Downunder turbo oval & Datsun 510 adventures

[petew]

Got some threaded fittings to weld onto the tank. Is there anything I can wrap round the threads to protect them while welding?

[rubenski]

A bolt? Or 2?

[petew]

Last night's effort...



Managed to get into every corner between the drill, grinder and dremel. Trying to sort out a plan for baffles now.

[Piledriver]

Trying to sort out a plan for baffles now.

Perhaps a stainless utensil holder as a baffle around the pickup?

[petew]

Been looking at a stack of different baffle designs across the web. In the end, I wanted something that wouldn't screw up after I'd welded it altogether and put a coating threw it. This was the best collection design I could find. Apparently, it's a Honda S2000 inspired thing. Basically when the fuel gets into the maze, the only way it can get back out is the same direction...



Translating it into steel without a folding machine was a little tiresome but it worked out ok. I just need to adjust it a little more and it's ready to weld on. You can see the X where the fuel pickup point is.



The panel it's sitting on is going to be welded in as the new tank bottom. I'll also be adding some simple side baffles to stop the fuel from sloshing side to side. They won't perfect match the profile of the tank, they're just there to slow things down a bit.

[creber1951]

That fuel pump is the same as early V6 Commodores and you can get the OG rubber joiner in 12mm one side and 8mm the other.I used one on my car.I think there is also a model that used an elbow there.Ebay should be helpful.

[petew]

Could you put up a link?

[petew]

Some more baffle work this evening after some racing today... mmm valentines racing, mmm...



Two little flaps down the bottom that let fluid in easily, but not out so easily, a few holes higher up and the odd gap round the edge.





Please ignore my welds, the tank was pretty awful to weld on.

[petew]

More work on the tank.... I added some more baffling to the top of the side baffles to prevents fuel sloshing round in the top of the tank.





With that all done it was time to weld the fuel collector on the the bottom on the tank. Despite really careful prep of the steel, I was having on-going issues with welds being spattery and awful. In the end I discovered that the wire-feed potentiometer was dirty. Having pulled it all apart and given it a good clean out, I ended up finishing the weld on a slightly higher setting. This time the final welds were really on the money.





So I have a little grinding back to do in other spots. Even so, I'm pretty confident it's not going to leak. It will still get an internal coating too.

[petew]

Right, so it turns out my fuel tank is really a "fuel sieve". I tested it will soapy water and compressed air and the welds have tiny leaks round the bottom. I'm not too phased by that because the tank sealer will fix most of the perimeter welds. The fittings are a different story. Both have welds that are leaking a little. I can try the tank sealer, but I'm concerned it might not seal them as well.

Thoughts?

[miniman82]

Shuold gave TIG'd.

[Clonebug]

Do some brazing with a torch and fill the holes.

[petew]

Right, so I've decided to try again with the fittings. I'm cutting them off and a mate who works in refrigeration is going to silver solder some new ones on. If that doesn't work, then I'll have them tig'd on.

[Piledriver]

Do some brazing with a torch and fill the holes.

Ummm.. what he said.

I would not trust any solder job other perhaps to seal the remaining holes... you welds are probably fine structurally.
The sealant is very likely to fix it anyway.

I suggest: cut it off and try again with the MIG (you CAN do it), or go direct to TIG, or TIG silicon bronze braze, or gas braze.
(silicon bronze TIG would be my choice, but I have some rod and a TIG setup handy)

[petew]

Could I get enough heat into it to braze with Butane? And what sort of filler do you suggest?