Vacuum Secondaries Not Opening

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Have you tried turning the sensitivity screw on the front of the vacuum pot to see if it may be bottomed out?
This screw will cause the secondaries to open sooner or later in the rpm range.
Clockwise will open later counter clockwise will open sooner.

1477_3.jpg
 
Did you use the paper clip on a road test? (Your secondaries won't open on the driveway.)

Try this...

Ignition off, choke fully open, throttle wide open... open the secondaries manually... the diaphragm should hiss air thru the passage you blew your shop air past... let the diaphragm return... if it slams shut, you have a leak... if it closes slowly, it's good.

.
 
Have you tried turning the sensitivity screw on the front of the vacuum pot to see if it may be bottomed out?
This screw will cause the secondaries to open sooner or later in the rpm range.
Clockwise will open later counter clockwise will open sooner.

1477_3.jpg

Mine doesn't have that adjustment.

Did you use the paper clip on a road test? (Your secondaries won't open on the driveway.)

Try this...

Ignition off, choke fully open, throttle wide open... open the secondaries manually... the diaphragm should hiss air thru the passage you blew your shop air past... let the diaphragm return... if it slams shut, you have a leak... if it closes slowly, it's good.

.

Yep doc, always a road test for vac secondaries. I've tried that test but I'll try it again.

Thanks guys, I really appreciate the help. I discovered an issue with my throttle linkage that's causing it not to open the carb fully currently, so I'll be correcting that. I'm thinking that's the source of the issue. Admin can delete this one and I'll make a new thread if I still have a problem.
 

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