Subject: [TR] TR6 Vacuum Line Question

From: Jonas Payne <[email-masked]>
Date: Thu, 15 Aug 2013 10:14:35 -0700

I am trying to sort out the Vacuum lines on my recently acquired TR6.

The rear carb has vacuum ports at the top and bottom.  The front has none.
The distributor has a single port.

This doesn't match up with anything I see in either the manual or the moss
catalog.

Jonas Payne
PBR Consulting
702-882-6711

** [email-masked] **

Archive: http://www.team.net/archive

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From: "Randall" <[email-masked]>
Date: Thu, 15 Aug 2013 12:01:49 -0700

> I am trying to sort out the Vacuum lines on my recently acquired TR6.

Is this a restoration, or do you just want it to run good?

> The rear carb has vacuum ports at the top and bottom.  The 

Do you have carb numbers?  Sounds like the rear carb may have been modified,
but it might also be from another car.

The port that has vacuum at idle will be for vacuum retard; the one with
vacuum only with the throttle open will be for advance.  If the carbs are
off the car, then look at where the ports come out relative to the throttle
plate.  If you can see the port opening from the manifold side with the
throttle fully closed, that's a retard port.

> The distributor has a single port.

Advance or retard?  PI TR6 only had advance; later carbed TR6 only have
retard.

It will actually run fine if you just cap both carb lines and leave the
dizzy line open.  If you can hook up the advance, it will reduce fuel
consumption a bit (around 2-3 mpg), but no effect on idle or full power.
The vacuum retard only affects idle; but you may have to turn the idle rpm
down if it was set with the retard active.

Oh, and set the ignition timing to the 'static' value for your year.  The 4
ATDC figure is only for when the retard is connected and active (not
disabled by the TVS).  The books are amazingly unclear (aka flat wrong) on
this point as many of them say to disconnect the vacuum line, but that is
only for an advance vacuum line (which only early carbed TR6 should have).

-- Randall

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From: [email-masked]
Date: Thu, 15 Aug 2013 16:18:28 -0400 (EDT)

Going from memory here but I believe the bottom port is for the vacuum 
retard module. The top one can be used with the vacuum advance module if you had 
one or it can be used for the EGR valve.

Of course things changed from year to year on the TR6 so it would be 
helpful to know what model car you have.

Dave

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From: Jonas Payne <[email-masked]>
Date: Thu, 15 Aug 2013 13:52:10 -0700

Car was dispatched in Feb. 1971, CC62601L.

It was equipped at the dealer with air conditioning.

Jonas Payne
PBR Consulting
702-882-6711

-----Original Message-----
From: [email-masked]
[mailto:[email-masked]] On Behalf Of [email-masked]
Sent: Thursday, August 15, 2013 1:18 PM
To: [email-masked]
Subject: Re: [TR] TR6 Vacuum Line Question

Going from memory here but I believe the bottom port is for the vacuum
retard module. The top one can be used with the vacuum advance module if you
had one or it can be used for the EGR valve.

Of course things changed from year to year on the TR6 so it would be helpful
to know what model car you have.

Dave

In a message dated 8/15/2013 12:15:08 PM Central Daylight Time,
[email-masked] writes: 
> This doesn't match up with anything I see in either the manual or the 
> moss catalog.

Archive: http://www.team.net/archive
http://autox.team.net/mailman/options/triumphs/[email-masked]

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From: [email-masked]
Date: Thu, 15 Aug 2013 17:24:04 -0400 (EDT)

The 71 may or may not have been equipped with a vacuum advance and if it 
was it would not have been connected.  But the 70 TR6 was equipped with both.  
At least that is my recollection.  So there may be some residual fittings 
that were not used but would make retrofitting easier.  My 71 model had both 
advance and retard modules but no port for the advance.  Retrofitting later 
model carbs fixed that problem.

In 1974 the engine was fitted with an EGR valve and that port could be used 
for the vacuum advance (if your distributor was so equipped).

Dave

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From: [email-masked]
Date: Fri, 16 Aug 2013 07:29:51 -0400 (EDT)

The answer, as I like to say, is "it depends."  That was the case on my 
original TR6 carbs but earlier and later model carbs did have both ports 
drilled and tapped (actually not tapped per se but with a tube pressed in).

But using the TR3 as a basis point is problematic.  They had different 
carbs and they didn't have to meet emissions.  Heck, even the TR6's varied 
enough to keep things confusing.

Dave

In a message dated 8/15/2013 5:08:33 PM Central Daylight Time, 
[email-masked] writes: 
> pardon my ignorance.
> if its anything like my TR3 only one of the two holes is live and is 
> tapped.
> no?
>  
>  
> Frank
> 
> 
> From: Jonas Payne <[email-masked]>
> 
>

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From: Frank Fisher <[email-masked]>
Date: Fri, 16 Aug 2013 07:52:41 -0700 (PDT)

thanks Dave
I did know the 3 used SU's and the 6 used Zenith's.
had I been any
place close to home I could have lifted the bonnet on the 6 in the garage and
taken a look.
but that would have taken effort and wait until tomorrow.
Frank
________________________________
 From: "[email-masked]"
<[email-masked]>
To: [email-masked] 
Sent: Friday, August 16,
2013 4:29 AM
Subject: Re: [TR] TR6 Vacuum Line Question

The answer, as I
like to say, is "it depends."  That was the case on my 
original TR6 carbs but
earlier and later model carbs did have both ports 
drilled and tapped
(actually not tapped per se but with a tube pressed in).

But using the TR3 as
a basis point is problematic.  They had different 
carbs and they didn't have
to meet emissions.  Heck, even the TR6's varied 
enough to keep things
confusing.

Dave

In a message dated 8/15/2013 5:08:33 PM Central Daylight
Time, 
[email-masked] writes: 
> if its anything
like my TR3 only one of the two holes is live and is 
-----Original Message-----
> retard module. The top one can be used with
the vacuum advance module if 
> you

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