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hi idle

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zimmy

zimmy

Jedi Knight
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warmed up the car, runs at 52lbs idle and goes up to 73lbs approximately when revved....very smooth runnin at higher rpms like 3500, my broken gas needle doesnt even giggle..smoooth /ubbthreads/images/graemlins/thumbsup.gif
my problem is my idle stays between 1200 and 1500...i prefer 800 to 1000....my idle screw is all the way out...
when i cut the motor i even had a second of run on...never happened before....
how can i get my idle down eh? ..zimmy
 
retard your timing a tad or two. if it is runing on, it may be a little to far advanced.



mark
 
i have MM oil (4oz) in my car right now...
could this affect it and would an oil change
maybe do something? 20-50 castrol syntech blend
my emmissions are removed except for the tube going to the carbs on both sides.....the end is currently plugged...
my carbs are fairly close..they are a little sloppy in the throttle though...meaning more air IN.....hmmmm
 
Check the timing, and BTW, which carbs do you have on this? If SU's of the period, they have the "poppet valves" on the throttle plates?

The oil ain't a big factor, don't worry over that. What "octane" gas are ya running?
 
With worn throttle shafts it is virtually impossible to get the car to idle down. It also makes it hard to set the mixture using the lift the piston method. You may be able to get away with just replacing the shafts and not rebushing the body. There have also been some creative solutions to seal the ends of the shafts.
 
IIRC, Curto sold a variety of "oversize" shafts at some point. If the bushings aren't too "wallowed out" that may be a good solution. Still need to be reamed to dress 'em up, but better than going with a rebush.
 
i have HS2 1974 ....there is an oversized shaft in the victoria british...is it for replacing worn ones like this........
 
Yep in some cases, they also sell a sleave to go with a new shaft or the old one if it is not worn.

Think I would check with my machine shop and see if they could fit the sleeve and I would have a new shaft that was tight forever.
 
You can use some carb cleaner or WD40 to see where your vacuum leaks might be. If it is around the butterfly shaft, spraying either in those locations should change your idle. I don't know much about HS2's but I would check the timing first. You may have to set it statically for now since you can't get the idle down. Also, Zenith carbs have a "deceleration valve" that will cause the same symptoms but not sure if HS2's have the same affliction. Mostly just grasping at straws here...If you know that the butterfly shafts are sloppy, that is probably where I would start but you can verify that with a little carb clearner.
JC
 
Or about anything in a spray-bottle. Likely you don't have the "poppet-valves" in your throttle plates in HS2's. Go with JC's suggestion: static set the timing first, check all dizzy function/condition while you're there. Once that's established you can start fussin' the carbs. I'd go so far as to suggest R&R the beasties and give 'em a good thorough cleaning and going thru. "Couldn't hurt" and you'll have 'em in-hand to check shaft fit, throttle closed position, etc. All the things you can only guess at now.
 
Actually, a '72 midget with emissions would have poppet-valves. But, I agree with giving the carbs a going over.
 
Oh, and you can get new standard size shafts and steel inserts. You will need a machine shop to properly bore the carb bodies to accept the inserts... and not all machine shops will take on this task.
 
If it does have the valves and the rest of the emissions gear is gone, I'd suggest soldering those things shut. They're the likely cause of both symptoms if the timing is correct. The hair-like springs weaken or break, the centering hole gets worn, they just LEAK... and cap the tubes that "Y" together, right at the carbs: less stuff to leak air past.
 
The tubes that Y together should be atached to the front timing cover oil separater (if all other emissions equipment has been removed).
 
I was goin' for the "no leaks" approach first, Trev. Tighten it all down as well as possible.

Wouldn't the case just vented to atmosphere send the idle up some? I didn't consider that. ack.

EDIT: And now I'm recalling some sort of "restrictor" or filter thingie in that line, too... is that right, or am I recalling some unrelated line... I hate gettin' old.
 
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