Can you poke through it with a screwdriver?

 

Fiberglass has no place in this repair.

If it's structurally sound (the screwdriver test as above), then you can use a rust converter on it. (Por15 makes a good one; there are others too.)

If it's not structurally sound (a screwdriver can be jammed through it), cut out the bad metal and weld in new, even if you have to pay a body guy to do it. Patch panels are readily available.

 

It looks like there are some pinholes going completely through in the pics. I would get some new pans for it if it were me. The hole in the floor is just a drain hole and I doubt that the rust originated from there, water usually comes from above not below. You probably have a leaking windshield/ back glass or cowl.

 

X2 - looks like pin holes in the one photo and the appearance of the metal in the close up looks very rusted. I think you need new floor pans also. You can probably fix it temporarily with POR-15 products (they make an epoxy for filling holes also) but at some point you'll have to bite the bullet.

PS - the big hole is a factory stamped drain hole that comes with a matching plate. It actually looks pretty sealed up in the picture. You might want to remove more of the carpet and see if the front section is also rusted - usually this come from cowel panel rot.

 

No need for the screwdriver, there are visible signs of holes in the floor:

http://i643.photobucket.com/albums/uu153/DPTodd/DSC00451.jpg

"I have access to a welding machine, but I and the owner do not know how to weld. It was his son's, and his son moved North."

Welding is not something you just. 'do'. I mean you can do it, but it takes practice and actually becomes an art. I know guys that actually work at body shops, that don't really know how to weld... Yet its their job.

You cutting something out and replacing could actually allow more water in, then the few holes you presently have. Buy the sheetmetal and have some pros do it. Please I am beggin ya...

Peace of mind...

Snell

 

Yeah I need new floor panels UGH this is such a setback.

 

Kinda looks like the pans have been replaced before.

 

This has cowl problems written all over it.

Before you start with the floor, start by inspecting the cowl, firewall and windshield. You can fix the floor, but if you don't find the root cause, you're doing it again in 5-10 years

 

Kinda looks like the pans have been replaced before.

Yep exactly... so now I would take flashlight and crawl under dash and be looking at that cowl...

You are getting some continuous water from somewhere.

Snell

 

I dont know, i can see a few other areas that are suspect.

Missing drain hole cover
http://i643.photobucket.com/albums/uu153/DPTodd/DSC00450.jpg

Hole in DS floor pan
http://i643.photobucket.com/albums/uu153/DPTodd/DSC00452.jpg

Looks like rear drain hole just has sealant and no plug in the hole.
http://i643.photobucket.com/albums/uu153/DPTodd/DSC00457.jpg

 

I agree... it looks like someone has already replaced some of the metal.

As others suggest, it is time to fill a bucket with water and pour it into the cowl opening. Chances are that water did not come up from below.

As far as replacing the floor pans yourself, I have personally done this and it is a great first welding project. Modern MIG welding with shielding gas is fairly easy to pick up by reading, watching online videos, and practicing on scrap metal. I would not be afraid of replacing the floor pans... it is trivial to inspect weld penetration on thin sheet metal with access to both sides.

If the cowl is leaking (as I and others suspect), this is a more involved repair but not beyond the reach of a beginner. Lots of spot welds to drill out for access and a royal PITA though. And I would be tempted to do the floors first to gain a bit more feel for weld penetration since you may not have access to visualy inspect both sides of your plug welds.

There are areas and types of repairs that I would not recommend for a beginner due to structural integrity issues for poor welds and implications of collision damage; but rusted floor boards are not something to be afraid of as a beginning welder.

Good luck,
-Rory

 

I took that drainhole cover off. The one that appears to be sealed...I have no idea what the hell it is. The hole was there. If I have cowl problems, can I just sit in the car and have someone spray it with a hose and easily see the leak, or will I have to really look for it?

Thanks for all your help.

EDIT: Removed some more insulation, then found this hole directly under the heater box, very close to where the passenger's side kick panel is:

 

I like to test the cowl seperately from the windshield.

You do not need to be in the car at all.

1) Start with a dry floor pan.
2) pour a bucket of water in the cowl opening
3) look to see if your floor pan is still dry
4) if not, your cowl is leaking...
5) if your floor pan is still dry, hit the windshield with a hose for a few minutes...
6) check the floor pan again.

If your cowl or windshield are leaking, to fix it correctly you will have to disassemble and assess the true extent of the situation.

As a rule of thumb, the extent of the rust damage is far worse than what is visible. (e.g. those pinholes you have will turn into quarter size holes if you media blast and remove all the bad metal).

Good luck,
-Rory

 

looks like shotty repair work to me at some point

 

As far as replacing the floor pans yourself, I have personally done this and it is a great first welding project. Modern MIG welding with shielding gas is fairly easy to pick up by reading, watching online videos, and practicing on scrap metal. I would not be afraid of replacing the floor pans... it is trivial to inspect weld penetration on thin sheet metal with access to both sides.

I definitely dont want to step on 2nds' toes here, but putting the pans in is not JUST putting the pans in... The pans not only shield interior from water but are a key component to making your car structurally sound, and if not laid correctly can really screw up the alignment of a unibody car. Roof, tunnel and rockers are not enough to keep that car solid.

Considering the cost. I still would hire out, and look over the guys shoulder as he cuts one side out at a time and ideally has X Supports webbing the door frames.

Snell

 

Re: ust in the floorboards

EDIT: Removed some more insulation, then found this hole directly under the heater box, very close to where the passenger's side kick panel is:

Well hopefully this is the good news... That would be a direct shot of water coming off tires and into that crack... I can see tons of water coming in there that way...

Hopefully this is it and cowl is fine...


Snell

 

It could also have had a leaking heater core in the past.

Frank

 

Your passenger and driver front floor pans look to have been replaced in the past, there is a seam weld along the tunnel which gives it away. Someone may have tried to fix it without addressing the underlying problem (cowl?) and it rusted out again.

As far as repairing, the question to me is whether you have a coupe or a convertible. The coupe roof ties the structure together, and I believe could allow you to tackle this on your own while learning something new along the way. I learned to MIG weld on my coupes floor pans, the carpet will cover your "learnings." If its a convertible, considerable bracing is required and might be worth farming out.

If you do it yourself, be sure to get the floor plans with the rocker tabs bent upwards, the ones I had from NPD were the wrong way and I had to manually flange it and bend it the other way. Throw a passenger torque box in there while you're at it and you will be all set.

Just my thoughts.

 

I've never seen floor pans rust due to water coming from the wheelwell.

It is/was either the cowl/windshield/heater core that caused the initial problem.

Sometimes the windshield leaks run behind the kick panels. Very sneaky.

 

I have a coupe. However, I've been getting two different answers! Hire out or do it yourself...I can see the problems with doing it myself, and I don't think I would feel comfortable doing it myself. Thanks for all the ideas. I have to go do some yard work for a friend and then I'll have the day to figure out where the water is coming from.

Thanks.

 

I'm in the do-it-yourself camp IF you have the time, the space, and the right tools.

You'll save yourself a ton of money. Plus, you'll know that it was done right (provided that you do your research), you'll pick up a new skill, and you'll have the personal satisfaction of completing the job.

 

I definitely dont want to step on 2nds' toes here, but putting the pans in is not JUST putting the pans in... The pans not only shield interior from water but are a key component to making your car structurally sound, and if not laid correctly can really screw up the alignment of a unibody car. Roof, tunnel and rockers are not enough to keep that car solid.

Considering the cost. I still would hire out, and look over the guys shoulder as he cuts one side out at a time and ideally has X Supports webbing the door frames.

Snell

No toes stepped on! The biggest indicator here to me is that the OP does not seem to want to take this on, in which case he should by all means hire it out.

We will have to "agree to disagree" on floor pan replacement on a coupe/fastback. I have seen this done many times at restoration shops and have NEVER seen door bracing used for floor pan replacement on anything but a convertable or a car where the subframe/rockers were rusted out and being replaced too. I did a lot of research, talked with body men, and watched several replacements before attempting this myself.

The foor pan IS a part of the unibody and does contribute to the structural integrity of the car, but once again the key to welding is penetration of the weld. As to the alignment concern, if his subframes, roof, and rockers are not sufficient to hold with a floor pan removed, then given how compromised his floor pans already are he would already have a problem... My floor pan looked better than his, and when I media blasted it it looked like swiss cheese! Finally, recall that the FACTORY specification for these car bodies had tolerances of +/- 1/4 inch!

We all have limits on what we are willing and able to take on with these cars. For me I would never take on major structural repair, finish bodywork and painting. I, and several others on this forum have taken on floor pan replacement as our first welding project (in my case due to the encouragement of members on this very site!). That said, when my car was on the rotisserrie being painted, the body and paint professionals said the floor pan replacement was as good or better than a professional job. I may not be the best welder, but I was willing to take the time and grind down the butt welds to make the repair virtually invisible. Can you see the driver's side full floor pan was replaced?

http://forums.vintage-mustang.com/files/attachments/1190580383-Primered.jpg
http://forums.vintage-mustang.com/files/attachments/1190580454-front_clamped.jpg
http://forums.vintage-mustang.com/files/attachments/1190580587-Rear_clamped.jpg
http://forums.vintage-mustang.com/files/attachments/1192418441-IMG_3741__Small_.JPG
http://forums.vintage-mustang.com/files/attachments/1192418522-IMG_3742__Small_.JPG

http://forums.vintage-mustang.com/files/attachments/1237218766-seam_sealed.JPG

BTW - the sub frame connectors were NOT installed when I replaced the floor pan.

Good luck,
-Rory

 

Re: ust in the floorboards

I've never seen floor pans rust due to water coming from the wheelwell.

It is/was either the cowl/windshield/heater core that caused the initial problem.

Sometimes the windshield leaks run behind the kick panels. Very sneaky.

Agreed, but given that both floor pans are shot it is doubtful that the heater is the only culprit. My last comment on this post (I promise!) is that the last pictures the OP posted indicate to me that he needs to replace/patch the toe board(s) in addition to the floor pan (unless his year is significantly different from a 69).

-Rory

 

Re: ust in the floorboards

Can floorpans be replaced while the car is on a rotisserie?

 

No worries about your posts 2nd gen! Thats why you are here is to help! Now, you are telling me that I DON'T need bracing? This is a 1968 2dr Coupe 289. The frame looks good, I'll have to check it out today when I pull it out. I'm going to go check where the leak is coming from RIGHT now. Be back in a few.

Thanks for all the help!