Date: Mon, 4 Jun 2012 19:49:56 -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: Possible Distributor Drive Shaft issue - Timing
In-Reply-To: <1872132506.1183280.1338834821343.JavaMail.root@sz0094a.emeryville.ca.mail.comcast.net>
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Hi..
sounds like a bit of a mess.
The first rule about the distributor drive gear in an air-cooled or
waterboxer engine is never, ever turn the engine ( particularily
clockwise I believe ) without the distributor installed and holding down
the dist drive gear ..
or at least something rigged to prevent the dist drive shaft from lifting.
I've seen new engines with a heavy wire bolted in place to hold that
drive gear down
the really slick way to assemble the cast is put the distributor and
dist drive shaft in the left case half, with the two shim-washers on the
bottom of the dist shaft and never take it out of there again during the
whole asembly process.
personally the way I make sure it's aligned right is I put the engine on
# 1 TDC to fire and make sure the dist rotor points to the notch on the
edge of the distributor.
if it does lift up, it is oh-so-easy for the two shim-washers to jam on
the brass distributor drive gear.
The suggestion to us grease to keep them where they belong is a good one.
the way to tell when it is really on # 1 TDC to fire is wathc # 3 valve
.....for 'point of balance' ..that's exhaust valve just finishing
closing and intake valve starting to open .
when you see that, # 1 is up on TDC to fire , and you should see the TDC
mark on the crank pulley line up with the case split, and the dist rotor
point to the notch in the top of the distributor.
You can of course, reindex the spark plug wires one position each ..
if dist is 90 degrees off.
that will work.
On air cooled engines ...# 3 is retarded a bit compared to the others. I
don't think that's true on waterboxers .
if you are using a 1.9 distributor ..there's not a lot of 'turn room' on
the distributor ..the vacuum capsule runs into things ..
as long as it is either right where it belongs, or a nice even 1/4 turn
off..
by reindexing the plug wires you should be able to get it working right.
the right thing to do would have been to assemble the engine from the
get-go with distributor and dist drive gear in place.
Those are the first parts I install in the left case half.
No books say to do that, that that I have ever seen though..
but it sure works perfectly !
scott
www.turbovans.com
On 6/4/2012 11:33 AM, Skip wrote:
> 1984 WBXR 1.9L (now 2.2 in a 1.9 case) just back from the machine shop. They installed the new innards and installed the distributor drive shaft...maybe incorrectly. Need help please.
>
> I finished the engine install yesterday and she started. I idled at about 2k rpms for about 20 minutes total (off and on). Then I took her for a ride (intending to break in the rings) and it was bucking in 1st and 2nd so I drove her back to my garage (home). I'm following Tencent's recommendation (samba search) for breaking in a renewed engine.
>
> Upon close examination of the dizzy drive shaft, the "smaller half circle" is 90 degrees away (smaller half circle points toward front of van) from pointing to the water pump (Bentley spec) at TDC. So, I figure that is the cause for bucking (timing way off). Perhaps my machinist did not place the distributor drive shaft in correctly? So I searched thesamba and found this thread.
>
> I took some samba advice and used a wood dowel (1/4") to lift the dizzy drive shaft 1/2 to 3/4" in order to turn the dizzy drive shaft 90 degrees leftward (counterclockwise). It wouldn't turn once I had it raised. I discovered, though, that I could turn the pulley without having the dizzy drive shaft turn when raised enough.
>
> So, I thought, why not move the pulley 90 degrees, push the dizzy drive shaft in, then turn the pulley back to TDC and Bob's your uncle. Not so. I couldn't get the dizzy drive shaft to drop back down into the drive shaft gears while the pulley was 90 degrees ATDC. Maybe I didn't wiggle it enough? Or maybe there's a reason it wouldn't drop?
>
> I'm back to square 1 with the dizzy in place, but off by 90 degrees. ...is this explained clearly enough?
>
> Help please?!
> _________________
> Skip
> 1984 Westy 1.9 WBXR Manual
> Since 26 July 2011
>
