Solanoid/dynastart

[Endeavourquay]

My engine wont turn over anymore, there is a 'click' noise from the solanoid, then nothing, having got the water out of the engine i want to keep it moving as often as I can, but having no luck starting it.
The solanoid was repaired on Sunday, and it started and ran for 10 minutes but by the next day I was back to just a 'click ' on turning the key.

Does anyone know where to get a 12v solanoid for a petrol engine, and does anyone have any ideas as to why the solanoids are failing or why else it might not be starting?
thank you /forums/images/graemlins/frown.gif

 

[PCUK]

Bad connections, damp, etc. Solenoids are available from any car spares shop. Have tyou tried thumping the solenoid with a hammer, they often stick when damp. If you had it "repaired" get it down again under warranty and properly this time!

 

[VicS]

You don't say what its for exactly but Fairways Marine Engineers in Maldon Essex 0621 852866/859424.
Hopefully the phone number is still correct, that's off a fairly old leaflet.

I assume you have a system in which the solenoid is separate from the control box. (some) earlier versions had the solenoid integrated into the control box (that was the Siba one IIRC). Later ones with the bits separate are I think Bosch. Fairways can supply the diagram if it is necessary to convert from Siba to Bosch.

If it's clicking its trying to work though. Check things thoroughly before parting with cash for a new one.

 

[VicS]

[ QUOTE ]
Solenoids are available from any car spares shop

[/ QUOTE ] Not like a car one, at least any I have seen. It's a little square box with 4 spade terminals I think you'll find (Unless its the old Siba type whre its integral with the control box)

A car one could be used I suppose.

 

[Endeavourquay]

Thank you, I tried lots of car shops but no luck so far, there is a motor factor that I need to take it to in order to match it up, Ive just had another go, hitting it with a hammer and yet another fresh spark plug and it worked, got it good and hot and have left the plug out so that the steam can escape, the engine is gradually drying out from last weeks discovery that it was full of water /forums/images/graemlins/frown.gif Fairways are probably the right guys to try, its a Vire, I never thought of them /forums/images/graemlins/blush.gif

 

[VicS]

[ QUOTE ]
its a Vire

[/ QUOTE ] I dont know about Vires I've only ever met one and that nearly sank the boat on its mooring!

I had to advise someone a while back on rewiring a Stuart Turner including converting from the old type Dynastarter control box to the new type with separate solenoid. He'd got the basic info and diagram from Fairways with the new bits but apart from that he had not found them very helpful.

EDIT
See the website for correct phone number http://www.fairwaysmarine.co.uk/

 

[pampas]

Place a voltmeter or lamp on the solenoid output to starter other end to earth, if you get a voltage with the solenoid engaded then the chances are the solenoid is ok, the fault will lie in the dynastrart, probally brushes. These items (The dynastart) are prone to dampness,better to remove it and take to an auto electriciad for final test/repair. It will not be cheap,but a lot less than a new one. Good luck.

 

[Flossdog]

I had a Vire for many years and although it wasn't very reliable, it was the ancillary bits that let me down. Anyway, I have a spare Bosch Dynastart you could have if you wanted it. PM me if interested.

 

[sandeel]

try contacting Nick as he is a specialist
Vire engineer

 

[Kyle2]

It may not be the solenoid that's faulty. I had a similar problem on my Volvo engine. I replaced the solenoid (from a car shop!) to no avail. Eventually I took the dynastart to a repair shop, and they diagnosed that the commutator was worn beyond economical repair - new dynastart required.

 

[Chrissie]

that might be an explanation, as its had two solanoids in nine months, I shall look into that, thank you,

 

[VicS]

[ QUOTE ]
that might be an explanation

[/ QUOTE ] The clue is in your original post. You can hear the solenoid clicking so it is operating I pointed that out in my first reply and that is why I suggested checking things out properly before buying another new one.

Clip a bulb, or a voltmeter, between the terminal that goes to the Dynastart (terminal 30 or A) and the negative and see if the bulb lights when the key turned to the start position. If it does and the Dynastart does not run then start looking at that.

But also check that you have a good negative connection between battery and Dynastart. (According to the limited info I have the Bosch machine has an earthing connection whereas the Siba does not)

 

[oldharry]

Vic is right, if the Solenoid is clicking, then it is almost certainly working properly. Its meant to click as it switches on and off! You need to go through things systematically to find out whether the problem is the Dynastart itself (bad news - £££'s) or a wiring fault. Negative connections are particularly susceptible to damp.

Like on the car when the battery is flat, all you get is a click when you try to start - which means there is enough power to operate the solenoid, but not enough to turn the starter.

 

[Endeavourquay]

Ah, things are getting clearer, I did a volt meter test and everything there was okay, but the negative conection might not be very good, at the moment the negative runs to a bar behind the electrics panel, I could try taking it direct to the battery negative.
The solanoid did start the engine after a whack with a hammer, so it is sticking, but there must be a reason for it sticking, multiple faults perhaps, the whole engine bay(and cabin) got a soaking when I was trying to clear the water out of the engine.

 

[roger]

The dynastart system is fairly nasty. When used as a current generator the control box relays "buzz" at high speed to keep the time averaged voltage between limits. The instantaneous voltage is either zero or large. Its only the battery that may save your electronics.
In any case the maximum possible current output is about 8 amps (working from memory).
In a similar situation I rewired the control system to use the dynastart only to start the engine and mounted an old car alternator to charge the batteries etc. via an auxiliary fan belt. This did not cost very much - in 2000.

 

[VicS]

[ QUOTE ]
The dynastart system is fairly nasty. When used as a current generator the control box relays "buzz" at high speed to keep the time averaged voltage between limits

[/ QUOTE ]

No body is claiming that it is the latest technology. An electromechanical regulator was the method by which car dynamos were regulated until the appearance of alternators in the 1960s. Even then some early alternators still used them. Well tried and tested I would say.

Likewise nobody is claiming that the output is high. They date from the days when people did not have any electrical equipment to speak of on board so just about all that was required was a low power motor capable of starting a tiny engine, that would have stated with ease with a handle or a bit of string, and a generator capable of putting back into the battery the small fraction of an Ah that the starter motor consumed.

 

[oldharry]

Dont see anything 'nasty' about it at all - a good way of starting a small engine and topping up the battery. Just somewhat dated, and sadly manufacturers have not thought to update the technology. I have one on my boat it and does everything it is supposed to do, and does it well, while saving the weight of a starter motor.

Anybody any ideas around making a solid state voltage /current control for when the old control box finally stops buzzing?

 

[VicS]

[ QUOTE ]
Anybody any ideas around making a solid state voltage /current control for when the old control box finally stops buzzing?

[/ QUOTE ] I wondered if the new ones are in fact solid state ones.