<VV> 66 Corsa Runs well... for the first 2 minutes, then bogs down

Joe West joew at diveaz.com
Wed May 4 20:17:55 EDT 2005 

Another update.

Further investigation shows that it is a SINGLE carb that wants it's choke
on.  The left Primary carb is the culprit... whatever is going on is related
to the left primary carb.

The saga continues.  Next step in my opinion is to remove the left primary
and see what is going on with it.

Standby for results...


On 5/4/05 3:37 PM, "Joe West" <joew at diveaz.com> wrote:

> Hi Gang,
> 
> Here is an update on the 66 Corsa 140 that likes to run well as long as the
> chokes are on:
> 
> I checked the stones... they are completely clean.
> I replaced the balance tube rubber lines with new ones.
> I tested the distributor vacuum line... it did not leak.
> I tested the vacuum gauge line... it does not leak.
> I tested the metal balance tube... it does not leak.
> I ran with the gas cap loose... no difference.
> I tightened all of the bolts holding on the carbs.
> Accelerator pumps squirt in both primary carbs.
> I checked the choke pull off vacuum lines... all are in good shape.
> Fuel pump is electric... haven't done anything with it yet.
> Checked the PCV orifice... it was unclogged and the appropriate size.
> Tried the unlit propane torch test and it didn't raise the idle speed of the
> car even if I pointed the end of the torch directly into the carb.
> 
> After all the above steps... the car still does not run well unless the
> chokes are almost all the way on.
> 
> One interesting thing however... I decided to block off the carb throat
> completely with my hand to listen for a leak that may become stronger... on
> the left hand primary carb, I heard nothing when I sealed the throat off
> with the palm of my hand... the car just almost died.  However, when I did
> the same test on the right hand side primary carb, I heard what sounded like
> a hissing noise coming from somewhere near the base... I can't for the life
> of me tell where it is coming from.
> 
> Another interesting thing... the factory vacuum gauge reads roughly 8 (not
> sure of units) at idle which is exceptionally low if it is accurate (gauge
> is steady).  My spyder reads close to 25 at idle.
> 
> So... if I put the chokes on she runs like a champ.  Take them off, and she
> bogs down something fierce.  The difference is amazing.
> 
> It looks like I am still headed towards carburetor rebuilding this weekend
> unless anyone has any more ideas.
> 
> Joe
> 
> 
> 
> On 5/3/05 6:42 PM, "Joe West" <joew at diveaz.com> wrote:
> 
>> It looks like regardless of what the issue is; it is highly likely that
>> rebuilding the primary carbs would be a good first step.
>> It just so happens that 4 complete carburetor rebuild kits came with the
>> car... so I'll pull the primaries this weekend and rebuild them and we'll
>> see what happens.
>> 
>> Thanks for the inputs everyone... I'll let you know how this turns out.
>> 
>> Joe
>> 
>> 
>> 
>>> ----- Original Message -----
>>> From: "Joe West" <joew at diveaz.com>
>>> To: "Harry Yarnell" <hyarnell1 at earthlink.net>; "VV"
>>> <virtualvairs at corvair.org>
>>> Sent: Tuesday, May 03, 2005 7:41 PM
>>> Subject: Re: <VV> 66 Corsa Runs well... for the first 2 minutes, then bogs
>>> down
>>> 
>>> 
>>>> Hi Harry,
>>>> 
>>>> If I block the chokes closed so that they are open roughly 3/16-1/4" on
>>> each
>>>> primary carb... the car runs PERFECTLY for as long as I care to drive it.
>>>> 
>>>> If I let the chokes open fully... car runs crappy
>>>> 
>>>> If I close them again... car runs PERFECTLY
>>>> 
>>>> If I open them again... car runs crappy.
>>>> 
>>>> So... whatever this problem is; the car likes to run with the chokes in
>>> the
>>>> almost closed position and runs like a DOG when I allow the chokes to
>>> open.
>>>> 
>>>> Thanks for the idea... it moved us further down the troubleshooting line.
>>>> 
>>>> Joe
>>>> 
>>>> 
>>>> On 5/3/05 3:04 PM, "Harry Yarnell" <hyarnell1 at earthlink.net> wrote:
>>>> 
>>>>> Sounds like fuel. Maybe a partially clogged sock. Or stones. What
>>> happens
>>>>> when you partially close the chokes manually by some mechanical
>>> ingenuity?
>>>>> 
>>>>> Harry Yarnell
>>>>> perryman garage and orphanage
>>>>> perryman, MD
>>>>> hyarnell1 at earthlink.net
>>>>> 
>>>>> ----- Original Message -----
>>>>> From: "Joe West" <joew at diveaz.com>
>>>>> To: "VV" <virtualvairs at corvair.org>
>>>>> Sent: Tuesday, May 03, 2005 5:50 PM
>>>>> Subject: <VV> 66 Corsa Runs well... for the first 2 minutes, then bogs
>>> down
>>>>> 
>>>>> 
>>>>>> Hi,
>>>>>> 
>>>>>> I'm working on my son's new (to him) Corsa and after fixing things like
>>>>> oil
>>>>>> leaks, loose distributor causing incorrect timing and the like... I
>>> feel
>>>>>> like I am close to having it running nicely... here's the final
>>> problem.
>>>>>> 
>>>>>> 
>>>>>> If I start the 140 Corsa cold and drive it... it is AWESOME!  Excellent
>>>>>> power, incredible throttle response... I'm not kidding when I say it is
>>>>>> incredible... for the first 2 minutes.  After it warms up (not even
>>> HOT,
>>>>>> just warm), it starts bogging when I hit the accelerator UNLESS I mash
>>>>> into
>>>>>> the secondaries then the throttle response is better, but NOT NEARLY as
>>>>> good
>>>>>> as when it is cold.
>>>>>> 
>>>>>> My thought is that the primary carbs are running too lean and that with
>>>>> the
>>>>>> chokes on (when cold)... the car runs great.  As soon as the chokes
>>> open
>>>>> up,
>>>>>> it runs lean and bogs down.
>>>>>> 
>>>>>> This is my first late and my first 140 so I'm somewhat shooting in the
>>>>> dark
>>>>>> here.  If anyone has any suggestions or thoughts as to what the problem
>>>>>> could be; please let me know.
>>>>>> 
>>>>>> Kind Regards,
>>>>>> 
>>>>>> 
>>>>>> Joe West
>>>>>> Administrator
>>>>>> http://www.virtualcorvairclub.com
>>>>>> 
>>>>>> 
>>>>>> 
>>>>>> 
>>>>>>  _______________________________________________
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>>>>>>  _______________________________________________
>>>>> 
>>>>> 
>>>>> 
>>>> 
>>>> Joe West
>>>> Administrator
>>>> http://www.virtualcorvairclub.com
>>>> 
>>>> 
>>>> 
>>>> 
>>>>  _______________________________________________
>>>> This message was sent by the VirtualVairs mailing list, all copyrights are
>>> the property
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>>> 
>> 
>> Joe West
>> Administrator
>> http://www.virtualcorvairclub.com
>> 
>> 
>> 
>> 
>>  _______________________________________________
>> This message was sent by the VirtualVairs mailing list, all copyrights are
>> the
>> property
>> of the writer, please attribute properly. For help,
>> mailto:vv-help at corvair.org
>> This list sponsored by the Corvair Society of America,
>> http://www.corvair.org/
>> Post messages to: VirtualVairs at corvair.org
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>>  _______________________________________________
>> 
> 
> Joe West
> Administrator
> http://www.virtualcorvairclub.com
> 
> 
> 
> 
>  _______________________________________________
> This message was sent by the VirtualVairs mailing list, all copyrights are the
> property
> of the writer, please attribute properly. For help, mailto:vv-help at corvair.org
> This list sponsored by the Corvair Society of America, http://www.corvair.org/
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> 

Joe West
Administrator
http://www.virtualcorvairclub.com

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