<VV> Re: hesitation on acceleration...

Larry Forman Larry@Forman.net
Tue, 06 Apr 2004 21:01:21 -0700


At 10:22 PM 4/5/2004 -0500, werp knarly wrote:
>either i missed it or i didnt get any replies to this...
>Thanks!
>Joe,
>From: werp knarly
>   To: virtualvairs@corvair.org
>   Sent: Sunday, April 04, 2004 1:00 PM
>   Subject: hesitation on acceleration...
>
>   my 67 110 pg tends to hesitate when trying to accelerate from a quick
>deceleration...
>   seems to be short on fuel.. if I pump on the accelerator it takes right
>off..
>   any ideas on what i should look at?
>   Thanks!
>   Joe

Hi Joe,
I missed it also, so I think no one replied.   My thoughts are that you 
need to perform the basics and ensure they are there before going directly 
to the symptoms.  It makes no sense to look at symptoms if the basic engine 
has "issues".  Since you did not mention what had been done before, I am 
starting at square one.  No flame intended at all, just my diagnostic 
process. Here are some ideas and questions:

1. Have you performed a cylinder compression check?  This is THE basic 
starting place for any engine diagnostic.  You will always have some 
"issues" if you have one or more low cylinders.
2. Have you performed a tune-up?  What did the plugs "read" when you 
replaced them?  This means new plugs (possibly Bosch 7502 Super Coppers aka 
W8AC), 8 mm silicone wires (maybe Seths?), brass distributor cap and rotor, 
new points and condensor or run with an Ignitor.  Stock gap for 
starters.  Do you run with the stock coil, if so, has it EVER been 
replaced?  If never replaced, replace it regardless.  I like Flamethrowers, 
but others are fine.  Check the mechanical advance for proper direction and 
freedom?  Checked the vacuum advance that it works and when it comes on, at 
approximately 9-10 inches of vacuum and NOT the 4-6 as is very 
typical?  Can be fixed by banging on the nipple end with a deep 9/16 inch 
and 5/8 inch socket until it works properly.
3. Do you have good accelerator squirt on both carbs?  Have you recently 
rebuilt them?  If not, do so.  This will eliminate issues like plugged 
inlet filters, etc.
4. Have you checked the engine manifold vacuum?  Is it steady or bounces 
like the valves need adjusting?
5. Replaced the cross over vacuum hoses that are frequently leaky from 
getting brittle?
6. Checked the carbs for balance and the linkage for any slop.  It is quite 
possible you have one carb doing all the work.

WOW, I am tired!  If you have done all this, THEN we can really get to 
work!  LOL.

Larry