SU HS4

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Rust bucket
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SU HS4

Post by Rust bucket »

Soon I will be connecting up the SU HS4 on my car, I think the top one on the float bowl is fuel in?, and the other a vent?, also do I block off the other one which is at forty five degrees or connect to something.
bmcecosse
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Re: SU HS4

Post by bmcecosse »

Don't block off anything...unless the carb is part of a twin-set ? Make SURE the float bowl is dead vertical when you have it fitted. What manifold are you using ??
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simmitc
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Re: SU HS4

Post by simmitc »

Yes, the pipe on top of the float chamber is the fuel line from the pump. Where is the other pipe? You might have a small one on the same side as the float chamber - that is for the vacuum pipe to the distributor; and one on the opposite side to the float chamber, which is connected to the crankcase breather to suck fumes back into the engine.
Rust bucket
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Re: SU HS4

Post by Rust bucket »

Manifold is a water heated alloy copy of something, only I wasn't going to connect up the manifold, carb has a tiny pipe for distributor as well as this other pipe, I'll see if I can get a picture up.
Rust bucket
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Re: SU HS4

Post by Rust bucket »

This is a new old stock carb I got of ebay some time ago, has a ADE needle which I'm going too attempt to wittle down to the profile of an AAA / AAU, could the carb be part of twin carb set?.[frame]Image[/frame]
bmcecosse
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Re: SU HS4

Post by bmcecosse »

No it looks fine as long as the float bowl is vertical. The copper pipe is the breather pipe - connect to rocker cover. The upper brass pipe with 'bell' end is the fuel inlet - the other is the breather/overflow. Put a rubber hose on it and lead below - although I usually do a 'swan neck' to stop any unnecessary fuel loss.
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Rust bucket
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Re: SU HS4

Post by Rust bucket »

Okay, thanks very much for that.
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