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Nigelf
15-10-2008, 04:29 PM
I'm running a 1300 "AB" engine in Omie with a 009 dizzy: there's a huge flat spot and she bogs down badly when pulling away. I have to pump the accelerator a couple of times at junctions to pull away and even then it's a crawl for a few seconds. Once up to speed there's no problem (although sometimes she cuts out as I'm coming to a halt). Is this the dreaded 009 flat spot that I've read about or should I start looking elsewhere?

I pulled the plugs and they're a lovely tan colour and I've adjusted the automatic choke. Anyone got any ideas where I should look next?

Big Birds Car
15-10-2008, 05:03 PM
I have no knowledge of aircool'ds but in general I would look at timing first and possibly the carb, however you say that the accelerator pump is working on the carb so it points me more to the timing/distributor. (just check that the accelerator pump is pumping fuel in when the throttle is pressed, do this with the air filter off and the engine switched off then just operate the carb linkage and see if petrol is pumped in).
Other than that I can't suggest anything else.

Nigelf
15-10-2008, 06:48 PM
Thanks BBC.

This is more for the aircooled types:The dizzy has this number on it 0231178009. I checked on the oldvolkshome site and there it's shown as a being for "VW High Performance Applications". Does that mean it's not the right one for my engine?

NovaNigel
15-10-2008, 08:53 PM
Nigelf

I have been running 009 distributors on VW engines for many years and have never experienced a flat spot as you have described.

I would initially check the carb for blockages and ensure that any vacuum advance fittings on the carb are blanked off if you have them.

The only other issue I once had with a centrifugal distributor was a spring had come of/broken in the dizzy which controlled the advance weights which could give a similar effect.

Hope this helps

Nigel

Nigelf
15-10-2008, 10:15 PM
Thanks, NN.
I'll check those out: it could explain the cutting out as I come to a halt.

letterman7
16-10-2008, 02:02 AM
Sounds like a plugged idle circuit, too. Check everything and change those fuel filters - you have them, right?

Nigelf
16-10-2008, 08:25 AM
Well, at least one fuel filter, dangling by the carb. Are there any more?

Just one more thing to add: the tickover is fine when stationary, it's only when slowing down and coming to a halt that the engine dies.

Got to go away for a couple of days, so it'll have to wait until after the weekend.

Spacenut
16-10-2008, 09:11 AM
Hi Nigel - its good to hear that you are finally on the road in your own Nova, even if it is bogging on the line :D

Your symptoms don't really sound like the ignition side to me - pulling away from a standstill the throttles will be open (possibly wide open) and the manifold depression will be small, so the vacuum advance will be negligible - also, the engine speed won't have got to the point where the mechanical advance is significant. Check for vacuum leaks in the advance canister, the vacuum pipes and around the base of the carb - also any vacuum take-offs for servos etc. (unlikely in the case of VW, but I got a similar problem on TGM after a vacuum plug fell out of my inlet manifold).

If you are satisfied that there are no leaks altering the air component of the fuel/air mix, then the next thing to consider is the carb itself - it may be jetted for a larger engine (often in the mistaken belief that bigger everything = more power), which might explain the problem - however, if a couple of pumps on the accelerator are what keeps it going at junctions, it sounds like you have a lean mixture, rather than an overly rich one.

BBC is also right on the money - the various emulsion tubes and idle jets can be blocked by very small pieces of sediment, which can easily get through your fuel filter (replace if in doubt, also check delivery from the fuel pump - the blockage may be further along the line); again, I speak from bitter experience :(

Good luck Nigel, get that Nova back on the road, frightening the locals - its what it was designed to do :D

Lauren

Nigelf
19-10-2008, 07:00 PM
Spacenut shoots and scores :clapping: :clapping: :clapping: :clapping: Many thanks.

I easily got a half turn on the nuts at the carb/manifold joint. Still had the flat spot and now no idle at all when warm.

It's a 30PICT3 carb with a big screw near the drain plug. I had to back it out about two miles before I could get a tick over. Went for a spin and the flat spot has practically disappeared, :D but she feels a bit down on power. :annoyed: I found a procedure for setting the carb on the Samba ( http://www.thesamba.com/vw/forum/viewtopic.php?p=3339726 ) so I'll give that a go tomorrow.

Spacenut
20-10-2008, 08:23 AM
Well done Nigel - sounds like you've found the cause of the flat spot. If you're still down on power, check the ignition timing once you've set the carb up - it may have been over-advanced/retarded in order to get the engine running at all on such a lean mixture. Then again, the 1300 was only good for... what? 40 bhp at the flywheel? Take off 30% transmission loss that leaves 28 bhp at the wheels, so it was never going to set the world on fire...

Lauren

Nigelf
20-10-2008, 11:40 AM
I know it's only little but it keeps me satisfied. It's an AB series engine which was supposedly good for a bag ripping 44 bhp. So far, no one knows what a Nova is here, so they are treating her with respect. It was a bit embarrassing with the flat spot because people would see me coming and rather than pull out in front of me (like they normally would) they would wait to let me pass. Sometimes the wait was a bit longer than they expected as she struggled to get out of the flat spot. :oops2:

Ordered a couple of Gunson goodies last week: a Colo(u)rtune and a timing light with advance feature. When they arrive, I can really get stuck in.

I've got the contrôle technique tomorrow which is necessary for applying for French registration. Unfortunately, I've only got one LHD headlight, which I haven't fitted yet. I went to an Autojumble yesterday and much to my delight found a Hella Ford Capri light. Just the one unfortunately and when I came to fit it, discovered that the shape differs from the UK Lucas ones. It's slightly taller and more rounded at the ends so it won't fit the UK shape frames. Given that my main priority is getting the engine running well, I don't have time to deal with that today, so I'm going to try strategically placing tape on the lens to block the left side dip and see whether I can get through like that.

Spacenut
21-10-2008, 09:47 AM
Good luck Nigel!

Interesting how the RH dip lights have a completely different mounting frame - I guess it says a lot about the way the cars were built back then - the Mk1 Capri was Dagenham's baby (the rival Cologne proposal lost the design competition), so no thought was given to LHD markets at the design stage, and local parts had to be adapted to fit :(

How does the Hella rectangular lamp unit compare with the Cibie lights I wonder?

Lauren

Nigelf
21-10-2008, 03:24 PM
The Cibiés are more angular that the Lucas. They also have four mounting lugs on the back.

I've found a breaker in the Netherlands who can supply me with a second headlamp and the mounting frames.

I failed the Contrôle technique on (no surprises) the headlamps and I think (because it's in French) a worn tie rod end. Other than that an advisory on the tracking, reversing light and an oil leak. I actually fixed the oil leak when I was doing the carb: it was a loose pedestal bolt. The tester just saw some of the oil that was hanging around.

BTW I tuned the engine by ear yesterday as my Gunson's tools haven't arrived. I tried to keep it slightly rich, as lean is a big no no for Beetles. According to the gas analysis the exhaust is CO: 00.08, CO2:04.10 COC:00.29 (no units given) anyone know what they mean? Can you tell if she's running rich or lean from those figures?

Spacenut
23-10-2008, 01:42 PM
Hi Nigel - the CO2 figures are usually quoted in %, 4.1 sounds pretty good to me (6% CO2 limit was introduced into UK MoT for post 1976 vehicles, and I think the current limit is less, but I can't remember what). Bottom line is you would probably pass a UK emissions test even if registered after 1976...

Ben is probably your man for the other readings - although I suspect the CO levels are in ppm.

As to whether the engine is tuned OK, I'd say you're in the right ball park...

Sounds like you're not far off unleashing your 44 bhp on the unsuspecting French for real!

Lauren