ford gpa g504

Gentlemen,
Some questions about hull bottom plugs. My new GPA had no plugs with it which will make the first swim an interesting experience. My project GPA had one plug which I have cleaned and attached photos. Is it correct? There is only a very slight taper on the thread and it is steel whereas all my DUKW bungs are bronze. The parts list shows 2 different plugs, 3 of each, what is the difference? Are the plugs easily found? If not I will get some made in bronze when I am in India next month.
Thanks in advance.
Bob





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Bob this looks like ok to me ,there are also smaller plugs ,if you can make them for a nice price I can use a few bigones.
For the bigones you can also use gascan or oildrum plugs they fit great,.
I use one from a gascan it is very easy to unplug after a swim.
The smaller ones are easy to get .

I send you a email about it .

Regards Peter

Having today looked under the good GPA I have found a small plug which is a smaller version of the other one I have. So there are 4 large and 2 small plugs in the bottom of the hull. I will get some made, I need 2 sets for myself. I will also need a set of the fittings the plugs screw into for the project GPA, does anyone have these or shall I get some made?
Regards
Bob

Bob,
I had some fittings from Nils Broch
Cees

Everyone,

Does anybody have a picture of what the original bottom plugs look like? I would be interested in seeing what an original one (large and small) looks like.

Thanks,

Donovan.

Here are the 2 plugs I now have, they are in steel and have a slight taper. The large one has a 1 inch square hole and measures 2 inches across flats on the hexagon. The small one has a 0.5 inch square hole and is 1 inch across flats on the hexagon. As far as I know they are original and are the ones I will have copied, but in bronze. If anyone knows that these are not original please let me know.
regards
Bob



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Bob

They are the right original ones!
You can use an American jerry can for the right
thread / hole in the bottum.

Greetings Bob

Hi Bob,
If you do get the drain plugs cast please keep me in mind for 2 sets. I would also be interested in the female hubs that are welded in to the hull.
I need one full set of these + a 2 extra of the large ones.

Best regards

Richard Sanders

richardfs wrote:Hi Bob,
If you do get the drain plugs cast please keep me in mind for 2 sets. I would also be interested in the female hubs that are welded in to the hull.
I need one full set of these + a 2 extra of the large ones.

Best regards

Richard Sanders

Richard the female hubs are the same as the US jerrycan ,oildrum is the same size [ this is for the big ones. I think that the smaller are also some kind off oil/gas or sae fitting.

Peter

I might be interested, depending on price. Thanks for checking

Jerome

Hello Everyone,
I'm not getting obsessive about this, honest. But having had another look underneath, this time with my glasses on, I find there are 5 of the large plug holes, not 4 as I first thought and that also the drain plug in the rear drive shaft housing is the same as the 2 small hull plugs. So that makes
5 X 2inch and 3 X 1inch in a set (so far). Also, what provision is made for draining the hull in front of the front axle and the 2 rear quarters behind the rear axle? There are small threaded holes in all 3 locations in my GPA but these may have been added at some time, anyone know what is correct? Also, having tried one of the large plugs in a gas can neck I do not think the dimensions are the same, the plug is not tight in the neck and can be screwed by hand right to the end of the thread, perhaps the fittings in the hull are tapered but the gas can neck and cap are not. The gas can cap has a flange and gasket on it which makes the seal. The GPA hull plugs (and the DUKW bungs) rely on the taper to make the seal and hold the plug tight in the hull. That is my theory anyway.
All the best,
Bob

Bob,

I believe there was a FSMWO for the rear of the hull... on either side of the tunnel towards the front near the rear axle if you get where I'm talking about... the metal that has the ribbing horizontally on it... two small plugs were put there.... I had an NOS hull at one point that had them there so must have been factory in the end... but I had them put in my hull when redoing it since you correctly observed that there is no provision for taking water out of there... the front uses the bilge pump... but can still leave a little water there..... I don't believe there was ever a FSMWO for the front

Tony

Bob.

I am interested to in 1 set if the price is right.

Cees

Bob,

I'm interested in the small ones only.
Thanks.