Disco Timing

A few weeks ago I took my car into a service place known to a few here
for a timing chain - when it came back they said that the timing had
been a tooth off on the chain and that when they put it back on
suddenly the car wouldn't start - we'll need to sell you a new injector
pump mate!

Had it into a diesel specialist yesterday who, at 5:30 (took all day for
them to get a set of heater plugs!) checked the timing and discovered
it firing the injectors 10 degrees late, but the pump adjustment at the
stops. They reckon that they can move the timing chain back a tooth and
that they get around 18degrees to play with on the pump adjustment
after that, so should be able to get it bang on.

Makes me a bit suspicious about the "Need a new pump mate" place -
anybody else ever run across this one?

P.

"Paul S. Brown" <[email protected]> wrote in message
news:1619856.98kZpqL25j@PolMobile...
> A few weeks ago I took my car into a service place known to a few here
> for a timing chain - when it came back they said that the timing had
> been a tooth off on the chain and that when they put it back on
> suddenly the car wouldn't start - we'll need to sell you a new injector
> pump mate!
>
> Had it into a diesel specialist yesterday who, at 5:30 (took all day for
> them to get a set of heater plugs!) checked the timing and discovered
> it firing the injectors 10 degrees late, but the pump adjustment at the
> stops. They reckon that they can move the timing chain back a tooth and
> that they get around 18degrees to play with on the pump adjustment
> after that, so should be able to get it bang on.
>
> Makes me a bit suspicious about the "Need a new pump mate" place -
> anybody else ever run across this one?
>
> P.

Discovery Diesel - timing CHAIN? I thought all Disco's except the 3 had a
belt! Well known for it's own problems, but timing out, surely not. I seem
to recall that you lock the Disco flywheel at TDC, put a pin in the pump,
and Bob's your Uncle the timing is correct. I know this comes from the
Haynes manual, but surely it can't be that far off.


Cheers!
Graham Carter
Harare
Zimbabwe

whoever fitted the belt has probably not aligned properly or has moved
the camshaft gear , or they have moved the injector pump gear .

you need to ask how they changed belt , once they have told you, you
will know if they used locking pins on the gears or not .

i would suspect they have moved one of the gears whilst trying to get
the belt on , the belt does take some getting on because it is tight to
do so and without the locking pins in place it is easy enough to move
one of the gears round a tooth .

before taking old belt off you need to lock the flywheel in position at
TDC , then lock the injector pump gear using pins located thru holes in
gears and holes in the rear timing cover .
the crank gear has the keyway pointing directly vertically up and the
camshaft gear aligns via marks on the gear and timing cover .



the injector pump has a gear with 3 bolts through it, these bolts are
slackened off after the pump shaft has been locked in position which
leaves the shaft and injector pump itself locked so it cant move but
with the gear being able to be moved slightly left or right in order to
align the belt up with the other 2 gears but not to move the injector
pump timing/gear .

if it is only slightly out and the engine still runs then get them to
remove timing cover , lock injector pump in place using pin and hole ,
slacken off the pump gear bolts, then realign the camshaft gear marks
and flywheel TDC mark and lock pin .

they can take belt off after locking injector pump via lock pin so they
can then align the cam gear timing mark and flywheel/ crank at TDC .

once all aligned again reinstall belt and make sure marks are all in
line , then tighten pump gear bolts and remove all pins .
should be ok after that .

On or around Thu, 24 Nov 2005 19:33:57 +0200, "Graham Carter"
<[email protected]> enlightened us thusly:
>
>Discovery Diesel - timing CHAIN? I thought all Disco's except the 3 had a
>belt! Well known for it's own problems, but timing out, surely not. I seem
>to recall that you lock the Disco flywheel at TDC, put a pin in the pump,
>and Bob's your Uncle the timing is correct. I know this comes from the
>Haynes manual, but surely it can't be that far off.
>

typical of ingorami (the garage) in that they either don't know what they're
talking about or assume the punter doesn't

and yes, the "book" timing method is OK but it doesn't work if someone's
arsed around with it.

Having said that, I've tweaked ours a bit and it's running the pump a few
dergees advanced from the "correct" setting, which improves it. Ideally,
apparently, it's worth adjusting the cam timing, but the consequences of
getting that wrong are a bit off-putting.

"m0bcg" <[email protected]> wrote in message
news:[email protected]...
> whoever fitted the belt has probably not aligned properly or has moved
> the camshaft gear , or they have moved the injector pump gear .
>
> you need to ask how they changed belt , once they have told you, you
> will know if they used locking pins on the gears or not .
>
> i would suspect they have moved one of the gears whilst trying to get
> the belt on , the belt does take some getting on because it is tight to
> do so and without the locking pins in place it is easy enough to move
> one of the gears round a tooth .
>
> before taking old belt off you need to lock the flywheel in position at
> TDC , then lock the injector pump gear using pins located thru holes in
> gears and holes in the rear timing cover .
> the crank gear has the keyway pointing directly vertically up and the
> camshaft gear aligns via marks on the gear and timing cover .
>
>
>
> the injector pump has a gear with 3 bolts through it, these bolts are
> slackened off after the pump shaft has been locked in position which
> leaves the shaft and injector pump itself locked so it cant move but
> with the gear being able to be moved slightly left or right in order to
> align the belt up with the other 2 gears but not to move the injector
> pump timing/gear .
>
> if it is only slightly out and the engine still runs then get them to
> remove timing cover , lock injector pump in place using pin and hole ,
> slacken off the pump gear bolts, then realign the camshaft gear marks
> and flywheel TDC mark and lock pin .
>
> they can take belt off after locking injector pump via lock pin so they
> can then align the cam gear timing mark and flywheel/ crank at TDC .
>
> once all aligned again reinstall belt and make sure marks are all in
> line , then tighten pump gear bolts and remove all pins .
> should be ok after that .
>

Well explained - I had had a few when I wrote my bit. Good point about the
camshaft - I had forgotten you had to take that into account.

Could be that is what is out in Paul's case, but he sounds like he needs to
get a mechanic he can trust to check the timing using your correct
procedure.

All the best
Graham Carter
Harare
Zimbabwe