101 coil questions

Good feeling isn't it!

What's the spark like?

Oh yes indeed! It took me ages to fit the king lead, due to me only having the standard number of joints in my arm.

Not sure. I don't think mine is standard anyway - it came with the flashy dizzy.

I think it's pretty common on early Range Rovers, and therefore it doesn't surprise me that the 101 has one. My feeling with ignition parts (having had so much grief with ignition systems in the last 12 months) is that it's easier and cheaper to replace the whole bloody lot in one go than pfaff with a bit at a time.

Fit a remote fuel pump while you are doing it!!! :-)

Ballast coils are usually designed to run at 9v. The coil normally runs through the resistor, except when cranking. There are two wires to the coil, one from the ignition on position, via the ballast, and one direct from the starter solenoid (or ign sw start) direct to the coil. So if you remove the wire from the ballast resistor you should get the full 12v, less at the coil itself.

It's possible the resistor is knackered.

Alex

It does sound like the ballast is the problem then, as it ran fine when it was cranking, but died as soon as i turned the key back. Or maybe the wire that runs to the ballast resistor.

How happy will my coil be running at 12V?.

If i replace the coil with one designed to run on 12V, can i dispense with the resistor totally?, or does it have some higher purpose?

yep :). It was improved once the wheels had gone circular again, and once i'd worked out that the torrent of liquid running off the fuel tank was just the swimming pool draining out of the interior.

Once ive got the leaks sorted i've got to take the son of the owner of where its living at the moment off-roading round the fields. apparently he has some nice mud holes. Thats some good incentive to get it done! :)

Well it ran well yesterday, so it cant be that bad! did about 20miles in it and managed to keep up with my mate as he thrashed his LWB 2.25 petrol down the lanes.

My mate offered to snap my arm a few times so that I could actually get at the coil. I think I shall relocate it somewhere a bit more convenient..

hopefully i can put a different coil on and dispense with the resistor.

No problems with the fuel pump yet. I can say that cos the 101 isnt here to hear me...

"> If i replace the coil with one designed to run on 12V, can i dispense

I think that's what was done to mine, It's run fine ever since. On the other hand, I think a Balast resistor must cost less than a new coil ?

Pete

The idea behind the ballast resistor coils is to improve the sparks whilst cranking. The few LandRovers I've seen crank remarkably poorly and start even worse. I would recommend one of two options either retain the ballast resistor system replacing any defunct/suspect parts or install a replacement electronic system. If the former check first that you are getting 12V at the coil when ignition on but not cranking, this will go towards eliminating failure at the starter solenoid and/or the ballast resistor itself, which may be installed at, near or even in the starter solenoid.

-- If Your specification is vague or imprecise, you'll likely get what you asked for not what you want

Tom,

Something else to consider, given you mentioned wiring the other day.... is the battery charging from the alternator.. If it's not then this will have a similar effect as the Battery literally discharges the engine will eventually splutter to a halt.. Provided there is an output from the alternator then there should be no problems though. If you've continued to run for some time on the same battery then I would completely discount this theory though.

I had this problem on an Old Astra GTE when I were a lad. That'll teach me to polish the engine!

Lee D

The ballast resistor is there to drop the voltage to about 6V ish when running normally. When you're cranking the engine the resistor is bypassed, relying on just the volt drop due to the load of the starter motor. It gives a better spark on starting. It should be fitted with a 6V coil, and running it on 12V will probably kill of your coil in a few hours due to overheating... Your poor voltage may well be coming from dodgy connections on the resistor itself, or somewhere else down the line. You could either replace the coil with a 12V one and ditch the ballast resistor, or sort out the wiring and use the resistor and have better starting. It's unlikely the ballast resistor itself has gone. They're rated to a higher power than the coil will draw, and fail open circuit. I'd give it a test with a multimeter if there are no problems with cabling/connectors. The resistance should be printed on it 150R rings a bell?

Andy

Thanks everybody. I now see the point in the ballast resistor.

Had a talk to my dad who said that his resistor-less morris used to be a pain as it was either hard to start when the voltage dropped, or used to burn out the coil fairly quick due to it being over-powered.

I shall have a good look and see if theres any chance of actually seeing/reaching the resistor or any of the relevant cabling on the 101 with the compressor there.

If not then I shall probably stick one of the pile of coils out of the garage/shed on and run it at 12V until i manage to fix the proper stuff (when i get it back home and take the compressor off probably)

Mine is a pig to start from cold (10-30 seconds cranking on full choke), but once going it's absolutely fine and starts before you can even hear the starter motor. Is this because I have a 12V coil and no ballast resistor?

The rest of the wiring in the truck is pretty past it, so this wouldnt surprise me. A fair bit of my dash doesnt work, or flashes when it shouldnt, the voltage gets lost somewhere on the way to the headlights, and theres such big bundles of wires that theyve been rubbing on the alternator (before i got it).

Tis not in the easiest place to see on a 101! :)

Even this weekend, after being sat for close to 5 months mine started almost instantly (that was before the coil/resitor played up).

Took about 20-30 secs for all the cylinders to kick in properly, but it was running well enough. It didnt need all the choke, and It would go most of the way in almost instantly.

Your fuel pump isnt through the pressure switch anymore is it?. Mine is independant and i gave it a few secs to build some pressure up before i started it.

That could be a possibility. There's a fair bit more current draw on cold cranking. Couple of other things aside from the usual suspects (HT leads/cap etc):

If you've any vacuum pipes from the inlet - ie rocker breathers / brake servo that aren't properly sealed initial starting is bad to to incorrect manifold pressure. Make sure the oil filler seals too!! Had this prob on a Triumph a while back.

Also if you haven't given the fuel pump chance to get fuel to the carbs before cranking.

With my RR , running on a 12V coil without ballast resistor for a bit, starting took longer than before, so once you've discounted the other options I'd have a go with the coil. If the wiring's not already there, you want a feed through the ballast resistor when the ignition's on, and a feed to the coil direct from the starter motor bypassing the resistor.

Have fun

Andy

I can guess...

Probably find corroded connectors are the culprit. Give them a good rub down

• a bit of copper grease.

Andy

On or around Tue, 20 Apr 2004 23:41:03 +0100, Tom Woods enlightened us thusly:

if you run a 12V coil on a ballasted system, you'll not break anything. If the ballast bit is working, you'll get poor sparks when running, or maybe none.

when cranking, if the ballast is being switched out, you'll get normal

if you run a 12V line to a 6V coil you'll not do the coil any good - remember that when charging, it's up to about 14.5V, so if you run a separate coil supply then you need to put a 12V coil on it.

have you checked voltage when cranking? If you have a ballast resistor and it's working, then the voltage at the coil should go up to about 9V or so while cranking, i.e. while the solenoid is engaged.

Never had all that much trouble staring my V8 on LPG with plain 12V system, even when it had a points distributor, unless it was wrong in some other way.

Morph used to do this, It was due to having the fuel pump wired only to go live when the oil pressure switch was closed circuit. Then the float chambers need to fill after which it started... but it was a PITA so I removed it and assume if the oil pressure light comes on I will check unlike the squaddies who clearly couldn't give a hoot.

:-)

Lee D

-- ________________________________

In message , Andy Warner writes

... or like mine, if the motor stands for a few hours the lifters bleed down and the engine needs cranking until it gets about 15psi of oil pressure which pumps up the lifters and she fires ... every time. If the lifters are already pumped up she'll fire on the key ... every time. High bleed lifters are notorious for bad starting but have their benefits.

Naturally, sods law means the thing will not start when I walk outside ...

On or around Fri, 23 Apr 2004 13:43:28 +0100, AJG enlightened us thusly:

I've an idea the V8 is very empathic, and knows when you're at the stage of assuming that it's gonna fire straight off, and then doesn't just to keep you properly respectful.