Trainmaster
Old School Member
This post can serve as a warning and instruction to those who have need to remove their fuel tank straps. On the Gen4 trucks, Ford used "red Loctite" on the bolts, which thread into "j-nuts" clipped onto the frame. For those who never had the pleasure of experiencing these fasteners from hell, I'll offer some advice.
Try to loosen the bolts and you will very likely break the clips that retain the nuts inside the frame. Then the nut will spin with the bolt. You'll have to grind or cut the head off the bolt. Here's what I learned about these, the hard way.
If you heat the bolt head with a torch, the Loctite will quite quickly soften and you can carefully remove the bolt with the proper 15mm socket. As soon as turning becomes even slightly difficult, apply heat again, and loosen some more. Only a 3/4" band of Loctite is applied to the bolt, so you'll probably have to heat the bolt two or three times. Of course, a $200 electric induction heater would be the best and safest tool for this, avoiding most risk.
So how do you heat a bolt buried an inch from a plastic tank of fuel? Without going into the possible dangers, I made an insulating shield formed against the tank. You can use aluminum flashing, possibly aluminum foil, a thick asphalt roofing shingle... etc. Use the smallest flame on the torch and heat it for maybe 15 - 20 seconds. Don't be an idiot and watch your flame.
If you didn't heat the bolt, and broke the ears that secure the nut to the frame, you may still have a second chance. The j-nut on the front strap is accessible through a slot on the side with an open end or box wrench. It's a regular 15mm nut welded to the clip and extends tall enough to hold a wrench. You can try holding that nut, heating the bolt and you'll get a second chance at removing it. The rear strap nut may also be accessible, though I didn't check this too well, as I didn't break that one. Look to access that from above somehow by the driveshaft.
Now if you really screwed this all up, as I did, and the nut is turning with the bolt and all seems lost, you'll have to cut the head off the bolt. I used a Dremel tool with a reinforced cutting wheel and a steady hand. Fashion a guard to protect the plastic tank. If you hit the tank with the spinning cut-off wheel, you'll cry lots of tears. There are also some sparks that are concerning. Make a guard described above. I used a thick piece of asphalt roofing, so the wheel could bounce off it on an occasional hit and so the sparks would be deflected.
This is no job for the faint of heart. I'm not preaching the dangers involved. We're men and we know all this. The dealer claims they cut the straps, remove the tank then wrestle with the bolts, to the tune of $ 3,700. You can do it in two hours for less than fifty bucks. Oh yeah, wear eye protection. And using anti-seize may help the older you one day replacing the fuel pump.
And next time your fight a 3/8" bolt running up into a j-nut clipped onto any frame channel, you can BET, that Ford put RED Loctite on it that will make you cry when the clip breaks free. And to make matters worse, some of their Red Loctite is colored blue.
Ford bolted tank straps for 75 years without red Loctite. I never heard of one falling out. WTF, Ford??
With only 23,000 pages in the shop manual, I see you didn't have room to mention a word about these bolts either.
Try to loosen the bolts and you will very likely break the clips that retain the nuts inside the frame. Then the nut will spin with the bolt. You'll have to grind or cut the head off the bolt. Here's what I learned about these, the hard way.
If you heat the bolt head with a torch, the Loctite will quite quickly soften and you can carefully remove the bolt with the proper 15mm socket. As soon as turning becomes even slightly difficult, apply heat again, and loosen some more. Only a 3/4" band of Loctite is applied to the bolt, so you'll probably have to heat the bolt two or three times. Of course, a $200 electric induction heater would be the best and safest tool for this, avoiding most risk.
So how do you heat a bolt buried an inch from a plastic tank of fuel? Without going into the possible dangers, I made an insulating shield formed against the tank. You can use aluminum flashing, possibly aluminum foil, a thick asphalt roofing shingle... etc. Use the smallest flame on the torch and heat it for maybe 15 - 20 seconds. Don't be an idiot and watch your flame.
If you didn't heat the bolt, and broke the ears that secure the nut to the frame, you may still have a second chance. The j-nut on the front strap is accessible through a slot on the side with an open end or box wrench. It's a regular 15mm nut welded to the clip and extends tall enough to hold a wrench. You can try holding that nut, heating the bolt and you'll get a second chance at removing it. The rear strap nut may also be accessible, though I didn't check this too well, as I didn't break that one. Look to access that from above somehow by the driveshaft.
Now if you really screwed this all up, as I did, and the nut is turning with the bolt and all seems lost, you'll have to cut the head off the bolt. I used a Dremel tool with a reinforced cutting wheel and a steady hand. Fashion a guard to protect the plastic tank. If you hit the tank with the spinning cut-off wheel, you'll cry lots of tears. There are also some sparks that are concerning. Make a guard described above. I used a thick piece of asphalt roofing, so the wheel could bounce off it on an occasional hit and so the sparks would be deflected.
This is no job for the faint of heart. I'm not preaching the dangers involved. We're men and we know all this. The dealer claims they cut the straps, remove the tank then wrestle with the bolts, to the tune of $ 3,700. You can do it in two hours for less than fifty bucks. Oh yeah, wear eye protection. And using anti-seize may help the older you one day replacing the fuel pump.
And next time your fight a 3/8" bolt running up into a j-nut clipped onto any frame channel, you can BET, that Ford put RED Loctite on it that will make you cry when the clip breaks free. And to make matters worse, some of their Red Loctite is colored blue.
Ford bolted tank straps for 75 years without red Loctite. I never heard of one falling out. WTF, Ford??
With only 23,000 pages in the shop manual, I see you didn't have room to mention a word about these bolts either.
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