starting issues, what could it be?

[martijn447]

Hi there,

I recently done some improvements on my 1500s notch from 1963.
- new points
- new spark plugs
- new ht leads
- new coil
- carbs are rebuild and tested on another engine (they work fine)

I set the timing at 10 degrees BTDC static. And fine tuned it with a timing light. Still the engine has trouble starting, both cold and hot. A local VW specialist told me that due to bad fuel quality it is better to set the timing at 10 degrees more advanced, so 20 degrees BTDC. Don't know if this is a good idea.

Any ideas? Could it be something else? Like the condensor or vacuum advance canister.

[glutamodo]

If you are simply compensating temporarily for bad gas, I guess advancing the timing like that might work. However that is not something I would do other than very briefly.

Have you checked to see how strong of a spark your coil is actually delivering? What dwell are the points reading? Have you checked to see how well your distributor advance is working, and what kind of distributor is it, anyway?

-Andy

[Slow 1200]

have you measured compression lately?
advancing timing 10º further seems like a really bad idea to me

[krusher]

[martijn447]

Dwell is 70, could that be it? I will try a bigger point gap then. Compression is tested, it's not that bad. I noticed there is no difference when I pull the vacuum hose off with engine at idle speed. Is this normal? I tested the vacuum advance system by sucking, and it works fine.

[Mike Fisher]

Jim Adney says 50 for dwell!
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[glutamodo]

Bentley says 47° +/- 3° for dwell - you need to set yours in that range and then reset your timing.

[sharkskinman]

yes 70* means your points are Not opening at all

the car will still run but like Ass!

mine holds steady at 47* on my F.I.
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[martijn447]

Here's a little update on my results so far. I changed the points for new ones and on close inspection the old ones were pitted (after 500 kms) so I also changed the condensor. The starting is fine now. Still the dwell keeps reading 70 ???? Gap is set at 0,45 mm, so that should be ok. Maybe my dwell meter is no working properly, but how can i test this?

Another problem is that the engine runs fine most of the time but then all of a sudden without doing something it's running very bad, doesn't hold idle and barks out bad smelling fumes. I think it's something in the ignition system, but I changed everything except for the distributor cap and rotor, but they seem fine.

Any ideas? Can I test the rotor and cap? for the record: my engine is totally stock with 6 volt electrics, twin solex 32 PDSIT, distributor is a bosch ZV/PAU 4R6.

[KTPhil]

Is your dwell meter set for 6 or 8 cylinders?

[martijn447]

Now I'm really stuck. Today I set the point gap to 0,5 mm. I checked that it is the same on all 4 cam lobes, and it is. Still the dwell stays at 70. Then I tried my dwell meter on my Moto Guzzi and it reads 40, so the meter is working fine. I have new points and a new condensor installed. I bounced my head a few times against the wall, but still the dwell is 70. Help! Should I open the gap even further?

I have a normal timing light/dwell meter combi (see photo).

[img][/img]

[Mike Fisher]

Point Gap = 0.40 to 0.50mm (.016 to .020 inches)
_________________
http://s169.photobucket.com/albums/u236/mr_bojangles500/
69 FI/AT square Daily Driver
66 sunroof,67,71,71,71 AT,72,72 AT Parts
56 & 57 oval ragtop $2,500

[martijn447]

Ok, so here's a little update on my 63' 1500s Notchback.

I discovered that my dwell meter was reading strange numbers because it doesn't work on 6 volt. So I set the gap as accurate as possible at 0,4 mm and don't bother about the dwell.

The engine runs, but there's a thing I can't get my head around:
When I start the engine (cold or hot) it sometimes runs on 3 cylinders, if it does that it doesn't hold idle so i'm just revving it to keep the engine turning. Then after a while it runs normal (probably because a fourth cylinder fires up). When I then shut it off and restart it, it sometimes runs fine and sometimes back on 3 cylinders. Here's a list with things I checked/renewed:

- new points
- new spark plugs
- new ht leads
- new coil
- new distributor cap and rotor
- new condensor
- rebuild the fuel pump and set the pressure
- carbs are rebuild and tested on another engine (they work fine)
- compression (138 psi on #1, #2 and #4 and 132 psi on #3)
- checked for vacuum leaks (didn't find any)
- cleaned all electric connections, also on battery and ground strap

I really don't know what to check or renew else. This way it's not reliable and I hope to fix it so I can enjoy the spring sunshine here in the Netherlands (20C/68F on march 24th )

Good ideas anyone?

[Tram]

[martijn447]

[EverettB]

My dwell meter doesn't work that well on my 6-volt battery-equipped cars either but I hook the power for it straight to the unregulated generator and then it works.
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[martijn447]

The dwell is not my biggest problem at the moment. It's the running problem right after starting the engine I can't figure out.

The funny thing is right after starting it seems the engine runs on only 3 cylinders (lots of unburned fuel, heavy smell, no idle), but after a while of revving it (1 minute), the engine runs fine on all 4 legs.

Could it be the distributor itself? I checked it and there's only very little side play on the shaft. All the other parts on the dizzy are new.

[Tram]

[Bobnotch]

[Tram]