Siba solenoid help needed

[steven mandell]

I have 2 1959 Nobel 200's.  One of them arrived with a non stock American replacement for the solenoid that is supposed to be in the Siba black box.
I suspect that it is causing problems with the engines ability to crank over, as this ability has progressively required greater amperage from its battery source to get the engine cranking. 
At this point even 2 batteries connected in paralell (by jumper cables so they are only supplying 12 volts) only produces a "fwop" type sound from the solennoid and is accompanied by very little if any cranking in one direction only.
I already bought the flywhell extractor for its Messershmitt motor and checkd the brushes and commutator.  They were all in good shape and clean.
It has a rocker switch on the dash instead of the original reversable ignition switch to change direction of engine rotation.
Can anybody suggest a cost effective parts replacement solution?
I have verified that the engine is not too stiff to be turned over easily.
Thanks,
Steven Mandell 

[Rusty Chrome (Malcolm Parker)]

This chap really seemed to know what was what in electrical matters on the Reliant forum. Perhaps he can provide a few pointers

http://www.aoservices.co.uk/

[Big Al]

Are we talking about the starter soliniod in the regulator or the changover switch from forward to reverse? If the first then isolate the output and check for currant either side. If the second we are into home wiring as whatever soliniod has replaced the original one will either be fitted to the switch so as to salvage the wiring needed or as a replacement having many variables that cannot be guessed. However you can test the dynostarter for forward and reverse via the dynostart leads so proving the dynostarter - see website or Karotips book or I can supply info. Likewise, again, the current into the changeover switch can be tested to prove the changeover switch is at fault. Contacts can be contaminated or burned, dirt can prevent correct movement to create good contact. A poor joint can create heat and a rising resistance.

[steven mandell]

Thanks Al.
 Sounds like eminently logical advise- but to be usable to an otherwise intelligent but electrically dumb individual such as myself i will need to know:
 1) to which alpha/numeric terminal, or detached electrical wire lead, or ground do I need to connect each of my electric meter meter test leads to.
 2) If it matters and if so- To  which key engaged position of the ignition switch  am I performing the test?
 3) Am I simply going to read Voltage, or do i need some specialized amp meter that i think I do not have.

The idea of jump wiring the change over rocker switch that replaces the reverse engaging both clockwise and anticlockwise turning original ignition switch sounds logical but a bit scary as Andy Carter once mentioned to me that if this rocker switch was accidentally engaged when the engine was turning that it could likely burn out something very expensive in the Dynastart system.

It does seem like a good idea to connect 12 volts from a good batterry directly to an isolated lead going to the dynastart to see if it will in fact turn over well if this is what would be expected when and if we could remove the suspect solenoid from the circuitry-   So which wire do I need to detach and supply +12 Volts to to accomplish this test.

I also like the idea of visually checking/ cleaning up contact points inside of a suspect solenoid if such an action is both do-able and advisable.  Got any pictures of the solenoids so that I can better orient my efforts?

Finally- what is the availability of replacement parts?  Are modern equivalents better of worse to use?
Are the ignition switch and box covers still available, and if so how much do they run?

Thanks for your help in pointing me in the right direction, as it is frustrating having an otherwise nicely road worthy car that can't be run at all.

[Big Al]

Blimey, that is an article of an answer in itself!

I am still not clear what the problem is. Its a reversing Sachs engine, correct? It used to start OK but has progressively got more difficult to start? Is that both forward and backwards? It should have failed backwards before failing forwards as it has less power starting on what are normally the 'generating' coils. If it starts one way but not the other then that points in a differing direction for the problem in the assembly. Has it got all the correct components or is it indeed modified? If it were me I would suspect the modification but electrics are best diagnosed in logical sequence nonetheless. Why do you need an ignition switch, that is dead easy to check? If the switch is not working correctly then it is a test from beginning to end on sorting it out if the problem persists. Remove the switch, if suspect, and create a very simple on/off system and that will test the circuits. Solving two problems at once is not easy, so one at a time by isolation is better.

If your lucky the black box lid will have a wiring diagram in it which will tell you which terminals do what. Failing that a support manual via Sachs or Messerschmitt or their club supporting literature with a diagram should be obtained as you are going to need it. Fortunately most of the electrics are repairable if things have not gone to far. Sadly the dynostarter can pull a current that can melt things and any fault is best checked out before it gets worse. Melting means scrap normally. Spares are drying up but I still run original bits and restore them for other people occasionally. I am doing a complete Black Box and a Berkeley regulator at the moment for two fellows. Cannot advise or recommend none original replacements but there are some which get tested in use till they do not visit the side of the road regularly and seem reliable. See solid state charging regulator system. They get mentioned on forums and sold on eBay etc.

The key test to see if it is a dynostart or wiring fault is to take the dynostarter wires off the car. First check that none of them go to earth. If you do not and put full power down the wiring something might terminally fail. If there is an earth service the dynostarter assembly till there is not. Dynostarters also need to be cleaned periodically anyway. Each brush can be isolated as can each set of coil trains. Carbon can build up and breach the insulation or the insulation fail. If no probs or the unit is restored proceed to do the following checks.

Forward - take cable B2/D+ and connect direct to cable HE/92L - small mole grip is good. Cable B1/92+ then goes to the negative terminal of a battery and A/30b to the positive. The engine should turn forwards, you can insert a meter to check readings.

Backwards - take B1/92+ and join it to HE/92L. This time B2/D+ goes negative and A/30b remains positive. The unit should spin backwards.

Clearly the labels of these wires Bosch or Siba will corresponding with the wiring diagram and show where the tests to the Black Box need to be done if the dynostarter is found to be good. The relays should shunt in a single brisk action and close clean contacts and provide current with a minor loss of energy across the component for starting. Do not short or close live solenoids manually or you risk a burnt out coil.
Both types of original changeover switches dismantle to access the points and mechanism. I am lucky enough to have new points sets and so on but most times you will have to clean everything up if its tatty. The regulators are more difficult to clean up and the contacts are pre set. The solenoids can be repaired but you need a steady hand with a soldering iron and some idea what you are doing.

Hope that helps

[Chris Thomas]

Dear Al

The testing and cleaning procedure for a dynastart sounds like a good subject for a Rumcar Article accompanied with some photographs and a wiring diagram.

Do you fancy putting pen to paper for all your friends?

Chris Thomas

[bubblenuts]

The original siba component has 3 bobbins inside, one being the starter one being the regulator and one being the cut out, if the non stock replacement part only has 2 bobbins inside then the starter soleniod will have be omitted and although the dynastarter might rotate it will not function as it should. I have a wiring diagram which might help if you let me your email address.

[Big Al]

Dear Al

The testing and cleaning procedure for a dynastart sounds like a good subject for a Rumcar Article accompanied with some photographs and a wiring diagram.

Do you fancy putting pen to paper for all your friends?

Chris Thomas

Such an article already exists and I think is on the internet which is why I suggested looking at club archives and publications to begin with. George Johnston did a very good one and he might allow its use in RUMcar.
I have my work cut out filing stuff for the MEC's Take Off at the moment. One thing I would love to do is create a restorers bubblecar manual but it is time and the lack thereof. Technical items involve a great deal of work so as to get them lucid but correct. Experience shows that many an owner, even with the correct info, is not equipped with the skills to do these tasks and it is becoming more apparent as wealthier buyers come in that there are those who recognise this and thus are asking those that can to do the job for them on a private but remunerated basis. Also as this paying activity builds up it leaves less time for providing for free things like fulfilling the above request sadly. Its all part of how the microcar world is changing fast leaving the less skilled or informed hobbyist behind.