Electrical problems

[Sarah Ryan]

Hi I decided to replace the dash board lights on my Sprint. I had to remove the Tacho to get at the Fuel guage. I did not remove any of the leads on the back of the Tacho I left the lead from the voltage stabiliser intact as well as the lead from the Luminition. I put the Tach back in place along with the earths that were there attatched to the securing thumb screws.

Problem is when I went to start it it would not fire but gave a half fire when the ignition ket was coming off the start position. Any ideas!!

[steveww]

The ignition feed to the coil goes through the tacho. My guess is that one of these wires has fallen off while you were in there. Double check the wiring for loose connections.

[Sarah Ryan]

Thank you for responding. Looking at the back of the Tacho I have three spades coming out of the unit. One is -ve one is + positive & the one takes the Brown wire to the Luminition. Have i missed something

Sarah

[twincamman]

Sahra ----Im doing this job on my newly purchased europa restoration project ---- and learned from doing the elan that the job is much easier to remove the whole dash ----the removal is simple and allows wiring while sitting comfortably -and with good visability ----ed

[tvacc]

Yes....look for the white leads. They go into the tach and then back out to the coil and dist. You probably knocked it off. Been there and done that. Once on trip through the NW USA and it was getting dark. I saw my light had fallen out of the tach..reached in and plugged it back in and the car would not start. Took all night to figure it out.

Tony V
www.lotusowners.com

[john.p.clegg]

Gave a half fire when the key was coming back?
Sounds like either a duff battery(not enough volts to crank and spark) or no power to the coil when cranking-something to do with the ballast resistor?
John

[Sarah Ryan]

Hi Guys, thank you for the responses. Taking out the dask would send my nerves out the door, no not again. There are no white wires going into the tacho. Just one lead from the voltage stabiliser that looks like +ve one for negative that attatches to the tacho body & one lead going to the Luminition. I belive the original Smiths internals may have been changed for VDO
Battery OK The car just hates me!

[twincamman]

no emotions involved Sarah -just ohms law vs the prince of darkness -- --ed

[denicholls2]

John wrote:

Gave a half fire when the key was coming back? Sounds like either a duff battery(not enough volts to crank and spark) or no power to the coil when cranking-something to do with the ballast resistor?

Indirectly, yes. Indications are that something (most likely the wire referenced) is wrong with the circuit that bypasses the ballast resistor for starting.

When starting, the resistor is bypassed and 12 volts is applied to the coil. When running, a separate circuit engages the resistor. This second circuit is clearly working properly, while the first is not.

In any event, the solution is to ensure that 12 volts somehow gets to the coil only while starting the engine. Best way to do this is to troubleshoot the referenced circuit between coil and key switch.

[Sarah Ryan]

Hi & thank you all for your help. No more broken nails or blood pressure tablets. Ive called in the mobile sparkie to sort it out. If he cannot fix it I'll post a phot of the bon fire!

[Sarah Ryan]

Thank you to all who have lent a hand to solve my naughty Sprint. The mobile electrician arrived with a testing gadget & solved the problem in two minutes. As I was advised in the above posts it was a lead that was inplace but the spade came off the terminal but looked like it was in place. Car & I are a happy item again. Thanks again, weekend coming up hope the weather is fine in Sydney.