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TR4/4A Who's right - float height on ZS 175CD?

Zimmycobra

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Okay, I am now confused. The technical paper on rebuilding Zenith Stromberg 175 carbs that is posted on the Buckeye website states that the float height should be 16 to 17mm from the face of the carb body. My Triumph replica shop manual states that the height should 18.5mm.

Who is right??? Thanks.

Zimmy
 
Have a look to see if one states with a gasket installed, that would give you your difference.
I have always done the 5/8 inch back before the metric was used, which in fact is 16 MM.

Wayne
 
Okay, I am now confused. The technical paper on rebuilding Zenith Stromberg 175 carbs that is posted on the Buckeye website states that the float height should be 16 to 17mm from the face of the carb body. My Triumph replica shop manual states that the height should 18.5mm.

Who is right??? Thanks.

Zimmy
I usually take the static setting as a starting point especially if the actual float bowl level can be seen or measured. I believe your carbs are the same as my h6 in that the correct float level can be easily seen with pistons out and is the where the fuel level is just below the top of main jet.

So either setting may require a final tweek.
Tom
 
My TR4 has 175CD carbs and the manual says 18½mm. My other car has 175CD-2 carbs and that manual says 16½mm.

The 175CD-2 is not meant to be adjustable but mine were running a bit rich so I went with a 18½mm setting on those also. Seems better.

Bottom line - it is going to vary based on which 175CD you have and possibly by which year (and emission requirements) the carb was set up for. In any case, as Tom says - may need tweaking.
 
The Buckeye articles are written for the TR6, which use a later version of the ZS carbs and a different float level spec. The correct float level for the CD carbs used on the TR4 (according to the factory manual) is .73" or 18.5 mm.
Berry
 
Thanks everyone. It does seem a bit rich and I will go back to the 18.5 to see if it improves. Thanks.
 
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