Coldstart problem

[dafix]

Hello folks,

I have the following problem with "Kaatje" my 46: today, outdoor temperature was about 5 C. The air-filter lever was in "winter" position (the hot-air duct of the air-filter pan is actually a bit leaky and I have to replace it). I put the choke at half-way and managed to start up, but the engine could not stand the idle after a minute and got killed after a few seconds. I tried different positions of the choke, and at best the engine kept running but didn't rev up when I depressed the throttle pedal and had very few power: my DAF moved very slowly and was unable to climb the gentle slope of my driveway. When I released the pedal, the engine got killed again. Last winter, with the same temperature I didn't get this problem (although cold starts were always a little tricky and it took some time to warm up while parked). I haven't drive my DAF on open roads since the beginning of November (due to the lockdown in France), just started it every week, pulled it outside the garage, left the engine running for a few minutes, and bringing it back into the garage. Could it be more likely a carburetor or an ignition issue ? In the former case, I am not sure what to check first. Any suggestion is welcome. Thank you and happy 2021 (hoping it will be better than 2020 for everybody).

[andrew]

Hi there!

It sounds like it might be a condenser failure, which in turn causes a poor spark at the plugs, thus leading to poor running, lack of power and inability to move! That would be my first thought, since condensers fail catastrophically (meaning they fail "just like that"-sorry, Tommy Cooper!) as opposed to gradually giving up. If you are able to examine the points there's a test you can to to confirm if the condenser's failed:

1/ Remove the distributor cap and remove the rotor arm & dust cap. This will expose the points.
2/Using the fan belt, turn the engine until the points are fully closed. Now switch on the ignition, but DON'T start the engine.
3/With a PLASTIC stick, separate the points and watch for the spark. If you see a big fat spark or flash, together with an audible thwack, the condenser's failed, as it's this jolt that the condenser is supposed to smooth out. If there's no flash, or a very small one, the fault lies somewhere else.

Assuming that the car's had no other changes that you've noticed, such as a change in fuel supplier, which might have old or stale fuel (unlikely!) Take a look at the H.T. leads and check they're properly connected, as they may have worked lose, and don't forget to check the coil lead, too.

Good luck and report back with the results!

[dafix]

Hi Andrew,

Thank you for the advice. However my DAF has been equipped with an electronic ignition by the previous owner and I am not sure there is still a condenser (capacitor ?) installed, I have to check. If the electronic had failed, then I guess the engine would not start at all (likely because the transistor has burned). I can also check the spark plugs and their connections. Also, there is a wire between the coil and something (solenoid valve ?) on the carburetor. I don't know the purpose of this rig, but in case of failure perhaps it may explain the current behaviour of the engine. Even in summer, I noticed that, when the engine is warm (after a drive) and idling (gear in forward or reverse and parking brake engaged), it eventually stops after about 20 seconds.

[andrew]

Gotcha!

That solenoid is a vital part of the carburetion process and it's easy to test! Switch on the ignition, but DON'T start the engine. Now remove the wire that's attached to the solenoid and you should hear a "click". now re-connect it and you ought to hear another "click". This noise indicates that the solenoid is working properly. If you don't hear that click, the solenoid is NOT working and you need to find out why. First, see that you have a 12 volt feed at the wire when the ignition is on. If there isn't, investigate why-the ignition isn't fused on most Dafs, but I'm not 100% sure about a 46. If the 12 volts is there, remove the solenoid (it unscrews from the carburettor body) and then see is it clicks when earthed to another earth. It's possible the solenoid has failed (I have a spare if you want one) but I'll await your investigations before going on!

[Richard DAF Webmeister]

Dec 31, 2020 18:55:23 GMT andrew said:

Gotcha!

That solenoid is a vital part of the carburetion process and it's easy to test! Switch on the ignition, but DON'T start the engine. Now remove the wire that's attached to the solenoid and you should hear a "click". now re-connect it and you ought to hear another "click". This noise indicates that the solenoid is working properly. If you don't hear that click, the solenoid is NOT working and you need to find out why. First, see that you have a 12 volt feed at the wire when the ignition is on. If there isn't, investigate why-the ignition isn't fused on most Dafs, but I'm not 100% sure about a 46. If the 12 volts is there, remove the solenoid (it unscrews from the carburettor body) and then see is it clicks when earthed to another earth. It's possible the solenoid has failed (I have a spare if you want one) but I'll await your investigations before going on!

Yes. Andrew is correct about the solenoid. Ensure that it is firmly screwed in to the carb, and that the wire connected to it has a good connection.

Many times over the years with my DAFs, the solenoid has vibrated loose, and caused the same rough running and stalling after a few seconds. (The solenoid is all to do with exhaust emissions)

Good luck!

[dafix]

Hi, I have tested this solenoid as suggested by Andrew and it works fine (this is actually the "click" I always hear when I am behind the wheel and turn the ignition on before starting). It seems to be correctly attached to the carburetor (I will check it again). Also, I have noticed there is actually a capacitor beside the ignition distributor (I thought it had to be removed when an electronic ignition is installed). There is also another capacitor beside the coil, so I have to figure out in details how this ignition system works.

[andrew]

If it helps I can explain how to test the capacitor (or condenser, it's a different word for the same thing!) if you have a decent multi-meter to hand. If you're fairly adept you might not have to remove it from the car either! In electrical terms the capacitor "smooths out" the effect of the points opening and cushions the break in the circuit. By connecting a multi-meter across the capacitor and selecting the highest resistance option (usually 2M ohms) the reading should slowly rise from zero to infinite in a few seconds. If it goes immediately to infinite, it's probably dead, but let's see how you get on first.....

By the way, a Happy New Year (Bonne Année) to you! As of today, we have left the European Union (or, as we say over here, The E.U. has left us!) but the "Entente Cordial" between our nearest foreign neighbour and us is as strong as ever, I assure you!

[paull]

Hi Dafix,
Also, if the condenser/ capacitor resistance stays at zero then it is also toast.

My guess is that it shouldn’t have or need two attached, and that a second one was added because the original was failing,. Now I would suspect that one has failed completely and is shorting out the system.

You can get cheep but functional capacitor testers on a popular auction site such as this:
www.ebay.co.uk/p/21039754041?iid=202852291436
They work quite well, and after having a few condensers go wrong on other vehicles I found the tester useful to confirm the diagnosis

Paul

[starider]

Just a thought, have you put the winter weather sheild in behind the front grill?

Tony

[dafix]

Hello,

Happy new year to you all, and thank you for the replies I got on a 1st of January !

andrew : yes, I can use this trick but I think it would work better with an analog multimeter (I have an old one somewhere, probably need to replace its battery for the ohm-meter function). Regarding Brexit, I hope it will not cause too much hassle for you people when you will import DAF parts from the Netherlands (or other places in EU)... Passion has no border: I am french, posting on a british forum about dutch cars !

paull: your hypothesis is interesting, I will check if the two capacitors are in parallel. I have checked the manual of the ignition system installed by the previous owner: it is a special Ducellier "Ville-route" (city-road) ignition coil that comes with a small electronic box and a resistor (to step-down the +12 V for the electronics ?). There is no mention that the original ignition capacitor has to be removed, so what I see is perhaps normal (except for this second capacitor).

starider: I have no winter shield (it was not included when I bought my DAF), but I guess it is efficient only when driving on the road (to prevent engine cooling by the relative wind through the grille). If I fix my problem and can drive this winter, I will have to make up something (like at piece of cardboard behind the grille).

[starider]

Hi, they all came from new with a white pre-formed plastic sheild which clipped in behind the front panel grill. I'm not sure if it was discontinued later in production. Maybe Matt has one somewhere.

[bobdisk]

Hi, Vrolijk kerstfeest en een gelukkig nieuwjaar, Joyeux Noel et bonne année, Frohe Weihnachten und ein glückliches Neues Jahr, Merry Christmas and happy New year !!! International Greetings!!!
I have recently got a car (a Reliant Kitten) where the previous owner had fitted an electronic ignition, where it is a magnetic pickup from the distributors cam. There are no points, the unit fits where the points were. The connections are 12V in, signal out to the coil, and earth. The original capacitor is not required. I wonder if yours is a similar system. If you do not have points, the capacitor is not required.
If you do have points, with an electronic ignition, it is still unlikely a capacitor is required, this depends on the system. Look up the systems manufacturer, and check.

A standard system with points and capacitor, the capacitor is best measured with a digital multimeter that has a capacitance range. Disconnect first and then measure. The value should be about 0.22uF.

[dafix]

Hi, I tried to measure yesterday the capacitor with a digital multimeter in ohm-meter and it instantly returned an infinite resistance. However, I tried with a 0.44 uF capacitor (for mounting on PCBs) that I had in my drawers and the same thing happened, so I cannot conclude. I have to figure out another way to test this capacitor (I have already some ideas). Regarding the requirement of this capacitor, it is true that it is not required with an electronic ignition for which the points operate at low voltage to control the base of a power transistor (that acts as a switch for the coil). I bought some years ago such an electronic ignition: a Velleman kit that I wanted to install inside a Peugeot 404. I assembled this kit but eventually never installed it in my 404 (which was sold before). I still have it and I am thinking to try it in my DAF, to see how it behaves (with a new coil) compared to the current Ducellier ignition system I currently have (installed by the previous owner).

[starider]

I did ask several months ago if anyone manufactured an electronic ignition kit for a twin cylinder engine which could be fitted to a 33/44. If there is such an animal I'll be first in the queue.Contact/capacitors have been the bone of DAF owners for years.

[starider]

Hi,
Just found a company who can supply a kit to convert a 33/44 distributor to electronic ignition.I've ordered one and will fit and test when received. If it does the job I'll give details[not expensive].The module fits where the points fit and 2 wires go to the coil.

[bobdisk]

Jan 3, 2021 20:32:21 GMT dafix said:

Hi, I tried to measure yesterday the capacitor with a digital multimeter in ohm-meter and it instantly returned an infinite resistance. However, I tried with a 0.44 uF capacitor (for mounting on PCBs) that I had in my drawers and the same thing happened, so I cannot conclude. I have to figure out another way to test this capacitor (I have already some ideas). Regarding the requirement of this capacitor, it is true that it is not required with an electronic ignition for which the points operate at low voltage to control the base of a power transistor (that acts as a switch for the coil). I bought some years ago such an electronic ignition: a Velleman kit that I wanted to install inside a Peugeot 404. I assembled this kit but eventually never installed it in my 404 (which was sold before). I still have it and I am thinking to try it in my DAF, to see how it behaves (with a new coil) compared to the current Ducellier ignition system I currently have (installed by the previous owner).

You cannot get a reliable reading of a capacitor on the ohms range on a digital or analogue multimeter. I have today tried an 0.047uF capacitor on several DMMs, mine and at work, and each was different! A modern DMM would have a capacitance range, so you can see the value or if it has gone short. Some sophisticated DMMs will also give you an ESR (Effective Series Resistance) range. An analogue meter, like an old AVO meter that has a 15v battery (battery now obsolete) for the higher resistance ranges, might give a slight "kick" of the meters needle, and then return to zero if the capacitors value is big enough, usually an electrolytic of at least 470uF. ( I have not heard of 0.44, the nearest preferred value is 0.47uF or 0.33uF)

I will see if I can identify the electronic switch in the Kitten. There are no contacts, it relies on an inductive sense of the existing cam as it goes past the sensor.

I have found Velleman, they do a lot of kits for all sorts of projects;   Is this your kit?    www.velleman.co.uk/contents/en-uk/p199.html    I would think it should work on the Daf, they say it will work on 2,(4,6 & 8) cylinder engines. An important thing (?) not mentioned, is to set the dwell angle (points gap) first.

Starider, I would be interested in the system you have found!

[paull]

Jan 4, 2021 15:49:05 GMT starider said:

I did ask several months ago if anyone manufactured an electronic ignition kit for a twin cylinder engine which could be fitted to a 33/44. If there is such an animal I'll be first in the queue.Contact/capacitors have been the bone of DAF owners for years.

I wouldn’t be surprised if a kit for an older moto guzzi would work on the two cylinder DAF engine. You’d want one for the older round barrel engines up to the ‘80s as they still had distributors. 
the later bikes have points or sensors mounted on the end of the cam shaft, and I don’t think that would work on the DAF ( not that I know the air cooled engine at all)

not that I have used either but here are two

such as the Newtronic Piranha autocar-electrical.co.uk/newtronic-product-guide

or Electronic Sachs www.elektronik-sachse.de/shopsystem-3/en/digital-ignition-zdg-3-23-for-guzzi-distributor-mounting-points.html

[andrew]

The other comment I would offer is that the capacitor needs to be electrically isolated before it's tested. testing it in situ may well mean you have an inaccurate reading on your meter, as well as being somewhat tricky to make sure you're connecting the right parts to the meter! I have an original capacitor, approved for use in the Daf 33 ignition system and I'll video me testing it when I have a chance. This might help you in understanding how quickly the meter would move. The ideal reading for a capacitor fitted to a car's ignition system is 27 Nano farads.

[dafix]

Hi, I am a little busy now and haven't work on my DAF. Nevertheless I searched the web to understand the ignition system currently installed. It is a Ducellier 2794 electronic coil. This coil comes with a ballast resistor and a small electronic box that can shunt the ballast resistor, depending on the engine rate (as measured from the ignition points). The low-voltage signal from the points directly feeds the primary of the coil. Therefore this system cannot be called an "electronic ignition", as I naively thought, and the presence of a working capacitor is certainly mandatory.

My Velleman kit is the one for which bobdisk gave the link. I saw that dafhobby.nl sells an electronic ignition system for DAF, a little expensive (that probably features a Hall effect sensor and some electronics to adjust the timing).

[dafix]

Hi, finally I bought a capacimeter (I do some electronics sometimes, so this tool can be useful for me in the future). I measures 0.19 uF on the ignition capacitor, so it's OK. I started up my DAF today and the engine seemed to run smoother, but the temperature was 10 C, so not as cold as before. I replaced the warm air duct that goes to the air filter (still set to "winter" position). There is still a tendency to run below the idle rate when the engine is cold and I release the foot from the throttle pedal. Maybe I should tweak the throttle cable to have a higher idle rate (keeping it below the limit for the clutch, of course), I will see...

[starider]

I am waiting for my distributor to come back from the electronic ignition supplier. They offered to fit a kit for me. They will send a kit for me to fit on the Pick-up. Once I have checked it all out I'll post details.