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Re: Need Help - angry smileyThrottle Control Problem
Posted by: cnicol ()
Date: June 06, 2018 06:58AM

You stated "The pump springs are correct"

To close by themselves, they require the SPECIAL secondary spring.

Just to clarify: Do your secondary (I know they're primary type) carburetors have the SPECIAL spring under the accelerator pump?

Craig N. Coeur d'Alene ID.
66 Black Monza 4dr, 4.2L V8 49k
61 Seamist Jade Rampside 140 PG
60 Monza coupe (sold, sniff sniff)
66 Sprint Corsa convt - First car! Re-purchased 43 years later
2+2 gnatsuM 5691

+17 Tons of parts

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Re: Need Help - angry smileyThrottle Control Problem
Posted by: davemotohead ()
Date: June 06, 2018 07:14AM

RobertC Wrote:
-------------------------------------------------------
> On a stock 140, the secondary throttle plate
> gradually opens to any position based on the
> accelerator pedal. It does not "flip" to
> completely open.
>
> Good luck.
------------------------------------------------------
Actually, the secondary carbs kind of do "Flip open" and they are not gradual like the primary carbs, they go from completely closed to fully open in the last 1/4 of the linkage travel, they work kind of like Vac secondaries on a 4 bl carb.





Email me at: Dave Motohead

1960 4dr sedan caveman car
1961 Rampside (Chetside)
1962 Rampside (Barnside)
1962 Short Rampside (Shortside)
1962 Monza 700 Wagon
1963 Monza 900 coup (General Nader)

-----------------------------------
Rust Free Lancaster Ca

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Re: Need Help - angry smileyThrottle Control Problem
Posted by: BobV66Vair ()
Date: June 06, 2018 11:46AM

I believe that I did use the longer/stronger secondary return springs but I will pull off the tops and verify.

Bob Vinnacombe
Sandy, Oregon
1965 Corsa 140 stock
1966 Monza Soon to be race car
1968 Monza Parts for now

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Re: Need Help - angry smileyThrottle Control Problem
Posted by: davemotohead ()
Date: June 06, 2018 12:28PM

BobV66Vair Wrote:
-------------------------------------------------------
> I believe that I did use the longer/stronger
> secondary return springs but I will pull off the
> tops and verify.
-------------------------------------------------------
The secondary spring is actually shorter but stronger.





Email me at: Dave Motohead

1960 4dr sedan caveman car
1961 Rampside (Chetside)
1962 Rampside (Barnside)
1962 Short Rampside (Shortside)
1962 Monza 700 Wagon
1963 Monza 900 coup (General Nader)

-----------------------------------
Rust Free Lancaster Ca

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Re: Need Help - angry smileyThrottle Control Problem
Posted by: davemotohead ()
Date: June 06, 2018 12:49PM

Primary-secondary-carb-springs



smoking smiley





Email me at: Dave Motohead

1960 4dr sedan caveman car
1961 Rampside (Chetside)
1962 Rampside (Barnside)
1962 Short Rampside (Shortside)
1962 Monza 700 Wagon
1963 Monza 900 coup (General Nader)

-----------------------------------
Rust Free Lancaster Ca



Edited 1 time(s). Last edit at 06/06/2018 12:51PM by MattNall.

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Re: Need Help - angry smileyThrottle Control Problem
Posted by: JimBrandberg ()
Date: June 07, 2018 05:11AM

I know it's not the same but I had trouble getting the secondaries to open on my 390 Holley. If it takes too much pressure to operate, I wondered if the long pusher rod in the tunnel was bowing, it is a pusher rather than a puller. The secondaries would open with a quick stab at the pedal but not with easy pressure. A guy sometimes doesn't want sudden wide open throttle coming off the corner. In frustration, I went to a cable but a guy should be able to get the stock system working. I had already tried solid rather than rubber bushings at the pivots.

I like the return springs that coil on the throttle shaft. Our local Corvair expert Fran Schmit found them at Axman Surplus Store, sent one to Clark's and they had some made.
Sometimes with a stronger spring under the accelerator pump it will not squirt.

I'll stop there, you may be suffering from too much information already. An assistant to operate the throttle while you watch is a good thing and two heads are better than one.

Jim Brandberg
Isanti, MN
CorvairRepair.com

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Re: Need Help - angry smileyThrottle Control Problem
Posted by: RobertC ()
Date: June 07, 2018 09:09AM

JimBrandberg Wrote:
-------------------------------------------------------
>
> I like the return springs that coil on the
> throttle shaft. Our local Corvair expert Fran
> Schmit found them at Axman Surplus Store, sent one
> to Clark's and they had some made.

If the linkage is in good condition and properly set up / aligned, no external / extra springs should be needed.


> Sometimes with a stronger spring under the
> accelerator pump it will not squirt.
>

Why is that? If the linkage is correctly adjusted, the accelerator pump should work. When I finally got my early 65 linkage adjusted (decades ago when I ran first bought the car / the stock 65 140 setup), I never had a problem with the secondary accelerator pump not squirting.

> Jim Brandberg
> Isanti, MN
> CorvairRepair.com

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Re: Need Help - angry smileyThrottle Control Problem
Posted by: RobertC ()
Date: June 07, 2018 09:33AM

BobV66Vair Wrote:
-------------------------------------------------------
> Robert.
> You said the linkage to the secondary's
> was not correct …
> I am not sure I follow why you think the linkage is incorrect.

The ends of the secondary rods have a 90 degree bend that fits in the slotted arms on the cross shaft.

You can put the 90 degree end on either side of the slotted arm.

Only one side will give the correct linkage alignment and free movement of the linkage.

If one or both of the rods are installed incorrectly, I think that linkage may bind and cause a problem with achieving WOT on the "secondaries.

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Re: Need Help - angry smileyThrottle Control Problem
Posted by: BobV66Vair ()
Date: June 07, 2018 10:12AM

Replaced the accelerator pump return springs in the (primary's) acting as secondary's. Now I see that three carbs are fully closed throttle but the RH secondary has a constant drip of fuel down the venture. It's coming right from the venturi cluster. The plate is fully closed and the other three have no fuel dripping at all. I will rebuild that carb again with attention to the passages. I had to order a bunch of gaskets from Clark's. I used all I had messing with them all over the last week. I do not hear any vacuum leaks with my stethoscope and the throttle "hunting idle" seems to be gone now. These carb's have the jets relocated so I hope I don't have to get rid of one. Time and money.

Bob Vinnacombe
Sandy, Oregon
1965 Corsa 140 stock
1966 Monza Soon to be race car
1968 Monza Parts for now

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Re: Need Help - angry smileyThrottle Control Problem
Posted by: Ratt643 ()
Date: June 07, 2018 10:33AM

I would say you have a bad needle and seat, piece of trash not allowing the needle to seat or float level is too high or float is bad.
Sounds like youve made some progress!


1964 Monza Coupe

Maryville, TN
U.S. 129 The"Tail Of The Dragon"

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Re: Need Help - angry smileyThrottle Control Problem
Posted by: Spectre ()
Date: June 07, 2018 10:37AM

Another possible cause of the drip is that the seat is simply not tightened in the carb top. I've had that happen before.

David Clamp


1965 Corsa convertible - 140 4spd/3.55/AM-FM

2013 Mustang GT convertible - 5.0, 6spd auto, Procharger i-1

2003 Miata SE - 6spd manual (wife's toy)

"Victory is mine!" - SG

Norman, OK

Click for Norman, Oklahoma Forecast

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Re: Need Help - angry smileyThrottle Control Problem
Posted by: BobV66Vair ()
Date: June 07, 2018 12:59PM

I took the top off the secondary (PS) and pulled the venture cluster out. I blew everything out and reassembled. No more leaks. Runs somewhat smooth but still doesn't want to idle below 1,500. Fluctuation’s in idle are gone. Ran out of time for today. I'll pick it up Saturday. One can dream.

Bob Vinnacombe
Sandy, Oregon
1965 Corsa 140 stock
1966 Monza Soon to be race car
1968 Monza Parts for now

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Re: Need Help - angry smileyThrottle Control Problem
Posted by: cnicol ()
Date: June 07, 2018 01:06PM

At 1500 RPM, the distributor will be getting into its mechanical advance. You should try temporarily reducing the initial timing until you get the carburetors settled down. Once they're happy (difficult with four primaries) then you can try bringing the timing up a little.

Craig N. Coeur d'Alene ID.
66 Black Monza 4dr, 4.2L V8 49k
61 Seamist Jade Rampside 140 PG
60 Monza coupe (sold, sniff sniff)
66 Sprint Corsa convt - First car! Re-purchased 43 years later
2+2 gnatsuM 5691

+17 Tons of parts

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Re: Need Help - angry smileyThrottle Control Problem
Posted by: BobV66Vair ()
Date: June 07, 2018 01:26PM

Roger that. I'll do that Saturday. Dialysis tomorrow so not much else gets done.

Bob Vinnacombe
Sandy, Oregon
1965 Corsa 140 stock
1966 Monza Soon to be race car
1968 Monza Parts for now

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Re: Need Help - angry smileyThrottle Control Problem
Posted by: thewolfe ()
Date: June 07, 2018 01:27PM

How far out from seated are the mix screws?

Nate Wolfe
Portland OR
65 Corsa 180

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Re: Need Help - angry smileyThrottle Control Problem
Posted by: RobertC ()
Date: June 07, 2018 08:55PM

Curious?

What size jets did you put in the carbs?

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Re: Need Help - angry smileyThrottle Control Problem
Posted by: BobV66Vair ()
Date: June 07, 2018 09:47PM

52 jets in all four. Mixture is now out 3 turns. I ran out of time today so I was happy to get it running well enough to pull into the garage. Its much better now with a lot more power. I still think the secondary's are not opening fully but I need a second person to verify. My wife is too short to get the pedal all the way down hard. The engine has not been rebuilt so it is tired with one cylinder down on compression. Replacement engine coming this Fall.

Bob Vinnacombe
Sandy, Oregon
1965 Corsa 140 stock
1966 Monza Soon to be race car
1968 Monza Parts for now

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Re: Need Help - angry smileyThrottle Control Problem
Posted by: RobertC ()
Date: June 07, 2018 11:37PM

BobV66Vair Wrote:
-------------------------------------------------------
> 52 jets in all four.

Too lean.

The carbs no longer have Power Enrichment Valves.

Using linkage where all 4 butterflies do not open at the same time, I do not know what might work best for you.

I run 55 jets on my 4 primaries (with relocated jets / no PEVs).

> Mixture is now out 3 turns.

Too rich. You have 4 idle circuits versus the original two circuits.

I would expect the exhaust to really smell.

Might try 2 turns out, but it will probably take a few adjustments to find what is best for your setup.

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Re: Need Help - angry smileyThrottle Control Problem
Posted by: RobertC ()
Date: June 08, 2018 12:09AM

BobV66Vair Wrote:
-------------------------------------------------------
> My wife is too short to get the pedal all the way down hard.

Your wife should not have a problem pressing the pedal to the floor.

It is no different (should not be different) from a stock Corvair linkage - a little more pressure would be required if you have a stronger return spring.

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Re: Need Help - angry smileyThrottle Control Problem
Posted by: BobV66Vair ()
Date: June 09, 2018 12:09PM

All situations solved. Throttles work to WOT with pedal down. All return to closed. Mixture may still be off, I need more seat time to know.

Thanks to all who offered assistance.

Bob Vinnacombe
Sandy, Oregon
1965 Corsa 140 stock
1966 Monza Soon to be race car
1968 Monza Parts for now

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