Date: Wed, 22 Oct 2008 11:40:16 -0700
Reply-To: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Subject: Re: Timing vanagon without timing scale, only insturment ?'s
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here's another way to get the timing darn close to perfect.
The engine has to be running decently.........
like decent compression in all cylinders, and idling properly.
( what symptom or reason prompts you to want to adjust the timing ?
and is it points or electronic ? Electronic ignition never 'changes
timing' - normally it never needs to be adjusted.
On non-California air-cooled vanagons with points.............the timing
doesn't change, but the points do. usually you just replace those, or clean
and adjust them properly, check the distributor isn't too worn, and your
timing will be where it belongs again.
And you need to pay attention to whether the centrifugal advance is working
........not stuck, and not so worn it drifts around, and you need to pay
attention to the vacuum advance and/or retard diaphragms, that those are
hooked up and working if you have that )
but.......if things are where they need to be
generally.............basically all working, and all you need is the timing
decent.
On a warmed up idling engine ............do this :
Loosen the distributor clamp some,.........then while it's idling, turn the
distributor counterclockwise ( advance ) a bit at a time , which will raise
the idle speed.....
turn it until the idle speed stops going higher..........that's WAY
advanced.........like over 40 degrees, then turn it
clockwise............until the idle drops back down.........turn it in the
retarded direction until it's down to 400 rpm, almost stalling, that's WAY
retarded. Do that back and forth a few times........
then put the distributor smack in the middle of those two extremes.
If it pings when you drive it, it's too advanced. Move the dist. in small
increments clockwise until it doesn't ping. This will give you perfect
timing for good driving.
If it's for a smog check, that's a different story.
If the distributor is shot..........all bets are off.
I have retrofitted the electronic ignition from an 83 to 85 vanagon 1.9
waterrboxer Vanagon engine to an air-cooled vanagon just fine, and that is
VERY worth doing.
Points are a joke. They depend to much on the mechanical condition of the
distributor, and if stock and original........can't imagine that it really
works better than about 75 % as well as it did new.
any place there is an interface between something electrical, and something
mechanical, it's a fundamentally weak area -a points distributor is a prime
example.
Scott
www.turbovans.com
----- Original Message -----
From: "B.J.R." <beer_eighty@YAHOO.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Wednesday, October 22, 2008 8:43 AM
Subject: Re: Timing vanagon without timing scale, only insturment ?'s
> Hey David,
> Just a side note.
> Going through your equation below, I did my measurements on the crank
> pulley,
> 62cm = 620 mm/72 = 6.21111x5=43.055/10=4.30cm
> so taking that and marking that distance on the pulley I get A measurement
> But while doing this I found the chewed up timing scale stuck into pulley
> itself
> And found that the above equation result was way bigger then the actual
> timing marks spacing
> This morning it occured to me,
> 2 rotations equals one stroke so does that above equation need to be
> divided by 2?
>
> So I was able to time it temporarily mounting the demolished timing scale
>
> But I thought Id point out the discrepancy for others future use
>
> B
>
> 1) mechanically determine firing-stroke TDC on #1 cylinder, using a
>
> probe into the plug-hole. For check, the mark on the crank pulley
> should be in about the right place per the picture in Bentley.
>
> 2) Mark that position in the place where the scale should be.
>
> 2a) :-) Measure or otherwise discover the circumference of the crank
> pulley, then calculate the distance (circumference / 72) represented
> by five degrees. Assuming the engine turns to the right, mark the
> crank pulley that distance to the left of the TDC mark. Now time
> using basic timing light, but matching the 5-degree mark to the case mark.
>
>
>
> --
> David Beierl - Providence RI USA -- http://pws.prserv.net/synergy/Vanagon/
> '84 Westy "Dutiful Passage," '85 GL "Poor Relation"
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