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-   -   85 12A - RB Holley, no idle (https://www.rx7club.com/1st-generation-specific-1979-1985-18/85-12a-rb-holley-no-idle-1049098/)

Turbo00 10-17-13 08:32 AM

85 12A - RB Holley, no idle
 
Car is an 85, 12A w/ RB prepped Holley 4160/465, RB header-back, all else stock on the engine.

I finally got to the point in my resto where it's time to move the car and prep for paint. Got the holley installed, and while I can keep it running by manipulating the throttle, I have zero fuel entering w/o some degree of throttle input. Thought maybe I had a blockage (carb has been sitting for a few years), so I rebuilt/cleaned, still zero fuel at idle.

I'm a little worried that theres not enough vacuum to pull any fuel, and I know that I'd be better off with a weber/dellorto setup, which is where'd I'd like to end up, but for now I'd like to at least be able to start it and move it around before the snow flies. Any help would be very much appreciated!

Chris

wankel=awesome 10-17-13 01:36 PM


Originally Posted by Turbo00 (Post 11600176)
Car is an 85, 12A w/ RB prepped Holley 4160/465, RB header-back, all else stock on the engine.

I finally got to the point in my resto where it's time to move the car and prep for paint. Got the holley installed, and while I can keep it running by manipulating the throttle, I have zero fuel entering w/o some degree of throttle input. Thought maybe I had a blockage (carb has been sitting for a few years), so I rebuilt/cleaned, still zero fuel at idle.

I'm a little worried that theres not enough vacuum to pull any fuel, and I know that I'd be better off with a weber/dellorto setup, which is where'd I'd like to end up, but for now I'd like to at least be able to start it and move it around before the snow flies. Any help would be very much appreciated!

Chris

Well if you look at the RB metering block its pretty easy to see that part
throttle emulsions are a joke. They mod it for single stage emulsions, like a lawnmower carb. I had similar issues, but mine were exaggerated by a tiny crack in the main body somewhere.

wankel=awesome 10-17-13 06:00 PM


Originally Posted by wankel=awesome (Post 11600445)
Well if you look at the RB metering block its pretty easy to see that part
throttle emulsions are a joke. They mod it for single stage emulsions, like a lawnmower carb. I had similar issues, but mine were exaggerated by a tiny crack in the main body somewhere.

Also, turn both idle screws out 2 complete turns, then see what happens. Baseplate could be closed too far...

ghost1000 10-20-13 08:49 PM

I'm the best with holleys.

First check your idle set screw.
Open idle crews 1turn from closed position.
If this fails check gasket fitment.
Spray wd40 through metering block and main body. This is not to clean but to help trace pasage openings. Make sure all vacuum ports are capped.
Check for vacuum leaks.

Pm me if u need help

wankel=awesome 10-21-13 06:16 AM


Originally Posted by ghost1000 (Post 11603012)
I'm the best with holleys.

First check your idle set screw.
Open idle crews 1turn from closed position.
If this fails check gasket fitment.
Spray wd40 through metering block and main body. This is not to clean but to help trace pasage openings. Make sure all vacuum ports are capped.
Check for vacuum leaks.

Pm me if u need help

Holley throttle shafts are a calibrated leak.... Spraying WD40 around them would be sorta silly, as you WILL find a vac leak around the shafts! (working as intended....)

ghost1000 10-21-13 02:05 PM

Take the carb off the car.
Take the metering blocks off the carb.
Take the jets and power valve out.
Spray WD-40 into holes to trace passages.
This will help you find a blockage.
Do this with the gaskets in place.

Replace the power valve.

Turbo00 10-22-13 10:06 AM

Thanks for the ideas guys, I'll check a few things towards the end of the week.

I'm 99% confident the metering block is clear, and I replaced the power valve during the rebuild. If I still can't get any fuel after messing around with it on the car, I'll pull it back off and take another look.


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