The Auck Posted December 4, 2015 Share Posted December 4, 2015 Have managed to get the v8 running nicely in my truck after a long lay off, but there is a weird thing happening when I start her that I can't work out so am hoping someone can. It is positive earth and i have a cut out switch on the battery to solenoid starter line. It is 12v. When I start, the solenoid switch sticks on so the cut off switch acts as starter except it keeps the starter motor running which is obviously to be avoided!! I have tried three different solenoid starter switches and all do the same. All wiring is as per wiring layout. Dash starter not working at moment. Connections to solenoid switch are Negative battery feed plus regulator to one side, starter motor to other and dash starter button to smaller connection between. Managed to get engine running temporarily by introducing another cut off switch on the regulator line and using the other one to switch off feed to starter motor when engine catches! Will try a brand new solenoid to try but feel there is something i am missing (apart from some brain cells!). Ideas? Thanks Nigel Quote Link to comment Share on other sites More sharing options...
David Herbert Posted December 4, 2015 Share Posted December 4, 2015 The only way the solenoid should be able to energise is if there is a circuit through its coil, i.e. through its small terminal, through the coil and then through the big terminal to earth. If you have a wire attached to the small terminal i would disconnect it and put a meter on it with the engine running. I suspect that it either is not the one from the starter switch on the dash or that switch is stuck in the on position. I know that it is not always convenient but it is better to put the cut out switch between the battery and everything else. That way you isolate the battery from all possibility of being flattened by leaving things on or defects and thieves can't start it so easily. It makes no difference which battery terminal you put the cut out to, if it's disconnected on either one, nothing will work. David Quote Link to comment Share on other sites More sharing options...
The Auck Posted December 4, 2015 Author Share Posted December 4, 2015 The only way the solenoid should be able energise is if there is a circuit through its coil, i.e. through its small terminal, through the coil and then through the big terminal to earth. If you have a wire attached to the small terminal i would disconnect it and put a meter on it with the engine running. I suspect that it either is not the one from the starter switch on the dash or that switch is stuck in the on position. I know that it is not always convenient but it is better to put the cut out switch between the battery and everything else. That way you isolate the battery from all possibility of being flattened by leaving things on or defects and thieves can't start it so easily. It makes no difference which battery terminal you put the cut out to, if it's disconnected on either one, nothing will work. David Thanks David I'll try that or sort the dash starter button out. I'm pretty sure its wire is correct so maybe it is stuck on. When I discovered this fault the first few attempts at starting were okay using the solenoid starter switch, but after 3 or 4 attempts it developed the problem mentioned which stayed. I have the cutout switch between the battery and everything else so that is fine. Bad earths on any of the relative components wouldn't cause this would it? I wouldn't think so but just thinking about old vehicles and their electrical problems! Thanks Nigel Quote Link to comment Share on other sites More sharing options...
Richard Farrant Posted December 4, 2015 Share Posted December 4, 2015 Hi Nigel i think the problem is that pushing on the solenoid button manually operates it and not enough pressure causes arcing and welding contacts. Wire in a starter switch and this will cure it. Clean up contacts first. I have seen this before. Quote Link to comment Share on other sites More sharing options...
woa2 Posted December 4, 2015 Share Posted December 4, 2015 Are you sure it's Positive earth? Both my Ford V8s are Negative earth and 12 volt. Quote Link to comment Share on other sites More sharing options...
Richard Farrant Posted December 4, 2015 Share Posted December 4, 2015 Are you sure it's Positive earth? Both my Ford V8s are Negative earth and 12 volt. Robert, I think you will find it was only the British War Office spec vehicles, ie WOA and WOT that were Negative earth, this was because of the CAV charging equipment used, as it was common through a lot of vehicles, inc. Austin and Bedford. As a rule, Fords tended to be Positive Earth and 6 volt on other vehicles. Quote Link to comment Share on other sites More sharing options...
T corbin Posted December 4, 2015 Share Posted December 4, 2015 On the ford GTB the starter button gives the solenoid a earth to the terminal you might try that T CORBIN Quote Link to comment Share on other sites More sharing options...
The Auck Posted December 9, 2015 Author Share Posted December 9, 2015 Thanks everyone Will try these and report back so others may benefit. Talk about frustratingly weird! While I am posting here is another. Have been completing the prop shaft connection to the back axle and midway bearing support, and had to replace the cups on the pinions/splicers i think you call them. Had some new ones and after cleaning the pinion/splicer stub ends, tapped the caps gently onto the ends. A tight fit. When i encouraged the caps, all of them the same, to rotate, they seemed to unscrew one way and then lock, then screw tiģht the other and then lock. How? They are push on. As they unscrewed they left the rod bearings on the stub ends. Prop shaft now fitted and hoping all is well once i get a water pump conditioned and dynamo bearings sorted. Oh the fun of lying on a cold dusty concrete floor as the wind and rain rattle the corrugated sheets on my Nissen hut. Quote Link to comment Share on other sites More sharing options...
The Auck Posted December 13, 2015 Author Share Posted December 13, 2015 Put everything back as it should be, took away my two isolator switches and reversed the wires to the solenoid. Ran a tester across terminals and no reading which is great. Then pushed the solenoid starter and not only did it disengage as it should, it connected to the starter so it seems the problem was that the solenoid was negative earthed. Couldn't start v8 as its water pump is off being refurbished and its dynamo is being sorted too. Thanks for advice everyone. Quote Link to comment Share on other sites More sharing options...
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