Gravity

[Jasonking]

Hiya all, would an HS2 run/operate correctly with a gravity fed fuel supply? Or do its fuel pump need to be running supplying the juice?

[Peter Laidler]

It'd work perfectly well with a gravity fed system. But it would depend on the HEIGHT that it was being fed from! That's because the gravity fed fuel would fill the fuel bowl until the float stopped the flow. If the gravity feed was too high......... Let's not bother because realistically you wouldn't achieve the height that would overcome the fuel bowl float and if it did, it'd vent away anyway.

As a matter of probably little interest, gravity feeding the carb is a good way of starting the engine using a fuel filled pop bottle and bit of hose when the fuel lines.pump or even the tank isn't fitted

[Jasonking]

Thought it would work just wanted confirmation with an SU, okey dokey back to square one with the mini not starting again I’m totally at a loss as to why it won’t go…….?

[Peter Laidler]

Don't despair Jason. Very basically, ou only need three things to get it to start. Some petrol, a bit of air and something to set it on fire, like a spark at the right moment - in measured quantities of course.

If you are trying the gravity feed system, don't forget that the bottle or can must be open at the other end so that the fuel isn't creating its own vacuum within the closed bottle. Been there and done just that just 2 weeks ago with my stubborn lawn mower!!!!!

[Jasonking]

Think the key phrase is, spark at the right moment! It’s not even trying to fire I’m stumped again!

[floormanager]

I've ran up S engines on gravity-fed fuel (an old Sufolk punch lawnmower fuel tank). Reason to check it can run and no major leaks before install.

[Oneball]

Have you checked you’ve got compression again?

[Jasonking]

Doubt if there’s much compression need engine to run to heat seal head gasket

[iain1967s]

Distributor out 180° ?

[Fanfaniracing]

Hej Jason!

Do you have any workshop manual at hand?

Check that your distributor drive is on the right place and then go step by step.

It's like peter and ian said, when all the three things work tougher your engine will run.

I have workshop manuals here, but unfortunately only in German...

[minstix]

If petrol is getting into the float chamber/chambers and it's not starting you'll probably be able to smell it. Otherwise, you could remove the three screws on the float chamber/chambers and see if it/they are full of petrol. If the gasket was fitted dry it should survive without being damaged. Otherwise you might have to replace it (Mini Spares do good replacements that ar slightly sticky and seal well and can be removed and replaced).

Also, timing is crucial. Has the distributor been messed with at all? It's possible to set up the distributor to be 180 degrees out compared to the flywheel. There's a very good description of how to check it and get it right in the old Haynes manual. Also, have the HT leads possibly changed their positions? It should fire spark plugs in the order 1,3,4,2.

Steve

[Oneball]

Doubt if there’s much compression need engine to run to heat seal head gasket

The coating on the head gasket doesn’t really help with compression, if the fire rings aren’t sealing the moment you torque the head bolts you’ve got an issue somewhere.

I saw a picture of your failed head gasket and it looks to me that there maybe something wrong with the trueness of your head or block or a clamping issue with the head studs.