What a Day! Removing the fuel tank is a bitch!

[g-mam]

First I wired the new Igniter and Flamethrower like it should be, looks neat and clean now.

 

I decided it was time to remove the fuel tank. I drained it, and it had some dirt in it. I loosened the clamp at the filler neck. Then the problems set in. The hose clamps on the vent, return, and fuel feed were rusted tight. Soaking in breakfree did nothing. I ended up cutting the hoses deciding to replace with new anyway. Then the rubber between the tank and filler neck just separated at the tank. This may be where my leak was all along, dripping along the seam. Either way, I am going to use the Caswell sealer to make it good. Two of the 6 bolts holding the tank snapped. Not sure how I will tackle getting the broken pieces out. At least they were not on the same plate.

 

I purchased a gas can and rigged a hose to the line the tank connected to. Works perfect so I can move it in and out of the garage.

 

I was never so dirty in my life, with all the crap falling off the tank. I feel like I have made some good progress today. Next I will remove the carb while it's parked on the street, and work on rebuilding it.

 

So, here are some questions to those who have done this before:

 

1. Is the rubber between the tank and filler neck an item available at any parts store?
   
2. How do you get that sending unit off, and do I need some new gasket?
   
3. Any ideas on removing the broken bolts?
   

[mklotz70]

these guys will have the hose and they'll ship. You can probably find somthing similar a lot closer. I doubt normal parts stores would have it...maybe NAPA.

 

I've got 5 dead tanks around here and still don't remember off hand how they come off. The 320 has screws....since you didn't mention screws, I'm guessing is has the lock ring on it. Brass drift, hammer...tap the tabs that stick up.

 

When we got Paula's 521 years ago...same prob with the bolts being broken. IIRC the nuts are welded to a metal strip and not directly to the tank. Just make a new one with new nuts or cut/grind the old nuts off and weld new ones on. Other wise, soak with penetrating oil and drill the center...then try an easy out. Or drill it to the next size and tap new threads.

[Jester]

I had to replace the filler hose as well. The first time I filled my '75 it let me know there was a problem. LOL I picked up a piece from CarQuest. Not cheap hose!!!

 

As to the bolts, you may try using vise grips and taking them out the top side of the nut. The part inside the nut should be clean and come out fairly easy. If not, replacing the nut all-together like Mike suggested would do the trick.

 

I have taken three tanks out of 620's and don't recall. I never even took the senders out. Sorry.

[g-mam]

Place in town said they have different size hose for the filler necks. This one has a bend, but I hope it's flexible enough to use. Those vent hoses I had to cut led to what I guess is the reserve tank behind a plate. I am sure the hose clamps on those are shot too. I'm hoping I can gain access to the fittings. I'm almost afraid to try to remove it, but I have to replace them.

 

I'll clean around the sending unit and see if I can get it off.

 

I had to reach up and blindly remove the wires from the sending unit. Does it matter which wire goes where?

 

I'm not giving up yet!

[Pacific coast Datsun]

You can remove the tank brackets off the bed & get the busted bolts off that way. And...the sender has several small "tabs" that are raised. Take a flathead screwdriver & lightly tap on them counter clockwise [i believe] & it'll come off. I also wondered about the 2 wires..ive had mine hooked both ways & the gauge still works.

[Jester]

Make sure you clean the area around the sender well as to not get any chunks in the tank.

[g-mam]

You can remove the tank brackets off the bed & get the busted bolts off that way. And...the sender has several small "tabs" that are raised. Take a flathead screwdriver & lightly tap on them counter clockwise [i believe] & it'll come off. I also wondered about the 2 wires..ive had mine hooked both ways & the gauge still works.

 

I'm afraid to even try to remove those brackets. If nothing else, I will drill new holes beside where the stripped bolts are and put a new bolt in there. I don't think it's a showstopper.

[g-mam]

these guys will have the hose and they'll ship. You can probably find somthing similar a lot closer. I doubt normal parts stores would have it...maybe NAPA.

 

Who is "These Guys"

[mklotz70]

DOH!! Read my siggy!!

 

Oil Filter Services Co

615 SE Market St

Portland, OR 97214-3522

(503) 232-5126

 

They also have bends. You'd need to have your diameter and length when you call them. I don't know of a website...if you find one, let us know :)

[datzenmike]

The sender has an O ring to seal it. Get a new one. Make sure the hose isn't rubber or the gas will dissolve it. It has to be resistant to gas. O ring too.

[g-mam]

I thought there was no way I'd get that sender unit out with the rust on it, but I soaked it in break-free for an hour or so and was able to tap it out after I dug the rust around it out. The O-Ring looks like new and still soft.

 

It's going to take some TLC, dremel, and Por-15 on the sending unit top to get it clean.

 

Now I get a good look in the tank. Shiny in spots, and some rust. Still couldn't find where it was leaking. Some of the seams along the lip have separated some and rusted away, but when I washed the tank out I didn't see any leakage. May still have been the filler neck. Either way, I need to address the rust inside, so it will get a coating no matter what, plus a good coat of Por-15 on the outside.

[Mini-L320]

The best thing to use on rusted gas tanks is KREME. its a 3 step process. go to a local parts dealer and ask to see if they have it. I got mine at a ATV store. Ask for KREME, the 3 step to fixing rusted tanks. your probably gonna need 2 kits for your tank.

 

http://www.carparts.com/KREEM-LIQUID-FUEL-TANK-LINER-KIT/GP_2000795_N__10618.car

[Mini-L320]

the last step is this white Liquid stuff that covers up any small holes so it wont leak again.

[g-mam]

Today I found two pinholes in the tank. I have JB Welded them, then I will seal the inside with the Caswell Epoxy.

 

I need to do it soon, even the clean spots in the tank have already rusted over. I wanted to get the holes repaired before the sealer.

[g-mam]

I got a new piece of filler neck hose last night. This is 2", which is slightly too large. I think I can clamp it down enough. The next size down was 1 3/4, which was way too small.

 

Since I had to cut the vent hoses, I now have to access the other end of them to replace. There seems to be a cover at the top of the wheel well, with the reserve tank there. I'm hoping I can get this off.

[g-mam]

Well the tank is coated with the Caswell treatment. This took a lot of time. The prep work takes the most time. Clean with DAWN, then drywall nails and Acetone, then just Acetone. Dry it out, and ready to coat.

 

The JB Weld sealed the pinholes on the outside, and paid extra attention to getting this area coated on the inside.

 

The stuff is clear, so that makes it harder to see if everything is coated, but I'm sure I got it all coated. I rolled that stuff around for 1/2 hour until I felt my arms would fall off.. You are supposed to drain it all out when done, but that was inpossible with the 620 tank, as the filler entrance has a lip inside. I got as much as I could out the hole for the sending unit. I didn't want to drain it through the drain plug and clog the threads. I had the hole plugged with Playdough.

 

What I did drain back out got so hot I thought it was going to melt the bucket! It's now set up, and an inspection mirror shows the entire tank is coated well. I used pipe cleaners and compressed air to make sure the pickup and vents were clean. I also coated the filler neck.

 

I hope this solves it. It might not hold as much gas now :D

 

This weekend I will coat the entire outside with Por-15.

[herculesinwyoming]

thats my next job too, is clean up the tank, i start in the morning july 17

[g-mam]

If I had to do it again, I would crack all the bolts and soak them again for a few hours in some kind of break free.

[g-mam]

I have now POR-15'd the entire tank, and filler neck. Today I tried to get the two broken bolts out, but didn't have much luck, so I decided to take the tank brackets off. Well, in that process I broke two more bolts :eek:, but I was able to get one of those out, and the other, I just drilled a new hole below the old one. I will have to but a washer and nut on it, but it will be fine.

 

I also removed the cover over the reserve tank, and put new hoses on for the tank vents. Looks like there is another line there for the return that goes to another hard line. I didn't remove that one, but I'm thinking of replacing it just the same, just to have all new hoses on. The two tank brackets I had to removed were cleaned and POR-15'd, along with the reserve tank cover.

 

Tomorrow I am ready to put the tank back on. I may rinse it once more to make sure there isn't any dirt, stray strands of epoxy or anything else in there.

[g-mam]

The tank as been remounted, all connected up. Little concerned with the kink in the filler neck hose since I could only find straight ones, but I was able to pour fuel in okay, so I'm hoping it's not an issue. Need to go get some fuel, then the real test is to fill the tank :-)

 

If this is all fine, the carb come s off next.

[mklotz70]

Maybe you could use a piece of exh pipe bend as an elbow with two short pieces of straight hose on either side.

[g-mam]

I think I'm good now. The slight kink didn't make an problem fueling it. I have e3/4 tank in it now and no leaks.

 

BTW, I take it the 11 gal tank is USEABLE 11 gal.? I dumped 11 Gallons in from empty and it's only 3/4 full right now. I'm going to drive it to the station tomorrow and top it off for the REAL leak test :-)

[herculesinwyoming]

drained my fuel tank today, and it all came out clean, not dirt or rust at all.

i think im just just going to add an extra filter and, fill it back up.