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Thread size on Holley (Howell) TBI idle screw [message #180381] Wed, 15 August 2012 14:17 Go to next message
RF_Burns is currently offline  RF_Burns   Canada
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I guessing I did the idle setup so many times before I got the EBL that my idle adjust screw is loose. I keep needing to re-adjust it because it backs off and the IAC needs to open further and further... I'm up to the high 20's count again now so I need to reset it again.

I'd like to put a jam screw against it but I can't find one that fits.

Looks like a fine thread 3/8" but I'm thinking its maybe a metric?

Thanks

Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.
1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that

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Re: Thread size on Holley (Howell) TBI idle screw [message #180399 is a reply to message #180381] Wed, 15 August 2012 16:20 Go to previous messageGo to next message
George Beckman is currently offline  George Beckman   United States
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rf_burns wrote on Wed, 15 August 2012 12:17

I guessing I did the idle setup so many times before I got the EBL that my idle adjust screw is loose. I keep needing to re-adjust it because it backs off and the IAC needs to open further and further... I'm up to the high 20's count again now so I need to reset it again.

I'd like to put a jam screw against it but I can't find one that fits.

Looks like a fine thread 3/8" but I'm thinking its maybe a metric?

Thanks



Could you find a spring, like the idle air adjustment on carbs that would help hold it.


'74 Eleganza, SE, Howell + EBL
Best Wishes,
George

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Re: Thread size on Holley (Howell) TBI idle screw [message #180404 is a reply to message #180381] Wed, 15 August 2012 17:19 Go to previous messageGo to next message
RF_Burns is currently offline  RF_Burns   Canada
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George,
Mine is recessed so there is no place to put a spring.

Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.
1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that

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Re: Thread size on Holley (Howell) TBI idle screw [message #180432 is a reply to message #180381] Wed, 15 August 2012 20:50 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
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rf_burns wrote on Wed, 15 August 2012 15:17

I guessing I did the idle setup so many times before I got the EBL that my idle adjust screw is loose. I keep needing to re-adjust it because it backs off and the IAC needs to open further and further... I'm up to the high 20's count again now so I need to reset it again.

I'd like to put a jam screw against it but I can't find one that fits.

Looks like a fine thread 3/8" but I'm thinking its maybe a metric?

Thanks


Bruce,

Given the time period, it is probably metric.
But, before you work too hard, wrap a turn of teflon tape around the screw. That works lots of times.

Matt

Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit

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Re: Thread size on Holley (Howell) TBI idle screw [message #180459 is a reply to message #180381] Thu, 16 August 2012 05:38 Go to previous message
RF_Burns is currently offline  RF_Burns   Canada
Messages: 2277
Registered: June 2008
Location: S. Ontario, Canada
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Matt, thanks for that idea, I shall give it a try.

Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.
1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that

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