Notices
1973 - 1979 F-100 & Larger F-Series Trucks Discuss the Dentsides Ford Truck
Sponsored by:
Sponsored by: Moser

Rusted Floor Pan.

Thread Tools
 
Search this Thread
 
Old Aug 1, 2012 | 12:15 AM
  #1  
fasthauler's Avatar
fasthauler
Thread Starter
|
Fleet Mechanic
20 Year Member
Joined: Mar 2004
Posts: 1,398
Likes: 17
From: Hesperia, CA
Club FTE Gold Member
Rusted Floor Pan.

I pulled the old floor mat and found this under the drivers side floor pan. It is a section about 6 by 12 inches and the paint on the underside of the cab is still intact with no rust showing. The rest of the floor pan looks to be in pretty good shape. This area appears to still be structurally sound. I was thinking of filling in the pinholes with JB Weld or possibly Bondo and then repainting the area. I am looking for suggestions from others that have had this problem.
 
Attached Images  
Reply
Old Aug 1, 2012 | 12:19 AM
  #2  
devino246's Avatar
devino246
Post Fiend
Joined: Mar 2011
Posts: 8,501
Likes: 4
From: Lynchburg, VA
Well the proper fix would be to cut out the section and weld in new metal, but most people don't have access to a welder. For a quick fix, I'd run some seamsealer over both sides of the holes, let it dry, and then go over that with undercoating.
 
Reply
Old Aug 1, 2012 | 12:55 AM
  #3  
gpence's Avatar
gpence
Elder User
Joined: Oct 2011
Posts: 842
Likes: 0
From: Palmyra
that dont look to bad. It looks like it's a flat area just make a patch out of a junk hood or something & weld it in their or just weld up the holes and grind the welds back down.
 
Reply
Old Aug 1, 2012 | 09:54 AM
  #4  
bertha66's Avatar
bertha66
Lead Driver
20 Year Member
Liked
Loved
Community Favorite
Joined: Oct 2004
Posts: 8,062
Likes: 35
From: Central Oregon
Di you know where the water is coming from? Before you fix, fine out what is the cause of the rust, so you do not have to do it over again.
 
Reply
Old Aug 1, 2012 | 11:15 AM
  #5  
arctic y block's Avatar
arctic y block
Post Fiend
Joined: Sep 2006
Posts: 14,325
Likes: 14
From: Island Southeast Alaska
If ya heat the metal red hot with like a propane bottle torch it will kill the rust. Than seal and bondo it. Careful not to warp it.

Or just spray with Ospho available at any hardware or parts store. Marine store as well. After it drys and turns black with a dusting of white powder just clean and paint it.
 
Reply
Old Aug 5, 2012 | 10:07 AM
  #6  
fasthauler's Avatar
fasthauler
Thread Starter
|
Fleet Mechanic
20 Year Member
Joined: Mar 2004
Posts: 1,398
Likes: 17
From: Hesperia, CA
Club FTE Gold Member
I had never heard of Ospho, so I did some research on the stuff on the Internet and it looks very promising. Since the area seems structurally sound and I don’t have access to welding equipment I think I will go this route with the Bondo after the Ospho treatment. Thank for all of the information guys.
 
Reply
Old Aug 5, 2012 | 12:15 PM
  #7  
crazy96863's Avatar
crazy96863
Cargo Master
15 Year Member
Photogenic
Photoriffic
Liked
Joined: May 2011
Posts: 2,388
Likes: 138
From: Northern California
POR15... I recommend it. Research it and decide for yourself. I coated my entire floor with it.

This is what I started w/:





Stripped the entire floor after patches welded in:



Finished product:



I an pretty happy with this. My only advise is to strictly follow the directions. The rest of my truck will end up a pile of rust but my cab floor will still be sitting there on the ground.
 
Reply
Old Aug 5, 2012 | 03:00 PM
  #8  
Rossta86's Avatar
Rossta86
Senior User
20 Year Member
Joined: Aug 2005
Posts: 183
Likes: 1
I would strongly discourage the use of a Polyester body filler such as bondo for this application. If you don't have the use of a welder i would recommend panel adhesive with a metal patch, fiberglass filler, or even seam sealer to fill pin holes as mentioned by devino246 after removing all of the rust.

Sandblasting the rusted area is in my opinion the best rust removal method, but if you use a product containing phosphoric acid such as Ospho i would recommend rinsing the area well with water after use (counter intuitive i know) before painting or applying any type of filler. I know the Ospho directions claim you do not need to neutralize, but there are some horror stories out there depending on the topcoat used. Some coatings will have no issues though.

Like bertha66 said, find where the moisture is coming from; windshield seal, firewall grommets, door seals are a few ideas.....

These are just my opinions as there are a lot of ways out there to tackle rust, but I think we can all agree that unless you remove all the rust and completely seal the area from moisture, the rust will be back.
 
Reply
FTE Stories

Ford Trucks for Ford Truck Enthusiasts

story-0

10 Ways Ford is LOSING to the Competition

 Joe Kucinski
story-1

Top 6 Best Deals Available on New Fords & Lincolns Right Now

 Brett Foote
story-2

This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level

 Verdad Gallardo
story-3

Top 10 Fords at 2026 Carlisle Ford Nationals

 Joe Kucinski
story-4

3 Best / 3 Worst Parts of Modern Ford Ownership

 Brett Foote
story-5

10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches

 Pouria Savadkouei
story-6

Every 2026 Ford Engine Explained

 Brett Foote
story-7

10 Ugly Ford Trucks That We Still Kinda Love

 Joe Kucinski
story-8

10 Things Every Truck Owner NEEDS (2026 Edition)

 Michael S. Palmer
story-9

Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath

 Verdad Gallardo
Old Aug 5, 2012 | 03:22 PM
  #9  
HIO Silver's Avatar
HIO Silver
Fleet Owner
Joined: Dec 2009
Posts: 20,678
Likes: 83
From: NorCal
FYI: Phosphoric acid

A inexpensive source for phosphoric acid is Concrete Etcher from Home Depot... about $13 a gallon.
 
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
BiltFordTuff
1973 - 1979 F-100 & Larger F-Series Trucks
1
Apr 14, 2011 01:49 PM
oldtexasdog
1967 - 1972 F-100 & Larger F-Series Trucks
6
Mar 30, 2009 10:56 AM
76 F150 Ranger XLT
1973 - 1979 F-100 & Larger F-Series Trucks
9
Apr 24, 2005 10:26 AM
murphydo
Paint & Bodywork
2
Nov 4, 2001 11:55 AM
lee
Paint & Bodywork
5
Jul 16, 2001 08:47 AM




All times are GMT -5. The time now is 07:45 AM.

story-0
10 Ways Ford is LOSING to the Competition

Slideshow: 10 ways Ford is losing to the competition

By Joe Kucinski | 2026-06-15 09:52:01


VIEW MORE
story-1
Top 6 Best Deals Available on New Fords & Lincolns Right Now

Some great targets in today's expensive world.

By Brett Foote | 2026-06-15 09:35:19


VIEW MORE
story-2
This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level

Slideshow: The VelociRaptor Expedition gains a lift, upgraded suspension, Brembo brakes, and trail-ready equipment while retaining the stock 440-horsepower EcoBoost V6.

By Verdad Gallardo | 2026-06-12 11:01:55


VIEW MORE
story-3
Top 10 Fords at 2026 Carlisle Ford Nationals

Slideshow: Top 10 Fords at 2026 Ford Nationals

By Joe Kucinski | 2026-06-09 11:10:08


VIEW MORE
story-4
3 Best / 3 Worst Parts of Modern Ford Ownership

Based on years of owning multiple modern Ford products.

By Brett Foote | 2026-06-09 10:53:36


VIEW MORE
story-5
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches

SPONSORED: From muddy boots to rain-soaked cargo, these upgrades address some of the most common frustrations Ford truck owners face every day.

By Pouria Savadkouei | 2026-06-08 18:50:34


VIEW MORE
story-6
Every 2026 Ford Engine Explained

Here's everything you need to know about every Ford engine available for the 2026 model year.

By Brett Foote | 2026-06-05 12:58:01


VIEW MORE
story-7
10 Ugly Ford Trucks That We Still Kinda Love

Slideshow: 10 ugly Ford trucks that we still kinda love.

By Joe Kucinski | 2026-06-03 09:51:16


VIEW MORE
story-8
10 Things Every Truck Owner NEEDS (2026 Edition)

Slideshow: the best gifts for dads & grads

By Michael S. Palmer | 2026-06-03 15:43:58


VIEW MORE
story-9
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath

Slideshow: Called the Fortress, the 850-horsepower pickup combines Raptor underpinnings with military-inspired features, survival equipment, and a starting price of $285,000.

By Verdad Gallardo | 2026-06-03 11:38:36


VIEW MORE