Starting 2a petrol

Cal110 · Nov 12, 2019

Thanks for all your advice. Sorry if this is very basic stuff! I changed the battery with a friends new one and didn’t start. I’ll attach images of earth and battery cable...

tacr2man · Nov 12, 2019

Cal110 said:
@Disco1BFG but is it not strange that noting turned over when I was jumping?

At 11.9 volts the battery is only at 40% capacity , and would need a good set of jump leads from another vehicle with engine running at good level to bring battery voltage up before trying to turn over on starter.
Having boosted the battery for say 10 mins try to start by button /key . If it wont turn over , look at solenoid and check red/white wire is connected . If connected , remove and use test light to see if getting 12v at end of wire when assistant pressing start /key. If not getting supply 12v at end , then look further back in circuit , to see why no 12v on red/white wire . If there is 12v at end of red/white wire then you need to check solenoid is working , looking for 12v on large terminal going out from solenoid to starter motor.

Disco1BFG · Nov 12, 2019

Cal110 said:
View attachment 193973

Well, niether of those "connections"

is going to be helping much

Dorset_dumpling · Nov 12, 2019

Those cables don't look great. It is important that your wiring is in as good condition as possible. Corroded and poorly connected wiring is one of the most common causes of electrical problems. This may be the ideal time to renew some of your ignition wiring, particularly as this is the wiring that carries the highest current and even a relatively small drop in voltage and current will cause starting problems.

Disco1BFG · Nov 12, 2019

@Cal110 - you need some new battery cables, pronto....

Have a nosy here for an indication of price and availability

www.ebay.co.uk/itm/202511294259

Cal110 · Nov 12, 2019

I looked at the ignition coil. Green wire from distributor / condenser to ignition coil on the negative input of the ignition coil. Black wire going to positive (removed for photo purpose). Is this the correct direction?

Disco1BFG · Nov 12, 2019

Ignition coil function and wiring explained here:-

https://en.wikipedia.org/wiki/Ignition_coil

Have you got it turning over yet ?

steve2286w · Nov 12, 2019

Your colours don’t match to manual wiring diagram which is ignition white wire to +VE on coil with -VE to distributor in white/ black wire , your colours different but sound connected correctly

have a read here may help too
https://www.landyzone.co.uk/land-rover/series-3-petrol-wont-start.352433/

Cal110 · Nov 12, 2019

@steve2286w thanks for this accurate answer, glad to hear it was wired correctly.

I’ll have a look at your link - thanks.

Cal110 · Nov 12, 2019

@Disco1BFG noting yet! I’ll have another go once I get new leads. I’m assuming you will want a volt reading input of 12.5 into the ignition coils to creat a spark?

And thanks for the eBay link

kermit_rr · Nov 12, 2019

A healthy, regular lead acid battery is considered only 50% capacity at 12.2 volts. Anything less than this and I'd be very surprised if there's enough energy to turn an engine over at sufficient speed to start, if at all.
It's also important to measure the voltage while the starter is engaged, this will give a good indication on the battery health, assuming it's been fully charged first.
Get the earth/battery cables sorted first and see if you can get it turning over at a reasonable speed. Worry about sparks and fuel later

Trench Rat · Nov 13, 2019

Cal110 said:
Ive already replaced the cap and condenser - haven't replaced the contacts.

I know i saw you wrote that. What i'm saying is that it's worth checking if you even need to in the first place by seeing if the engine starts on the handle, hence troubleshooting.

For future troubleshooting.

Cal110 · Nov 13, 2019

Thanks for everyone’s help and comments. Think I may have resolved the issue

Changed the earth terminals.

Got a crank start handle and managed to fire the motor up for a few seconds, just before I had time to pull the choke it cut out.

Wired a positive connection directly to starter motor and turn engine over a bit.

Removed solenoid cove caps and placed a screw driver over to bridge this and got the starter to move. Currently charging the battery to get it over 12.5 to see if it will fire the motor up.

Question: should I have the ignition turned on when bridging the solenoid on start up? I’m guessing yes.

Disco1BFG · Nov 13, 2019

Cal110 said:
I’m guessing yes.

Only if you want it to start

If you read the link I posted above ( https://en.wikipedia.org/wiki/Ignition_coil ), then it half explains the why's and wherefores.... ( which is why I posted it

) - there's some good stuff on wikipedia - specially on the basics of how stuff works ... worth a read

rob1miles · Nov 14, 2019

Re battery leads. They really matter so take time to get them right. Clean the ends and once they are in the clamps get a blowlamp and fill them up with solder. Solder up the flat termial ends too. Clean the chassis where the earth lead goes. It hleps to run 2 earth cables, one from the battery to a bolt ont he starter and one from the same bolt to the chassis. The starter will draw 400 amps so any bad connections make a huge difference.

TheMegaMan · Nov 14, 2019

@rob1miles That's an interesting comment about 2 cables. My Landy had as you describe - a lead from the chassis to the starter motor, plus a long braided earth strap from the batter that ran around the engine bay, about 2m long. I was going to omit the additional strap on the rebuild, thinking the chassis should be able to provide enough capacity, but now you've got me thinking I should replace it.

Any idea where to buy such long lengths? I can only find leads up to about 2ft so far (unless I want to spend nearly £90 on 5m of the stuff!)?

Dorset_dumpling · Nov 14, 2019

You don't need an earth strap that long. Shorter is better as a longer cable means more resistance and a bigger voltage and current drop. Just use the shortest one that will work.

Cal110 · Nov 14, 2019

Yep - I’ve got two earth points one to the body and one to the engine block. Another earth from the starter to the chassis.

Charged up the battery and was able to start the motor this morning bridging the starting solenoid.

Thanks everyone for the comments and advice!

TheMegaMan · Nov 14, 2019

Dorset_dumpling said:
You don't need an earth strap that long. Shorter is better as a longer cable means more resistance and a bigger voltage and current drop. Just use the shortest one that will work.

Yeah, I understand that. But with the battery one the opposite side of the engine to the stater motor, it needs to be about that long to get around the block - certainly over 1m. But I suppose as long as I earth the block to the battery, actually the starter motor already has its second path without needing to run a lead directly from starter to battery...

Disco1BFG · Nov 14, 2019

TheMegaMan said:
Any idea where to buy such long lengths?

I posted a link to an evilbay listing for bespoke battery cables, above

Shorter is better - it only needs to be long enough to do the job, and long enough to cope with any relative movement.

If you have a local wagon spares place, they'll have all sorts in stock.... You can guess how I know this

My D1 has three earth straps - one from batt -VE to body and onto chassis. Batt -VE to engine block, and chassis to transmission... ( this is there to avoid the dire consequences of the handbrake cable becoming an earth return

)

Starting 2a petrol

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