Removing the Gas Tank
©By: John T. Blair (WA4OHZ)
1133 Chatmoss Dr., Va. Beach, Va. 23464; (757) 495-8229
Originally Written: Circa 1998
Last update: September 2, 2009 - Reformatted page & Corrected email address, added pictures.
In the past, I've had several people ask me about removing the gas tank. Unfortunately, when I restored my 4/4 it was about the last thing removed, so I really didn't know if or how to do it without completely disassembling the car.
Fortunately, we'd had a discussion about pulling the gas tank on the Morgan mailing list, and I got most of the of the answers I needed about removing the gas tank, and it is doable without removing the rear deck or pulling the body. It has to come out from under the car!
When I restored her, I did have the tank cleaned, and lined. That was back
in the late 80s or early 90s. Since that time, the gas has changed, especially
with the addition of Ethanol. It appears that Ethanol is not compatible with
what ever the older tank lining was made of. I couldn't keep gas in the tank over three months without having to drain the tank, pull and clean the fuel pump and the float bowl, and blow out the lines. A real pain. I've fought this problem for years now. And last year I had all kinds of problems. Culminating with the
original fuel pump dying while on the way to a cruse-in. Luckily my wife was following me and I had ordered a rebuild kit and a new fuel pump. I sent her
home to pick up the new fuel pump while I started taking the original one off the car. She got back with the new pump, and I was back on the road about 15 minutes later. I made it to the cruse-in, but about two hours late.
Rear of My Morgan
Zenith 32VN Carb on my '65 4/4 Series V
The new fuel pump has helped quite a bit, but I'm still having some problems with the
gas going bad very quickly. So today (Sept 2, 2009) I went over to my dad's to pull
the gas tank and have it cleaned and relined.
The first problem to over come is that the car had been sitting for quite some time and the fuel in the float bowl had evaporated. Trying to use starting either and cranking the engine, until the engine gets fuel usually kills the battery. So I used a trick I discovered a while back.
How do you get fuel to a carburated engine easily?
Remove the float bowl and fill it with fuel and replace it. Simple! Boy I wish I'd
have thought of that years ago. Trying to get my Morgan started after she has sat
for some time always been a royal pain. Needless to say, I now do this all the time.
So now I can back her out of the garage to drain the old gas and drop the gas tank. And still be able to drive her back into the garage.
The following is the procedure to do pull the gas tank. It took me about 2 hours from start to finish, including about 30 minutes to drain the gas tank.
Empty Float Bowl
Spare Tire Removed
Gas Tank_Drain plug and mounting bolts
T nuts in Tank Bed
|Tip #1 - A neat trick some people told me about when I was restoring my car was to use "T" nuts to hold the floor board and rear fenders to the car. This works great as the nuts and bolts don't get all the dirt on them and its easy to get the bolts out. The reason I mention this, is that you should put "T" nuts in the top of the gas tank deck and then insert the bolts coming up from the bottom of the car to hold the tank in place. Now you don't have a problem with the carriage bolts spinning in the wood, etc.
Gas Tank on the Ground
Tank Bed slid forward
Tank Bed Slid Back with Tank Removed
You may also find that most of the nuts and bolts have rusted and may make
it difficult to get things apart. Most of the bolts on my car were
in pretty good shape as I've owned my car since 69 and it's always been
garaged. However, I replaced all the NON structural nuts and bolts with
Stainless. All structural bolts (i.e. front and rear suspension) with
Grade 8. My car was also done with Whitworth nuts & bolts. I converted
over to SAE. They are just easier to get. The newer cars, sometime in the
mid 70s - I think, are metric.
One final note, I noticed that my gas gauge had quit working when I ran out of gas with the gauge showing about 1/2 a tank. So when I pulled the tank (Sept 2009) to have it relined I had to pull the sending unit out. I found the problem. The float was stuck, not moving. I removed the top (4 small screws) and squirted some WD40 into the sending unit and on the outside where the shaft goes into to the unit. After working it for a few minutes, it freed up. So if you gas gauge isn't working, you might want to check this. You don't have to drop the tank to get to the sending unit, just remove the spare tire and the metal plate under it. It might be a quick fix.
Fuel Sending Unit
Hope this helps and enjoy your Morgan!
A couple of comments about leaking gas tanks.
Phil Roettjer, owns a 1967 +4 and has had problems with his gas tank:
I have the gas tank out of my +4 since it was also leaking. What I discovered is there are stress points at the bottom where the sides of the tank are soldered on. There are two bolt holes on the flanges on each side and the side-to-side motion of the car plus vibrations puts tremendous stress on these solder joints. So any padding that would allow the stress to be transferred away from these joints should be beneficial. The leaking problem in my car is not due to corrosion, but due to breaking the solder joints at these stress points. So I do plan to have some sort of rubber or padding at the bolting points to help relieve the stress. I would also recommend sealing the inside of the tank with a compound such as the POR15 tank sealer.
Greg Solow of the "Engine Room" writes:
I have had my car since 1965 when I purchased it new. The only problem I have had with my gas tank , and I have seen the same problem in many other cars, was that the two baffles which run fore and aft dividing the tank roughly in thirds, came unsoldered from the inside of the tank and fell to the bottom where they would slide around and sometimes interfere with the correct functioning of the fuel gauge. To repair this, I ultimately drilled 8 holes through the sides of the tank so that the baffles could be pop riveted into place securely. Then the steel pop rivets were silver soldered over to plug the holes . There have been no problems since. I believe that the original mounting, solidly on good wood boards is an excellent solution. The leaks are caused by either the boards coming adrift from the chassis, or the tank itself coming loose from the beards and moving around then stressing the soldered joints. The two wooden boards are fastened together by two metal straps that are screwed into the wood. Then the boards are fastened to the fuel tank by four bolts that pass through the mounting brackets that are soldered to the ends of the tank. Then this whole rigid assembly is attached to the frame by three screws only. There is a good reason for that. Three points determine a plane. With the board platform attached in this manner, the boards and the tank form one unit that is insulated form any flexing of the frame, i.e.. the frame can move around but the tank will not be "bent" or twisted.
My recommendation is to do a good solder job on the tank. Secure the baffles if they have come loose. (You can see them with a mirror and a light through the sending unit hole). If the tank is not rusty inside DON'T seal it. I believe that "sealing" is to stop or prevent rust, not stop leaks. Make sure that the support boards are in good shape, especially at the forward corners where the two front bolts that go through the chassis are located. Tighten everything up and keep it tight and you should have no problems.
We have found that most of the engineering that went into Morgans was and is quite good. Most things do not need to be reengineered! The areas where things can really be improved are in the fit and finish and sometimes in the materials used. Morgans were "Built to a price" during the sixties, remember a new +4 cost more that an MG-B, but less than an Austin Healey 3000. The way Morgan kept the price down was by using the least expensive materials that would do the job, and I don't necessarily think that there was any thought of the cars being on the road 30 years later. After all, by 1964, when I first visited the factory, the 3 wheeler was really an orphan, as far as Morgan was concerned, and the last one produced was only 11 years old then.
Bob Nogueira also writes:
I know of what you speak (Leaking gas tanks). The Duchess tank leaked at the same joint. It took me forever to discover the leak as it was so small that fuel never dripped to the ground but collected between the tank and wood boards. After repairing the tank, to keep from stressing the seams again I used two metal straps with rubber under them. They start and end at the rear cross member, going over the tank down to the boards and under the boards back to the rear cross member. On top of the tank I have two adjustment screws to tighten up the straps. With this arrangement I don't have to use side flange. I also feel much more secure knowing my gas tank is not being held in place by two soldered flanges.
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