Larry :
I would start by disconnecting the vacuum line(s) to the dizzy, and trying
to get it to run that way. I'm not certain (and my Haynes is unclear on the
subject), but I think a 72 US-emissions model would have only vacuum retard
anyway.
With it disconnected, the ignition timing should move smartly (no visible
delay) to match engine speed. If it doesn't, then the dizzy (or the
mechanical advance mechanism inside it) needs attention.
I can't find an advance curve for your engine, only a static (ie 500 rpm or
less, no vacuum retard or advance) spec of 6 BTDC. Non-emission cars used
13 BTDC.
I did find a factory spec for earlier non-emission GT6, which gives the
mechanical advance at 3000 rpm as being between 10 and 14.2, for a total of
23-27.2 degrees BTDC. The later spec is undoubtedly different, but this is
probably not a bad place to start. And yes, having the ignition retarded by
10 degrees may cause overheating.
One other thought : pull off the hoses to the carb bowl vents and see if
that makes a difference.
Randall
>
>
> took the 72 gt6 for the first drive since rebuild. questions: 1) it is
> getting hot. i pulled the radiator cap and watched the fluid, as
> long as it
> was say > 1500 rpm it flowed very good. at idle about
> 800-1000rpm it was a
> slow dribble. is that normal ? i've dinked with the carbs, they are sync
> pretty good (ear method). idle speed adjusted to 1000rpm about. the big
> question is the timing. i have set it to 13 btdc with engine
> about 3000rpm.
> when i release the throttle i notice that the timing slowly drifts down to
> about 2btd. this is what i am concerned about. it takes about
> 10 seconds for
> it to drift the timing down that low. when the timing drifts
> back to 2btd the
> idle drops below 500rpm and i can't get it to come back up. the
> engine is hot
> and so no matter what i do to the throttle it just eventually
> dies after about
> 5 to 10 seconds. if i wait for the car to cool down a little it
> starts fine.
/// triumphs@autox.team.net mailing list
/// To unsubscribe send a plain text message to majordomo@autox.team.net
/// with nothing in it but
///
/// unsubscribe triumphs
///
/// or try http://www.team.net/cgi-bin/majorcool
|