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SU HS4

There have been quite a few procedures done to my '82 Mini which I forgot to document on digital camera. Let's back track a bit...

Safety first!

 Brake lines were bled and refilled with fresh fluid. Brake shoes were thick, master and wheel cylinders were working fine so I just cleaned all the drums, adjusted  the shoes (one full wheel turn) and made sure no air got stuck in the hydraulic line.

Pedal pressure was good for a non-servo brake system and the car maintained a straight line on hard braking.


 My dad's initial enthusiasm to test drive the car was curbed upon hearing rattles. All the swivel joints were on their last shims and duly replaced following this preparation procedure from Mini Addicts. The shot steering rack was another major rattle contributor. Haynes manual at hand, this site and the assistance of a mechanic, Gilbert, who never handled a Mini in his life; we managed to get a brand new steering rack in place in less than four hours in my drive way.

The car is already fitted with Hi-Lo adjustable suspension, coil springs + Koni Classic shock absorbers which lowered the ride height below practical road use in Manila. Standard length KYBs replaced the Konis and Hi-Los adjusted to original ride height.

Brakes, steering and suspension sorted, engine is next....

Radiator removed, cleaned, cooling system drained until there were no signs of rust colored liquid circulating from the water jackets.

I thought the engine was always running too rich and I could not adjust the carburettor for consistent mixture.


 To my dismay the throttle body had a crack, probably caused by an ill-fitting/home made cardboard gasket and over tightening the two intake manifold mounting bolts.


Epoxy steel + DIY gaskets from true gasket material tied me over for a few months....


...meanwhile I scouted eBay and snagged this older SU HS4 for $30. It probably came from a junked Austin America (Austin/Morris/MG 1100/1300). I also ordered an SU repair kit, needle, float, gaskets and etc.


I stripped/cleaned the eBay acquired HS4 and combined the best parts available from both units.

Overhauled SU HS4 to the left ready for installation

I reverted to a non-Waxstat type jet upon confirming with Seven Enterprises that it offers slightly more efficient performance. Since my 998cc engine came with an LCB exhaust, I fitted a new AAU needle. Easily done since it has the self-centering/spring loaded type piston.

The engine started on the first crank but it started to rain ;(
Fine tuning of mixture and other minor adjustments saved for another day....

Icing on the cake - K&N filter for the stock air-box ;)

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