Thursday, 28 August 2008

Fuel Sender, Tank & Filler

Having sorted out the geometry of the fuel sender arm and float it was time to fit it to the tank. To do this I drilled the tank for the fixing holes and inserted low profile M4 rivnuts - these have a very shallow head that pulls into the hole when fixed leaving a virtually flush surface:
I trial fitted the sender and checked the full and empty resistances for a final time. The sender was then fitted utilising the cork gasket supplied which was smeared with Blue Hylomar to provide a good seal. Fibre washers were used under the heads of the bolts to prevent any vapour creeping up the threads:
You can see from the above photo that it is necessary to modify the terminals on the sender to avoid intruding into the boot space. All that remained now was to fit the tank and connect the remaining hoses and wire up the sender and fuel pump:
Well..... the tank would have been fitted if I had remembered to collect the tank straps when I collected the tank! With everything now in place (nearly) I trial fitted the boot floor and pump box out one last time:
Nice and Neat. Next up for some attention was the Aston style fuel filler. This comes with no holes drilled in the fixing flange (although there are indents on the underside) so six m5 holes need to be drilled and then rebated for the heads of the fixing bolts. Next up you need to fabricate a rubber gasket to fit between the flange and the body - easily done with some 2mm neoprene. Here's the resulting parts:
The fixing flange was used to mark the fixing holes in the body.

First of all the flange fits to the body:

Then the cap is screwed on - make sure you do this with the cap open - this allows the catch to move in and give more clearance:

I've not bolted it in yet as I need to check something with GD. GD normally fit a vent pipe via a brass fitting into a tapped hole that needs making in the filler neck of the flange. However, the locking cap in the filler neck is vented and the Aston Cap itself is vented. So fitting another vent pipe seems a bit unnecessary?

A couple of weeks ago I ordered all the trim and seats etc on the understanding that it would take 6 weeks to manufacture. However the trimmers called yesterday to say it was all ready!! I asked them to send it to GD and I'll pick it up when I go down to get the windscreen and some other bits. I'm hoping that I'll have a windscreen within the next two weeks - the signs appear promising.

Monday, 11 August 2008

More Boot Stuff and Fuel Tank Sender

Applying four coats of varnish to the panels for the boot has kept me busy for a while, but having finished that it was time for something else.

There is no carpet for the rear of the boot bulkhead - so I decided to spray this black to cover up the patches of red gel-coat that showed through:That's better.

Next job was to sort out the fuel tank sender. Now the consensus of the forums is that the GD supplied sender does not work as it does not suit the shape of the tank. But I had to think that if GD used it then it must work??

So I set about measuring / cutting / bending to get the sender arm to what I thought was the right shape. The next step was to test it....??

I did this by fixing the sender to the tank with duct tape and connecting the terminals to a multimeter to check the resistance of the sender to compare it against the min & max values obtained with the sender out of the tank. Firstly with the tank the right way up:

243 Ohms compared to 243 out of the tank. I then lengthened the float arm until the reading reduced from 243 (i.e. float touching the bottom of the tank) - this was about 5mm.

I then inverted the tank to check the "full" reading - this was a bit out so after a bit of arm adjusting and float bending to avoid the float fouling the tank front / baffle..... :

23 ohms compared to 23 out of the tank.

After a bit more faffing about and checking I'm pretty happy that the sender reads full when full and reads empty when the float is about 5mm off the bottom of the tank. This isn't empty empty as this still leaves the two siphon connected lower parts of the tank at each end - these are below two horizontal baffles which effectively act as the "floor" of the tank as far as the sender is concerned. This should leave a few litres of reserve - which at 10mpg should last a couple of minutes!!

The final job therefore was to solder up the two sections of the float arm at the determined optimum length:Now....

... where's my windscreen?

Friday, 1 August 2008

Keeping Busy.....

Still no progress on the windscreen front....... So I've kept myself busy making a meal of something else!

The fuel filter and pump need boxing in..... The rear loom won't fit between the roll bar leg and wheel arch..... The rear roll bar leg brackets protrude into the boot..... There is a gap between the tank and back of boot..... So I've gone a bit over the top and solved them all:
No that's not a parcel shelf for sub-woofers! It's a false floor to the boot, this will accommodate the loom and the roll bar brackets and their seals (still in development). Another bonus is that after I have cut the holes for the roll bar legs I can use it as a template for cutting neat holes in the boot carpet.
Having the false floor also enables a neat job to be made of boxing in the fuel pump and filter:
The box out will be easily removable - I just haven't decided what sort of fixings to use yet.

The floor section still needs trimming along the front edge of the tank and then the whole lot is going to get three coats of exterior varnish prior to being carpeted (I've ordered carpets and seats etc. - lets hope they don't get here before the windscreen!)