Right,

Ali tank for my locoblade.

Not injection so no fuel return needed.

One internal central baffle with gap across the top and bottom corners cut off.

Big tube on bottom will be cut shorter and capped and the fuel will be taken out of a small pipe welded to the side of this tube.
The flat cap on the bottom of this tube will be tapped and a bolt screwed in it on the bottom to enable the tank to be drained.

Top and 2" inlet pipe to be welded on yet.

Small pipe for a remote breather also to be welded to the top of the tank near the 2" filler pipe, or even taken off the 2" pipe that will stick out from the top of the tank.

Pat...
Rescued attachment Tank1.jpg

And another pic:
Rescued attachment Tank2.jpg

Pat,

surely the cardboard for the baffle will go all soggy when you put petrol in????



only kidding, looks good when you starting on one for me??

Ray

I think I recognise that tank...

Helfire - it's eaither the one you saw that was held together with gaffa tape, or it's merely the material and welding you recognise

Ray - would love too, but Tigging isn't something I am capable of and getting my friend to do it as a favour.

Any problems with the design?

Pat...

quote:

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Originally posted by rayward
surely the cardboard for the baffle will go all soggy when you put petrol in????

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tank looks good so far some swaged holes in the baffle will ease the pressure on the welds regards trev

Hi Trev,

Won't that defeat the object of the baffle?

There is a 1" gap at the top and the two corners will be cut out.

It's also all made from 3mm ali and baffle will be welded fully up each side and across the bottom.

Thanks,

Pat...

you even wouldn't need to completly weld it up...

2 1 inch welds would be plenty..

at least if they are good welded offcourse

Tks

If you want to be fancy you could always make up a trap door mechanism in the baffle so it allows fuel to flow towards the pickup, but not away from it. An aluminium piano hinge with the pivot pin knocked out and replaced with welding wire (to make it a very loose pivot) is ideal

Sounds good Chris, but too fancy for my needs.

Think with the small resevoir on the bottom, it should be fine.

Pat...

Yep, was just saying in case you wanted to be tarty

The only thing I would say is that a swirl pot / reservoir thats the full width of your tank might be better at catching sloshed fuel than your round one, if its only half the width of the tank then fuel can pass on either side without falling into the pot, whereas if it was rectangular shape (maye with an angled base to further funnel the fuel towards the pickup) and all the way across it might be even more effective, especially considering that the tank will likely be at a small angle when mounted in the car so when low the fuel is likely to run along one edge of the tank or the other, not down the middle IYSWIM

Chris

[Edited on 21/11/05 by ChrisGamlin]

all the tanks i have comeacross at work all have holes in them from gp cars to rally cars.ps i have holes in mine

Hi,

So if I move the small resevoir to the back edge (towards the front of the car and then drill a few big goles in the baffle, that shoulw be fine?

Trev - how about a couple of 50mm holes next to each other?

Pat...

Yep moving it against the front edge would be better,

I would maybe put a few holes in the baffle plate in the top half because if the fuel is that high, it isnt going to surge anyway so no point in putting lots of load on the baffle plate when the tank is nearly full. Personally I wouldnt put any more holes down the bottom though.

Chris

yes two or three will be ok if you dont put any the welds will break trev.

Like this?
Rescued attachment Tank2.jpg

Won't it be easier to have a half height baffle?

Pat...

quote:

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Originally posted by Trev D
all the tanks i have comeacross at work all have holes in them from gp cars to rally cars.ps i have holes in mine

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I would put two baffels in, spaced to be under where the securing straps are to go over the tank. I would be happy with full height baffles with generous corner cut outs.

Cheers

Fred WB

Don't see the point of two baffles when I have my small extra resevoir (All credit to Rorty for this idea).

Will leave it almost full height and drill one 75mm hole in the centre.

How big for the bottom corner cut-outs? 1" x 1" ?

Pat...

If you measure the interior of your tank and cut a square (or rectangle) to suit, and then make it as close as possible into a symetrical octagon, the size of the corner cut-aways will be proportionate to the size of the tank.
I often use your method of constructing a small reservoir for the outlet, but I cut the tube on a 30 degree slant to accomodate a drain plug.
The outlet is usually about 10-15mm above the level of the drain to avoid picking up crud, and welded into the remaining round part of the tube.
I used to run the minimum amount of fuel to see me through a race and that baffle/reservoir works well with all the bashing around off-road.

Octagan it is then!

Thanks Rorty.

My resevoir will be on a slight angle anyway as the ank does not sit flat in the chassis, but there will be a drain plug in the bottom of this tube and i'll put the fuel outlet 15mm higher.

Thanks,

Pat...

Baffle done and welded in - full bead across the back at the bottom and two 2" beads up each side - one on the front on one side and one on the back on the other side.

Pat...
Rescued attachment Baffle.JPG

I have a plan to combine baffle with swirl pot using the arrangement shown in the 'paint' drawing below. Any reason why this shouldn't work?
BOb
Rescued attachment tank.GIF

The 'baffle' would reach ~3/4 the way up the tank
Bob

I've seen something similar, though constructed in a corner of the tank.
I would prefer the second option.

I had thought of having a pick up point at both LH and RH sides of the tank, with piping going to a T before the fuel pump, so you would always have a head of fuel when the car is cornering left or right, good or bad idea?

Cheers

Fred WB

If you have (say) 1/2G sideways force on a long bend, the fuel will slop to the left in the connecting pipe exactly like it does in the tank, leaving the pump suckin air from the 'high side'.
I'll make a model of my swirl baffle out of plastic & let you know how it behaves (sounds like the sort of fun thing I can involve my daughter in!)
cheers
Bob

If you have (say) 1/2G sideways force on a long bend, the fuel will slop to the left in the connecting pipe exactly like it does in the tank, leaving the pump suckin air from the 'high side'.
I'll make a model of my swirl baffle out of plastic & let you know how it behaves (sounds like the sort of fun thing I can involve my daughter in!)
cheers
Bob

Hi Pat

Just in case you hadnt thought of it, don't weld the top of your tank on until you've mounted your fuel sender you'll get with the Digidash, it would be easier to mount it into a panel where you can get at both sides, and you wont get shed loads of swarf in there to wash out!

Also, I think you'll be OK but you might just want to make sure that the sender can swing through a full arc with the baffle in place before cutting any holes, otherwise you might need to move the baffle slightly or get a plunger type sender instead.

Chris