One Idle, Two Idle, Red Idle, Blue Idle

[Webb Sledge]

I took a look at what the idle speed for my TR6 should be today, and it showed ~800rpm, which sounds right. But then it listed the "fast idle" at 1300rpm, which I have no idea what is. Can someone explain?

Also, I have adjusted the idle speed via the idle screw on the carb as far down as it will go, and it still idles at 1300 when warm. When it's cold it'll do about 800, and then rises over a period of 5 or 10 minutes. I'm suspecting the mixture is wrong, which I really don't want to mess with. The result of my non-existant engine tuning skills plus the twin Strombergs won't be pretty.

 

[mailbox]

"Fast idle" is the idle speed with the choke fully engaged. Most carbs have a seperate idle screw for this. I don't know anything about the setup of Stromburgs, but good luck anyway. /ubbthreads/images/graemlins/grin.gif

 

[trrdster2000]

Hi Webb, are you sure the choke is completely off, some I have seen have the coke cable to tight and it never fully goes off. There is a little clip on the top left side of each carb that holds the outer cable, un chip both of these after the car has warned up, watch the clip doesn't go boing out in the yard, follow the inside cable to the cam at the bottom of the of the carb, that is were you make the choke adjustment. Push the cam all the way down and see if the little screw is touching the level for the butterfly, if so , undo the nut securing the screw and turn it off. Check both carbs for this. Without a vacuum reading tool it will be very hard if not impossible to set the carbs up properly. The little screw you are adjusting is the fast idle and needs to be done when the engine is cold, you will have to play with it abit since you are doing it for the first time. Now put the clip back on the choke outer cable before you try to adjust and leave abit of slack in the inter cable. This helps to make sure the choke is fully off when you push it back in from the inside of the car. Wayne

 

[Webb Sledge]

Thanks, though I'm not exactly sure what you're talking about, because I'm a visual person. I'm sure I can figure it out by looking at it tomorrow (it's dark out now, and my car is void of a garage).

 

[mailbox]

Webb Sledge,
What he is trying to say is the choke may not be fully opening when you push your choke cable in. Take off your air cleaner, push your choke cable all the way in, and look to see if the choke butterfly is in the full open position. If not, this is your problem. This is a fairly simple fix that doesn't involve adjusting the carbs. Let us know how it comes out. /ubbthreads/images/graemlins/savewave.gif

 

[Webb Sledge]

Thanks mailbox, that wording helped me a lot. I'll check that out tomorrow.

 

[Rick O.]

The procedure for adjusting the choke ("starter boxes") is in Bentley/Haynes. You use a 1/8 drill bit shank to offset the curved choke lever from its stop. From that position, you turn the hex head screw on the throttle linkage until is just touches the the choke lever. That's it.

As far as a creeping idle with warm up, I think you should check for vacuum leaks on the throttle shafts (carb cleaner spray, dropped idle). It is possible your temp compensators are out of adjustment/lost seals.

 

[Webb Sledge]

My Strombergs don't seem to have butterflies. They have what looks like slides, that open and close in a verticle motion, and they only move (with the throttle) when the car is on. I can move them with my finger with the car off. When I move the choke, those "slides" move a little bit, but no more than 1/8th of an inch, which by looking at the choke linkage is what they're supposed to do. The lever which makes them move is connected to the choke cable, and when you push the cable back in, it come completely away from the throttle lever.

 

[mailbox]

Sorry,dude. /ubbthreads/images/graemlins/blush.gif Like I said, I'm not very familiar with side draft carbs. /ubbthreads/images/graemlins/confused.gif That setup is more for a domestic downdraft carb. Hope you get it working. /ubbthreads/images/graemlins/grin.gif

 

[Webb Sledge]

Meh, forget it. It'll run ok 'til January when we pull the engine, then Webers'll go on they'll solve all my problems.

 

[Bugeye58]

Webb, push one of the "slides" all the way up, and look inside. You will see the brass colored throttle plate, commonly referred to as the "butterfly".
Jeff

 

[Rick O.]

[ QUOTE ]
then Webers'll go on they'll solve all my problems.

[/ QUOTE ]
Not necessarily. Weber carbs require much more tweaking than your current setup. If you are not familiar with them, I strongly urge you to find someone who is.

 

[UltimateQuestion]

[ QUOTE ]
then Webers'll go on they'll solve all my problems.

[/ QUOTE ]
Or cause a whole new set of problems /ubbthreads/images/graemlins/devilgrin.gif As Rick said, Webbers are particularily finicky and need a whole lot of adjustment. I once put a very simple "bolt-on conversion" two-barrel downdraft Webber on a Ford Escort and I ended up having to take it to a specialist to get it dialed-in.

 

[Webb Sledge]

I don't know. I've talked to 3 different people, including my boss Joe, who say they put Webers on and didn't hardly have to do anything to them, and loved them. /ubbthreads/images/graemlins/confused.gif The reason for this is that Strombergs are atmospheric dependent, meaning you can get them tuned well on a warm sunny day, and then they run like crap the next rainy, humid day, whereas Webers are not atmospheric dependent.