Martin and Joe --
I had the same problem in my GT6+. It was caused by the bypass valve
crapping out. If this is your problem, there are two cures: The
factory-approved and expensive solution is to replace the valve. The DPO,
cheap solution is to block off the valve. I did so, for example, by (1)
removing the valve; (2) placing a suitably sculpted piece of beer can
remnant over the inlet and outlet holes for the bypass valve; and (3)
reattaching the now useless bypass valve. If you have to pass any kind of
exhaust emission guidelines, the second option may not work. Otherwise,
give it a try. It's cheap. And, at least in my case, it worked. I'm
idling at a very nice 700 rpm now as opposed to the 1200 I couldn't cure
before.
-- Andy (GT6+ in Minnesota)
p.s. I attempted this cure because I read somewhere (where?) that if the
bypass valve stuck open it would cause a high idle. This now elusive source
said that no problems would be encountered if the valve stuck closed. Which
is, of course, what I replicated with my piece of Pig's Eye can.
-----Original Message-----
From: Joe Curry <spitlist@gte.net>
To: M. Secrest <msecrest@erols.com>
Cc: triumphs@autox.team.net <triumphs@autox.team.net>
Date: Saturday, January 02, 1999 5:05 PM
Subject: Re: GT6 carburetors: time to rebuild?
>
>Martin,
>It sounds as if there is air getting into the system somewhere. It's
>most likely around the throttle shafts.
>
>Before spending $350 for someone to rebuild the carbs, I'd recommend
>taking the bodies to someone who can drill out and re-bush the shaft
>channels and replace the throttle shafts with standard size ones.
>
>I had that done to my SU's for about $60.00 not including new shafts.
>
>Regards,
>Joe
>
>M. Secrest wrote:
>>
>> Since I've owned my GT6, about 2 years now, I never have been able to
>> get the carbs to behave quite rightly. The chief problem is that
>> they won't idle correctly -- even with the
>> throttle stops fully out (i.e. the butterflies fully closed), the
>> car still wants to idle high. And now that I've put in electronic
ignition,
>> a header and free flow exhaust, the lowest idle I can achieve is about
>> 1100 rpm, again, with the stops all the way out. As you can imagine,
>> with this setup, the air flow is not balanced, and yes, the butterfly
>> valves are installed correctly.
>>
>> Having said all of that, I'm wondering if it's just time to send the
carbs
>> off to Apple for rebuild. I believe they have about 70K on them; would
>> it be reasonable to expect that the jets have grooves worn in them,
>> causing this high idle? Also, can you SEE such grooves? (The throttle
>> shafts seem O.K., but I suppose these could be letting in air as well.)
>>
>> In any case, before I spend $350 with Apple, I thought
>> I'd conjure up the list spirits for advice here. I'm also sort of
>> wondering if this isn't just the time to think about carbs other
>> than the stock 150's, but I do drive the car on the street, and I'm not
>> eager to encounter smog law hassles.
>>
>> --
>> Martin Secrest
>> 73 GT6
>> 72 TR6
>
>--
>"If you can't excel with talent, triumph with effort."
> -- Dave Weinbaum in National Enquirer
>
>
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