<VV> Timing

Chris C, Warwick RI ricorvair at cox.net
Wed Mar 29 12:29:30 EST 2006


Thanks much for your help.

I put my hand over each carb.  Each had heavy suction, enough to leave an 
impression on my hand.

Driver side, engine slowed way down, nearly stalled.  Can hear what sounds 
like the carb pumping.
Passenger side, engine slowed down slightly.  No sounds, but the exhaust is 
on that side.

Both sides of motor get warm.

During warm up lightly on gas, it almost felt like it got stuck at a point, 
then surged.

Did re-adjust the lifters.  Light tapping on drivers side.  Backed each one 
out till it clacked, then down till it quiets down.  Once done 1/4 turn each.

Now the other side has a light tap, that comes and goes.  This is the side 
that did not slow down.  Compression #;s are good.

When I checked the filter stones, the drivers side almost no gas came out, 
passenger side considerably more.

I can either go to a Bay State meeting, or have several hours to play with 
the car.  Assuming the wife completes her responsibilities for the PTO meeting


At 01:13 PM 3/28/2006, you wrote:
>If nothing else changed, then either suspect a malfunction centrif advance 
>in the dist or a fuel/carb problem.
>
>Bill
>
>Chris C, Warwick RI wrote:
>
>>It has been fine for 6 years, got kind of crappy end of last season.
>>
>>
>>At 08:23 AM 3/28/2006, you wrote:
>>
>>>Timing is very important, but also tagged to your distributor. What are 
>>>the numbers on your dizzy? We need to make sure you have the right one 
>>>to begin with...
>>>
>>>The timing is when the spark plug fires. Too soon and the mixture isn't 
>>>compressed enough (an the piston is still on the upward stroke) so power 
>>>suffers greatly. Too late and the mixture may preignite 9detonation) 
>>>before the spark happens.. very damaging because of the uncontrolled 
>>>burn and concentration at "hot spots"
>>>
>>>On a Corvair engine you want about 10 BTDC at idle (so you're in the 
>>>ballpark) but more importantly about 30-32 degrees of total advance at 
>>>high rpms. The different distributors advance at different rates and to 
>>>different maximums (the "advance curve"), so it's critical to know which 
>>>distributor you have. If you have an advance timing gun you can test for 
>>>that directly...with a normal gun you need to mark the pulley at the 30 
>>>degree point. When revving up the engine in neutral, you should see the 
>>>advance pull smoothly from wherever you have it at idle to the 30 degree 
>>>point (by about 4000 rpm).
>>>
>>>For the time being, disconnect and plug the vacuum advance altogether. 
>>>That takes it out of the equation. Only add it back in once you have the 
>>>car running satisfactorily.
>>>
>>>Also, I'm still not sure it's not carbs. With the engine idling and the 
>>>breather assembly off, carefully place the palm of your hand over the 
>>>carb throat one at a time. If it stumbles and/or dies, the carb is 
>>>working correctly. If it speeds up or stumbles just a bit then 
>>>stabilizes, you have carb issues.
>>>
>>>Do not reuse carb stones. Toss them...
>>>
>>>What plugs are you using? Are your carbs properly synced? Did you check 
>>>the advance springs (under the points plate) for free operation?
>>>
>>>Not a basic question at all; the majority of Corvair owners are driving 
>>>around in poorly driving cars... ;-) Your car should take off a bit 
>>>slowly but storm to 40mph in first gear after the first 15-20 feet.
>>>
>>>Bill
>>>
>>>Chris C, Warwick RI wrote:
>>>
>>>>I know this is a basic question, but I can not find my basics 
>>>>manual...damn spring cleaning.
>>>>
>>>>What effect does the timing have on performance.  Right now I am at 12 
>>>>and the car isn't quite right. 16-26 the acceleration lags.  Some speed 
>>>>demon may rear end me because 0-15 is normal, but that brief range is slow.
>>>>
>>>>I will try changing it and see what it does, but interested in the 
>>>>theory behind it.
>>>>
>>>>
>>>>My car had snowman acceleration (sno balls) from a start, but would 
>>>>stay at speed ok.  Real struggle getting it to go up a hill.
>>>>
>>>>Started and once warmed up idled fine.  Its a 65 110/pg.
>>>>
>>>>Cleaned fuel tank, replaced inline filter, and filter stones got a 
>>>>little better.  Can old stones be cleaned out, or do I just toss 
>>>>them.  Cheap corvair guy, hate throwing anything out.
>>>>
>>>>Dwell was jumping around at idle.  Replaced condenser, cap, coil, 
>>>>points, points plate.  Now it idles smooth, 0-15 fine, 16-25 it boggs a 
>>>>little, and ok from 26-35 (the fastest I can legally go around town).
>>>>
>>>>The old points plate seemed to get stuck 1/2 threw the movement (when 
>>>>removed).
>>>>
>>>>Dwell is now a constant 32, dips a little at acceleration.  Idles about 
>>>>650 in gear, smooth.  A little concerned the replacement condenser was 
>>>>1/8 inch longer than the one I took out.  If I use a mityvac to move 
>>>>the vac advance, it moves fairly evenly, but does stops before it 
>>>>reaches the high side.
>>>>
>>>>The timing i
>>>>
>>>>
>>>>
>>>>_______________________________________________
>>>>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
>>>>Change your options: 
>>>>http://www.vv.corvair.org/mailman/options/virtualvairs 
>>>>_______________________________________________
>>>
>>>
>>>--
>>>No virus found in this outgoing message.
>>>Checked by AVG Free Edition.
>>>Version: 7.1.385 / Virus Database: 268.3.2/294 - Release Date: 3/27/2006
>>
>>
>>
>
>
>--
>No virus found in this outgoing message.
>Checked by AVG Free Edition.
>Version: 7.1.385 / Virus Database: 268.3.2/294 - Release Date: 3/27/2006
>




More information about the VirtualVairs mailing list