GT40s.com
MK-I  MK-II  MK-III  MK-IV  GULF  MIRAGE  J-CAR  LOLA
GT40s.com
Home Forum Gallery Support GT40s.com  
Register FAQ Advertisers Search Today's Posts Mark Forums Read

Go Back   GT40s.com > >

Notices

GT40 Tech - Fueling, Electrics, & Engine Cooling Petrol, Electrons, & Water

Reply
 
Thread Tools Display Modes
Old 24th July 2017, 04:32 PM   #1
johnny cobra's Avatar
johnny cobra
3 Tenths
United Kingdom
 
Join Date: Jun 2015
Location: Essex
GT40: Tornado GT 40.
Posts: 357
Thats strange ...

Hi all . my 40 is almost complete now . been doing final testing of stuff as you do ... Just making sure all is good .... ready for IVA .........so all has been good engine starting and running up nice ..... all lighting good .... body catches ..... fans ... BUT to day I was in the garage tinkering and a strange thing is now happening .. when I turn the ignition key to 1st click ready to press the start button ... and the engine spins over without stopping before I have pressed the start button ....... Do you think it could be a dodgy ignition switch ... Its been fine since the loom and gauges have been fitted .. I just don't understand this ........ Any ideas guys and girls ..

John..
__________________
Tornado 40 330 BHP almost done
johnny cobra is offline   Reply With Quote
Old 24th July 2017, 06:28 PM   #2
jac mac's Avatar
jac mac
I Have No Life
New Zealand
 
Join Date: Dec 2005
Location: Gore, NZ
Posts: 4,316
Re: Thats strange ...

Many years ago when doing engine swaps we found on English cars that the alt warning light did not have enough resistance to trigger the alt to charge when used with USA type alternators with the result that engine would continue to run after ign turned off or kill switch turned off, a small resistor in parallel with warning light or a larger wattage bulb if space allowed was enough to fix it, But your problem might be in the starter button- stuck contacts. As long as battery is connected the starter will engage as soon as power reachs solenoid, work back from that. Also make sure solenoid terminal is not touching live main lead or terminal to starter.

Swap PC to edit this... Ive apparently got an issue with wires running too close to one another on it!!.. The resistor was reqd to make USA Autolite/Motorcraft Alt work with UK Frd wiring looms, Randy is correct, a diode was reqd to prevent run on with USA Alt/UK car wiring on key off or master off. Track safety guys get a bit upset when they hit the kill switch and the engine keeps reving its head/s off!!
__________________
AMGT Rep Steel Mono x Plans, FE328 T44R.
[email protected]

Last edited by jac mac; 24th July 2017 at 10:37 PM.
jac mac is offline   Reply With Quote
Old 24th July 2017, 08:49 PM   #3
Big-Foot's Avatar
Big-Foot
Administrator
United States
 
Join Date: Jan 2007
Location: Kenyon, MN
GT40: Gulf Cart
Posts: 6,602
Re: Thats strange ...

Are you sure that wasn't a diode Jac?

Disconnect the positive wire from the alternator and then the energizing wire (small primary) from the starter solenoid just and check for 12v there when you click the switch to RUN position. If it is 12v, I would suspect the ignition switch.
__________________
Regards - Randy
-- Youth and talent are no match for old age and treachery!
GT40 RCR40 #45 G50-331-Weber IDAs ((Sold))
My build site:
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
Big-Foot is offline   Reply With Quote
Old 25th July 2017, 01:47 AM   #4
IanAnderson's Avatar
IanAnderson
Lifetime Premier Supporter
United Kingdom
 
Join Date: Nov 2003
Location: Ashford
GT40: Dax 40 Mk1 (Rov
Posts: 3,982
Re: Thats strange ...

Are you running a coil that needs a ballast resistor in normal running? Runs about 9 volts and then has a direct feed from starter during cranking to give a better spark to start?

If connected to wrong terminal on the starter the bypass wire can back feed and energise the starter solenoid.

Ian
__________________
DAX GT40. Morgan 3.9 EFi, Worked by John Eales.
Renault Box, Always makes me smile!
IanAnderson is offline   Reply With Quote
Old 25th July 2017, 02:40 AM   #5
johnny cobra's Avatar
johnny cobra
3 Tenths
United Kingdom
 
Join Date: Jun 2015
Location: Essex
GT40: Tornado GT 40.
Posts: 357
Re: Thats strange ...

Thank you guys you are all great.....Ian no ballast resister fitted m8 ....Jac and Randy will give it a look a bit later today .....
Thank you again John..
__________________
Tornado 40 330 BHP almost done
johnny cobra is offline   Reply With Quote
Old 25th July 2017, 05:13 AM   #6
saxoncross's Avatar
saxoncross
8 Tenths
United Kingdom
 
Join Date: Mar 2007
Location: Norfolk, UK
GT40: Tornado
Posts: 825
Re: Thats strange ...

Hi John,
I would be looking for stuck contacts in your starter switch. As I don’t believe you’ve a relay on the starter to solenoid line, it could have fused the contacts, especially if it’s a reproduction one
Regards,
Andy
__________________
Failure is not an option, but cock-ups will happen
saxoncross is offline   Reply With Quote
Old 25th July 2017, 01:57 PM   #7
johnny cobra's Avatar
johnny cobra
3 Tenths
United Kingdom
 
Join Date: Jun 2015
Location: Essex
GT40: Tornado GT 40.
Posts: 357
Re: Thats strange ...

Hi Andy m8 hope you are well .. I did think the same . I am going to disconnect the starter button over the weekend . See what happens . Will let you know how it goes ...
Thanks for your reply m8 ..

John.
__________________
Tornado 40 330 BHP almost done
johnny cobra is offline   Reply With Quote
Old 23rd August 2017, 12:19 PM   #8
johnny cobra's Avatar
johnny cobra
3 Tenths
United Kingdom
 
Join Date: Jun 2015
Location: Essex
GT40: Tornado GT 40.
Posts: 357
Re: Thats strange ...

Dodgy starter button .... Thanks all .

John...
__________________
Tornado 40 330 BHP almost done
johnny cobra is offline   Reply With Quote
Old 23rd August 2017, 04:58 PM   #9
saxoncross's Avatar
saxoncross
8 Tenths
United Kingdom
 
Join Date: Mar 2007
Location: Norfolk, UK
GT40: Tornado
Posts: 825
Re: Thats strange ...

Hi John,
Glad you found the route cause of the issue. Wire in a relay so you don't get a repeat failure, even if you get one with a higher current rating.
Rgds,
Andy
__________________
Failure is not an option, but cock-ups will happen
saxoncross is offline   Reply With Quote
Old 24th August 2017, 12:18 PM   #10
johnny cobra's Avatar
johnny cobra
3 Tenths
United Kingdom
 
Join Date: Jun 2015
Location: Essex
GT40: Tornado GT 40.
Posts: 357
Re: Thats strange ...

Thanks Andy m8 ... Will do ....

John...
__________________
Tornado 40 330 BHP almost done
johnny cobra is offline   Reply With Quote
Reply

Tags
engine, good, ignition, ready, strange


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

 
Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

Forum Jump


All times are GMT -4. The time now is 08:58 AM.