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vacuum advance hose

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CuriousGeorge

Senior Member
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Guys, I found my vacuum advance hose off and want to make sure I connect it properly--does it to to the hose comming out of the bottom of the carb closest to the firewall? By the way, the PO has this hose (tube) plugged...
 
The tube goes to the front carb
Dan
 
Pretty sure its vacuum retard, and that, as tinman already stated, should go to the front of the carburetor. Not real sure why the hole would be plugged, unless you have electronic ignition.
 
I don't believe a 72 TR6 had vacuum advance; only vacuum retard. The retard line should go from the distributor to the Thermal Vacuum Switch in the top radiator hose; and then from there to the fitting underneath the rear carb.
 
Yep, that's the vacuum retard; not totally necessary but doesn't hurt anything either.
Mines a 73 TR6 and the vacuum source is on the bottom of the rear carb, so maybe they changed the location or it's one of those random Triumph things.
 
Just a ? Does the vacuum source know whether it's for advance or retard? Seems to me where the vacuum line attaches to the dizzy is the important question. Or did I miss something.

Jim
 
bgbassplyr said:
Just a ? Does the vacuum source know whether it's for advance or retard? Seems to me where the vacuum line attaches to the dizzy is the important question. Or did I miss something.

Jim
Click to expand...
Vacuum levels vary under different circumstances at different locations so the attachment point will be measureing something slightly different and giving a different signal to the advance/retard.
 
CuriousGeorge said:
It seems like my 6 runs better with this tube disconnected...what's the deal?
Click to expand...

Maybe the spark timing is off?

What do you mean by 'runs better'? Idle, High RPM, power, everything?
 
bgbassplyr said:
Just a ? Does the vacuum source know whether it's for advance or retard?
Click to expand...
Yup. It's "ported" vacuum, meaning it's blocked off for certain throttle positions. An advance port is blocked at idle (so no advance at idle); while a retard port is unblocked only at idle (so vacuum retard only at idle).

Mixing them up can cause a VERY poor running engine.
 
Pete, you were correct. I adjusted the points relative to the rotation the vacuum effects and presto! Running great with the hose connected! Thank you all once again.
 
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