethane, can’t recall though lacquers dry quick and tad better imo for sealing moisture in multiple coats without waiting days to poly to dry, re-sand and repeat for multi coats.
The black and clearcoat came out nice -like new- for something that’s hidden under the carpets, unfortunately I don’t have a pic of the before/aft results.

Excellent response.

Hopefully this can help others who search out this information in the future.

Thanks!
Erik