Date: Mon, 14 Apr 2008 23:31:31 -0700
Reply-To: neil N <musomuso@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: neil N <musomuso@GMAIL.COM>
Subject: Re: Vanagon/Jetta timing issue. Use RPM sensor hole to find #1
TDC mark?
In-Reply-To: <71d9cdf90804142310y6f005fa3h84b00a1e0296946d@mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1
Hey Jake.
Yah that was one of the first things I did when checking for TDC.
Feeling for air coming out of spark plug hole. I also used a wood
dowel to fine tune. There is also a mark on the crank pulley that
lines up with a stationary mark on the timing belt cover. This
indicates TDC.
Here's what I did to the engine prior to install:
replaced timing belt, serp belt, water pump, switched to a non - AC/PS
setup in the process, (used a VR6 coolant pump pulley), rotor, cap,
plugs, some gaskets/o-rings etc.
I removed the distributor to inspect it.
As for the timing belt, I did make marks on the cam, but wasn't
certain about my markings (or possibly lack thereof) and had doubts
about timing, so did it by the book. I installed the distributor once
cam/crank were timed together, by lining up the rotor with the #1
mark, and installed it. When I rotate it by hand everything stays
lined up.
I never saw the engine run.
One thing I may still be confused about, is the intermediate shaft and
its' role in things. It drives the distributor, but AFAIK, if
distributor not installed, it doesn't need to be in any special
position in relation to the cam, crank and distributor.
There are likely some other bugs keeping this thing from running, but
given the way it sounds when turning it over, it sure sounds like it's
timed incorrectly.
I have heard that sound before! :)
Thanks,
Neil.
On Mon, Apr 14, 2008 at 11:10 PM, Jake de Villiers
<crescentbeachguitar@gmail.com> wrote:
> Just because the piston's at the top of its stroke doesn't mean its TDC.
> :)
>
> Pull the #1 plug and turn the motor over by hand with your thumb over the
> spark plug hole and you'll find TDC on the compression stroke. Fine tune
> with your stick if you prefer.
>
> Did you remove the distributor from the engine for some reason? If the
> motor was running fine before you swapped it over, the timing's close enough
> to get you started. Just clip your timing light on the #1 lead, point the
> light at the mark and crank away.
>
> Pour some gas down its little throat and crank again.
> Is there something you're not telling us?
>
>
> On Mon, Apr 14, 2008 at 10:00 PM, neil N <musomuso@gmail.com> wrote:
>
> > Thanks for the reply Mark.
> >
> > So ok......
> >
> > If I'm understanding this correctly, as long as #1 is at the top of
> > its' stroke, whether or not it is an beginning its' exhaust or
> > compression stroke, is determined by how I set the cam?
> >
> > FWIW, I'm treating this engine as if the cam, intermediate shaft,
> > crank and distributor are out of sync with each other.
> >
> > Currently it's timed so when #1 is at TDC, the cam is at its' correct
> > mark, and the distributor is at #1 mark. I confirmed TDC using wood
> > dowel in spark plug hole. Crank pulley mark lines up with mark on
> > plastic timing belt cover.
> >
> > But.......
> >
> > In Bentley it says that if the RPM sensor is faulty, the engine won't
> > start. I'm not assuming it's faulty, but my concern is that if
> > (ignoring cam now) I have #1 set to the "exhaust" stroke in relation
> > to the gap on the crank gear, that this may be fouling up the RPM
> > sensor, therefore keeping the engine from starting.
> >
> > Neil.
> >
> >
> >
> >
> >
> >
> > On Mon, Apr 14, 2008 at 8:59 PM, Mark Drillock <drillock@earthlink.net>
> wrote:
> > > You have a 4 stroke engine, also called a 4 cycle. (I don't mean 4 cyl
> > > though yours is that too)
> > >
> > > With a 4 stroke engine it takes 2 complete revolutions of the crank to
> > > complete a full cycle. With a 4 cylinder 4 cycle that means the crank
> timing
> > > mark will line up for 2 different cylinders at TDC at the same time. One
> > > will be lined up in its compression stroke TDC and the other will at the
> > > same time be lined up for its exhaust stroke TDC.
> > >
> > > The firing order of the VW inline engine is 1-3-4-2. That means that
> cyls 1
> > > AND 4 will be at TDC at the SAME time, but at different phases of their
> > > valve timing. VW provides a cam timing indicator so the valve timing
> phase
> > > can be checked against cylinder #1 TDC. Once timing for #1 is correct
> the
> > > others must also be so.
> > >
> > > Mark
> > >
> > >
> > >
> > >
> > > neil N wrote:
> > >
> > > > Hey everyone.
> > > >
> > > > Haven't got my Jetta ABA 2.0 engine started yet. Timing sounds wrong
> > > > even though I have timing marks "correct".
> > > >
> > > > When engine turned over, it sounds like this:
> > > >
> > > > "whir whir whir" (slight pause) "whir whir whir" etc. It sounds
> > > > labored with very distinct "whirs" if that makes sense.
> > > >
> > > > Starter is fine, as is battery.
> > > >
> > > > I need to confirm TDC of #1 cylinder, but obviously can't see the
> > > flywheel.
> > > >
> > > > Bentley shows a gear attached to crank, that RPM sensor "reads". There
> > > > is a factory gap on gear. (2 teeth missing). RPM sensor reads this gap
> > > > as TDC for #1 cylinder.
> > > >
> > > > With sensor removed, and gap on gear lined up with RPM sensor hole in
> > > > block, crank pulley mark is at 9:00 and distributor points close to
> > > > #4. This somewhat confirms my suspicions. But i"m not certain.
> > > >
> > > > Anyone know if I can use this gap on the gear as reference for #1 TDC?
> > > >
> > > > This is an interference engine AFAIK, so I don't want to screw with
> > > > timing any more than I have! --- :^)
> > > >
> > > > Thanks,
> > > >
> > > > Neil.
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