Club 80-90 Forums

jamesandtheopenroad wrote:Hi 8ball

So cleaned up the dizzy and replaced the vac advance (as well as cleaning up the earth connections on the engine and resetting the timing) and it's running much better.

I got my vac advance from http://www.simonbbc.com/ignition-spares ... vance-unit.

Thanks for the info James, glad to hear you've made progress!

Is there a real idiot's guide to checking/setting the timing anywhere? A video would be great. I've found a couple of youtube which are Aircooled specific but I presume the principle is the same? Am I right in thinking that on the DG, at idle, with the vac disconnected, the timing light should show a 'V' on the pulley in line with the split in the crankcase?

One more Q whilst it's on my mind - would anyone like to weigh in with opinions on spark plug choice? The van is currently running Bosch WR78's...

haynes and wiki for those questions

haynes has a step by step.
wiki has the plugs

8ball wrote:

jamesandtheopenroad wrote:Hi 8ball

So cleaned up the dizzy and replaced the vac advance (as well as cleaning up the earth connections on the engine and resetting the timing) and it's running much better.

I got my vac advance from http://www.simonbbc.com/ignition-spares ... vance-unit.

Thanks for the info James, glad to hear you've made progress!

Is there a real idiot's guide to checking/setting the timing anywhere? A video would be great. I've found a couple of youtube which are Aircooled specific but I presume the principle is the same? Am I right in thinking that on the DG, at idle, with the vac disconnected, the timing light should show a 'V' on the pulley in line with the split in the crankcase?

Hello,

Please... not from the split line of the crankcase..

This may help, (latter part..)

http://www.youtube.com/watch?v=fOiSOObjk2E

As you say, its the same for wasserboxers, because they are all effectively built up on the geometry of the CT block..

Cordialement,

Hi all, just to bring you up to date, spent the afternoon working on the van yesterday and made some good progress. Started with a compression test and got the following results:

cylinder 1 - 161psi
cylinder 2 - 160psi
cylinder 3 - 170psi
cylinder 4 - 160psi

So, all looking good there as far as I can tell, though any reason no.3 would read higher than the others? Seen a few results from other owners on here and seems more common if there's an imbalance to have one cylinder lower than the rest.

Following that, swapped out the Bosch WR78 plugs for the originals the van came with (WR7DC+) which needed to be cleaned up as they were very sooty, then put everything back together and hooked up the new timing light. Vac advance disconnected, no idle stability unit to bridge, the light showed that the timing appeared to be approx 5º retarded. Bit worrying, considering the last person to set the timing was supposed to know what they were doing. So from there, rotated the dizzy clockwise until the V notch was lined up with the crankcase split, at about 950rpm and saw immediate improvement. Increasing the revs resulted in the timing marks appearing to move anticlockwise on the pulley, confirming that the centrifugal advance appears to be doing its job. From there, rotated a further 5º clockwise and idle smoother still. Went out for a spin and power was definitely increased across the rev range and especially in fourth and fifth, with an indicated 82mph flat out on the ring road (on a slight downhill, admittedly). On the flat a bit over 70mph is doable, provided you get the revs high enough in 3rd. Does that sound reasonable to anyone else with a DG or is there any more to try to tease out of it??

There's still the occasional mild stutter when pulling away at low revs, and the economy isn't great, so think the carb would benefit from being set up properly by someone with a gas analyser, but overall feeling pretty pleased that the van is now useable. Went down to the coast today and had our first cup of tea, made on the stove, so the last few weekends of head scratching have all been worth it! Thanks to everyone for the helpful comments so far, I've learnt a lot in the last few weeks, and will feel a lot more confident as and when things need attention in the future

Cheers

Chris

VW put the v notch there to help you set the timing correctly
By moving it a further 5 deg off the mark, it is now incorrect for a DG.

The gas anyliser will only tell you the mixture at idle
The main jets sre set in stone and should not have to be changed

Kev, thanks for your advice once again, maybe you could help me clear up once and for all where I need to be with the timing!

Haynes says to set the timing so that at idle, with the vac advance disconnected, the V notch on the rear of the pulley is in line with the crankcase split. The round mark on the front of my pulley I measured at roughly 5º anticlockwise from that, so is this then correctly set for 5º BTDC? In an earlier post, sarran1955 suggested that this was a definite no-no. Additionally, once the vac advance is reconnected the marks shift a few degrees of advance, so does this need to be compensated for by rotating the dizzy so the V notch is back in line with the crankcase?? Compounding it all, the engine seems to be running best at the setting I've got at the moment, which sounds like I'm now more at something like 10º BTDC, yet I don't seem to be getting any signs of pinking. The more I've been trying to get my head about this, the more confused I'm getting!

The "u" shaped notch is TDC
The "V" notch, smack on the case line is the correct firing point for the DG 1.9 engine. (vac disconnected)

What is confusing?

and why do you confuse yourself with wondering about vac advance compression

No, don't re-adjust after re-connecting vac. Also, don't presume you are looking for a high idle when swinging dizzie. The static position is just that which gives the best compromise adv. curve throughout the range when all connected back up.

Does sound like you' re close though. Be careful, keep ears peeled esp. in hot weather and don't change things too often. Get used to it first, try not to stab in the dark. Keep detailed notes with changes, dates and mileometet readings. Log your fuel and milo readings properly, few do, always tells a story!

Pressures look good, No. 3 is not that high c.f. others, quite normal to have a high one (seen over 220 in a Fiat I rebuilt)