Datsun Roadster Forum-311s.org

I want to pull the gas tank from my roadster while I am doing my stroker engine. I just drained to gas and plan to drop the tank sometime this week. Is there anything I need to be aware of while I do this.

roadstermike-

I haven't done this yet, but I don't think there's anything particularly bad about it. All the usual precautions about smoking, etc. A long time ago someone told me to fill the tank with water as a precaution, but that may be overkill. Maybe soak any threads you'll be working with with WD-40 or some such to aid removal, since they've been in a rather bad environment all their life. I believe all you've got is the fill neck (remove the rubber grommet from the trunk floor), the line to the engine (not sure how it attaches) and the connections for the gas gauge.

I'll be watching this thread as I have to drop and drain, too. But the "gas" in mine is so old that it smells like paint thinner. EEEWWwwwwwwww!!! Hmm. Maybe it is paint thinner. I did run an old Moretti 750 on paint thinner once when I was MUCH younger. I figured, paint thinner burns, so I can put it in the engine. It didn't work. Guess I shoulda used gas, but we didn't have any handy. This was before power lawn mowers were all the rage.

Anyway, if you come across anything out of the ordinary, please share it with us. Good luck!

Mike,

I just dropped my gas tank 2 days ago. I have to say I was shocked...and a little scared, at how easy it was! It took all of about 10 minutes once the fuel was drained out. Here's a step by step for you:

1) Drain/siphon out gas.
2) Disconnect supply and return lines at the tank.
3) Loosen hose clamps on fuel fill line in trunk. No need to remove it.
4) Loosen hose clamps on vent line in trunk and remove line.
5) Unscrew access plate in trunk and disconnect the fuel level sender lines. (If the screws are stripped or the plate is painted shut, don't worry. Leave it alone until step 7)
6) Remove forward bolt on each tank strap and slowly drop the tank down. It only weighs about 10 pounds. As you pull it down, the fuel fill line in the trunk will separate from the tank.
7) If you couldn't get to the fuel sender wires from the trunk, you will be able to now with the tank free from the straps.
Remove the straps. The mounting bolts on the rear of the strap have a bent end that simply hook into the underside of the car. That's right, in reality only two bolts threaded into the body hold this tank in!!!
9) After washing the tank out with soapy water, take it to a radiator repair shop and have them boil it out to get 40 years of crud out.

That being said, now the standard disclaimer: My car is a 68 2000. I have no idea if the procedure is different for a 67.5 1600 but I'm willing to bet it's similar if not exact. Good luck and no smoking!!!

Dave

Dave, very good explanation. The only difference between the early cars and the later is the lack of a fuel return line. One other thing--if the four little bolts holding the access plate in place will not budge throw some heat at them after you remove the tank. I had several snap off. Once the tank was out I shot them up with PB Blaster and removed them from the back side. A word of warning PB Blaster is highly flammable and I do not recommend heat with it. I had a heck of a fire removing some old rear brake lines once.

Steve

I have another step to add. This should apply to all years of Roadsters. With the tank out, remove the straps and J bolts at the rear. Measure the diameter of the J hooks and drill holes in the rear frame for them to hook into. When installing the straps, put the J hooks into the frame. This removes most of the stress on the trunk floor and prevents the cracks that are all to common.

That having been said, I don't recall seeing cracks on any of the pre 67.5 cars. I wonder if the metal thickness or quality changed then....

Excellent tip Sid. I think my trunk suffers from some cracks. At least I'm assuming that's why a previous owner covered the whole trunk bottom with fiberglass! Doh!

Do you need to modify the straps or the J bolts at all to get them to mount to the freshly drilled hole in the frame as opposed to the underside of the trunk?

Dave

Well, what I did when I replaced my tank is to undo the J bolts rather than the front strap mounts. By doing that, the adjustment changed when they were reinstalled (still plenty of threads to do it). If you undo the static end (front) you will have to adjust the J bolts as the straps will be at a different level than the holes where they used to go.

If I have to remove another tank, I will photograph the process and write up a tech tip...

Oh, OK that makes sense. Sounds easy enough to me!

Dave

It is remarkably easy todo and should go a long way to heading off problems. If you do it, take pictures! I don't know when I will be dropping the tank again, so if you can get the pics, I can tell the story (or you can do both if you like) so that the rest of Datsunland will know...

I'll do it! I need to wait for the tank to come back from being boiled out and modified at the radiator shop first. Maybe this weekend.

Dave

Off hand what does that boil amd re-seal process cost? I need to do the same.

Depends on where you live. It cost $125.00 to get one done here in the north bay.

Steve

I paid $95 up in Portland for jut the boil out and some custom welding. No seam sealing. Actually, the tank was quite clean inside and out. The only reason they boiled it was because I was having them weld in a 3/8 inch supply fitting and weld shut the stock supply fitting. For some strange reason, they didn't wan't to weld a tank full of gas fumes!!!

I'm in the Portland area (Tigard), bringing my 69 2000 back to life. Thanks for the advice on radiator and gas tank cleanup. Where are some good radiator shops in the area? I found Mac's Radiator on the web, but would love a recommendation.

I just dropped my gas tank on my 68. This post was very helpful and I took pictures at each step. The whole process took me a little over an hour--not bad the first time. Below is an illustrated version of Dave's step-by-step.


1) Drain/siphon out gas.
2) Disconnect supply and return lines at the tank.

There are two bolts, one for each line. I used a 15mm box wrench to get them loose.

3) Loosen hose clamps on fuel fill line in trunk. No need to remove it.
4) Loosen hose clamps on vent line in trunk and remove line.

You can see the two silver hose clamps. Use a #2 philips head screwdriver and loosen them all the way.

5) Unscrew access plate in trunk and disconnect the fuel level sender lines. (If the screws are stripped or the plate is painted shut, don't worry. Leave it alone until step 7)

Four screws, one at each corner, also a #2 philips head.

The fuel level sender lines just slide backwards off each post on the gastank.

6) Remove forward bolt on each tank strap and slowly drop the tank down. It only weighs about 10 pounds. As you pull it down, the fuel fill line in the trunk will separate from the tank.

The picture shows both bolts. Both are located towards the front of the gastank: one is by the supply and return lines and there is one on the opposite side. I used a 13mm socket with a long extension.

7) If you couldn't get to the fuel sender wires from the trunk, you will be able to now with the tank free from the straps.
Remove the straps. The mounting bolts on the rear of the strap have a bent end that simply hook into the underside of the car. That's right, in reality only two bolts threaded into the body hold this tank in!!!

I used a 13mm socket to remove the nuts on the j-bolts, then the tank came down and so did the j-bolts. There is one on each side of the tank, both are located at the rear of the car.
Wiggle the tank back and forth and get the rubber tube free from the trunk (it will remain attached to the tank), pull the hose clamps off entirely, and the tank will be free.


The tank has a drain plug at the bottom which can be used to drain any remaining fuel from the tank. Mine was a bolt and I used a 19mm socket to remove it, but the original drain plug calls for an allen wrench.


9) After washing the tank out with soapy water, take it to a radiator repair shop and have them boil it out to get 40 years of crud out.

A tip from Sid Raper:
I have another step to add. This should apply to all years of Roadsters. With the tank out, remove the straps and J bolts at the rear. Measure the diameter of the J hooks and drill holes in the rear frame for them to hook into. When installing the straps, put the J hooks into the frame. This removes most of the stress on the trunk floor and prevents the cracks that are all to common.


This picture shows the j-bolt hanging from the trunk supports and how easily it could be relocated to hang from the much more solid frame a bit further back.