HS4 - quick question

[bigjones]

Hi folks,

For the latest HS4 carb, is the float adjustable or is it fixed to give the correct fuel height in the fuel chamber?

I could always take the lid off and find out but would prefer not to - long story. Ha!

Cheers

 

[Hap Waldrop]

There are two floats that came in the HS4 carbs, the earlier carbs had a metal hinge tabs on them, than can be tweaked (bent) to correct float level, the later floats were all plastic, and their float height is adjusted with shims under the needle and seat valve. You could have either floats depending on if thay have been rebuilt, you can either style float new today, or get shimm, I recommend Joe Curto, www.joecurto.com for quality SU parts.

 

[bigjones]

Oh, OK, that explains it - many thanks Hap.

 

[DNK]

Or you can do this

 

[bigjones]

Phut!

I'll race against that with my set up any day of the week:

After I've done some fine tuning, that is.

OK, I took out the piston and turned on the electric fuel pump. You can just see the level of the fuel:

Prolly a millimeter or two below the top. Good enough?

I took off the lid and could easily slide a 3/16" drill bit between upturned lid and float, but not a 1/4". Measured the gap with feeler gauges - 0.235", that is seven and a half thirty seconds (7.5/32").
This is a brand new HS4 I got from Burlen in the UK. I did not see any shims under the needle valve. Any thoughts?

Cheers!

Spec calls for 1/8 to 3/16"

 

[Hap Waldrop]

Joe Curto, has shims for the needle seat valves, www.joecurto.com

 

[bigjones]

Hap,

Thanks for the link - I'll definitely get in touch with Joe when I need some SU parts.

My point was the gap is too big. IF there was a shim there, I could remove it in order to lower the clearance from 7.5/32 to something between 1/8 and 3/16".

Right now it looks like I'm SOL.

Cheers