Does anyone have plans/drawings of thier cooling system layout, I've made mine on my midi but seem to be getting air locks on it, I want to just check my plumbing to what others have done.

1st Rule is You should have only one pressure cap.
2nd Rule is make sure you have bleed point on the top of front rad.
3rd Rule is You need continuous bleed from the cylinder head to the header tank/swirl pot.
4th Rule You should have a by-pass connection.
5th Rule if You should have a couple of small bleed vent holes in the thermostat.

To cover rules 4 & 5 I would use a Landrover/MG-Rover PRT thermostat (more correctly called a PRRT) these work really well on MGTFs .
On MGTF and Elises it can be fitted either in the engine bay or at the front behind the rad.

See ebay item 290404132132
also see http://wiki.seloc.org/a/Fit_a_PRRT
Rescued attachment prt.JPG

In my experience the most important thing is a small bore pipe to wherever bubbles accumulate to either the highest point, if you rad is at the front then you need an expansion tank close to the engine to bubble in to.

If you just have large hoses all that happens is that the steam bubbles off the cylinder head pushes the water along and you end big air pockets.

Small air bleed-offs do not displace the water so you get away from this.

Bit of a poor explanation but hopefully you get the gist.

Regards Mark

my 2007 R1 stock has two inlets/ one outlet into the radiator. Well i put the radiator up front so it was no longer the highest point. I welded an aluminum swirl pot with the radiator cap on the top. This sits in the back engine bay where the two hot lines enter and one hot line exits to the radiator. I welded up the hole from the ond fill point and one of the inlets on the radiator. So now its just the engine, swirl pot, and radiator with single inlet/outlets. Its untested, but its been more then successful on every FSAE car i have built

take a look at my gallery near the bottom from "coolant tanks" downward. my coolant system works perfectly.

as suggested you definately need a small bore bleed pipe from the top of the rad into your expansion tank. ive also got a swirl tank near the engine on the high pressure side (ie- on the outlet from the pump) which is optional.

PS- your expansion tank really needs to be on the low pressure side, otherwise the air inside it will just get pushed back down your bleed pipes!

Cheers guy's look's like i've sorted it now, just waiting for payday now so that I can get a nice shiney ally expansion tank off Martin