Starting (or not!) on cold mornings!

Post by **Kevin** » Sat Oct 21, 2006 11:35 pm

If you edit your profile you can fill in your location.
You need to speak to HarryMango on here (rog) as he is in Leicester and an active local branch member and should be able to give you some local info, there is also a local specialist called Minorite but I have not seen their ads for a while.

Post by **Furrtiv** » Sat Oct 21, 2006 11:41 pm

Thanks for the info - I use Minorite all the time (well, it's Houghton Garage that does mechanical stuff, Minorite is their other branch for bodywork in Billesdon). I'm in Oadby, if that's any help to people here?

Post by **Furrtiv** » Sun Oct 22, 2006 2:08 pm

Right, I have news to report!
I've just had a friend come over with some meters to help me read what the battery's doing.
At idle, the battery is giving out 12 and a half volts. With both heater and lights on, it dropped to 11 and a half.
Before running the engine, the battery was reading as only 29% charged, then the meter decided that it was a bad battery (but the friend thinks that this may have been due to the fact that it was grossly undercharged). After running the engine on idle for five minutes, with no electricals on and no other noticeable drains, it was okay, reading at 12 and a half volts again.
So it seems, to my friend (who admits that he doesn't know anything about dynamos) that the dynamo isn't giving the battery a good enough charge, or that the battery isn't holding the charge and is discharging. However, with everything including the engine switched off, the reading for the discharge was zero, so no parasitic discharging going on. Ultimately, it does appear to be the dynamo at fault. But as neither of us are dynamo experts, I'm open to other suggestions.

Post by **Onne** » Sun Oct 22, 2006 2:50 pm

If you check your dynamo for its output, you should rev the engine a bit.
Modern alternators are designed to charge at all revs, this is not the case with the good old dynamo.

Onne

Post by **alex_holden** » Sun Oct 22, 2006 4:47 pm

Yes, you should measure the battery voltage when the engine is running fairly fast, both with and without the lights and accessories turned on.

Post by **Furrtiv** » Sun Oct 22, 2006 6:02 pm

Okay, more news to report! The car died on the way back from the supermarket - lights, ignition, everything went dead. So, after a close inspection by the RAC man (who arrived very quickly!) and a battery of, er, battery tests - it was decided that the dynamo was most definitely to blame. So it looks like I might be going for an alternator conversion after all.

Post by **bmcecosse** » Sun Oct 22, 2006 10:01 pm

No point checking when it's idling - it's got to be revving. Usually the RAC will immediately sell you a new battery at vast expense - they get commission! First check the fan belt is tight enough - I assume MrRAC tightened this for you ? Then - meter again - this time while revving. Dynamos are very reliable - it probably just needs new brushes which cost very little and are easy to fit.

Post by **alex_holden** » Sun Oct 22, 2006 11:26 pm

If you can fix the dynamo yourself then that's obviously the cheapest option - a pair of new brushes (if it needs them) is only about three quid. I'd expect it to take an hour or two if you already have all the necessary tools to hand and you don't run into any unforeseen problems like seized bolts and rounded-off nuts. If you get a garage to do it for you instead then there's a roughly similar amount of labour involved in servicing your dynamo vs swapping it for an alternator, but if you went for the alternator upgrade you would have to buy the parts too. You might be able to find a cheap second hand one on eBay or in a scrapyard if you're lucky, but if not then a full kit of new parts is about seventy quid.

Post by **Chris Morley** » Sun Oct 22, 2006 11:51 pm

What about the red ignition light in the speedo? You should see it go out after starting when you rev the engine and it should glow faintly when the car is ticking over. You need to run the engine at well over 1000rpm to start recharging.

it was decided that the dynamo was most definitely to blame. So it looks like I might be going for an alternator conversion after all.

That's a bit like replacing an engine because the sparkplugs are knackered. Fundamentaly the dynamo should work as designed, so fix that. The dynamo is probably just in need of a new set of brushes & cleaning. However if you aren't confident doing this you could simply get a reconditioned dynamo from a specialist like ESM and swap them over (30 minutes work). Changing to an alternator involves a lot more work and the conversions available seem to be of rather questionable reliability.

The starting handle can save you when the battery is somewhat run down but it won't help if the battery is almost fully discharged. When a battery is badly run down the dynamo can't ever recharge it enough - hence the need to use an overnight recharger. Works fine for me when I do lots of short journeys in Winter.

The one thing that causes most of these problems is the lack of enthusiasm to start up on a cold winter morning.

Some years ago I had this. Nothing wrong with the dynamo or battery. Turns out the starter motor was on its way out and it drew a huge amount of energy as it slowly turned the engine. A new starter sorted the problem. Try this: recharge the battery overnight then try to start it with the starting handle - if it fires more quickly than on the key it may point to the starter as your problem.

Post by **stevey** » Mon Oct 23, 2006 9:25 am

are you sure its teh dynamo and not the regulator on the bulkhead, brothers wouldnt start in the mornings as the regulator wasnt allowingg the dynamo to charge the battery. red light on all the time

Post by **Furrtiv** » Mon Oct 23, 2006 5:55 pm

Not sure at all now what it is - I've booked it in with my local garage, a Minor specialist, and asked them to investigate first, discover what the problem is, and then get back to me. I've currently got a friend giving me a lift to and from work.

Post by **bmcecosse** » Mon Oct 23, 2006 7:03 pm

OMG - Minor 'specialist' !! But are they any good?

Post by **Furrtiv** » Mon Oct 23, 2006 9:14 pm

Um, yep, been taking my Minors there for years!

Post by **Pyoor_Kate** » Thu Oct 26, 2006 3:11 pm

Sadly I'm old enough to have gone through quite a few winters driving cars with dynamos in the days before alternators became standard fitting and can assure you I didn't suffer constantly flat batteries

I have to disagree; not that you didn't suffer constantly flat batteries, but that dynamos are absolutely fine whatever in modern traffic conditions. Whilst it does sound like the charging system on Furrtiv's car has an issue which needs sorting - and will probably fine for the driving Furrtiv does - when my beloved first returned to the road winter driving (consisting as it did for me of a daily commute with 45 minutes of sitting in stationary traffic in Bristol) left me with flat battery syndrome repeatedly.

Although the charging system was quite able to cope in normal conditions, with the long period of almost stationary traffic I was frequently forced to turn off both the wipers and the heater as at idle, the dynamo's output was simply too low. Although this problem was resolved by fitting an Alternator, I wouldn't describe my alternator based experience as one of great joy; I've got through a vast number (to be fair, the first one that was fitted was faulty on fitting) and have found them much less reliable than the old dynamo...

Post by **bmcecosse** » Thu Oct 26, 2006 7:17 pm

You could just have put a smaller pulley on the dynamo - and lifted the idle speed slightly. However - 45 minutes of stationary traffic would drive me nuts - my commute is 15 miles and if it takes more than 20 minutes I get anxious! 15 minutes is the norm.

Post by **Furrtiv** » Thu Oct 26, 2006 8:28 pm

My daily commute in the Traveller is about thirty miles all round, and there is a bit of sitting idle if I get out of work too late to avoid the rush hour crawl at Fosse Park in Leicester! I never thought to switch off my lights when queuing, somehow it struck me as a bad idea, but the windscreen wipers do seem to be doing the worst for draining, and I used to have an intermitent switch for them but it's stopped working so I'm back to the one-speed wipers for now.
Also, the battery has at least twice been totally flat when I've had to charge it before, and a couple of people I know reckon that it can cause damage to a battery to allow it to fully discharge - is this true?

Post by **Furrtiv** » Thu Oct 26, 2006 8:29 pm

My daily commute in the Traveller is about thirty miles all round, and there is a bit of sitting idle if I get out of work too late to avoid the rush hour crawl at Fosse Park in Leicester! I never thought to switch off my lights when queuing, somehow it struck me as a bad idea, but the windscreen wipers do seem to be doing the worst for draining, and I used to have an intermitent switch for them but it's stopped working so I'm back to the one-speed wipers for now.
Also, the battery has at least twice been totally flat when I've had to charge it before, and a couple of people I know reckon that it can cause damage to a battery to allow it to fully discharge - is this true?
Oh yes, fifteen miles hereabouts can take anything up to forty-five minutes! Blinkin' roadworks!

Post by **bmcecosse** » Thu Oct 26, 2006 9:08 pm

Yes - flattening the battery is a very bad idea - they don't like it!

Post by **nebogipfel** » Thu Oct 26, 2006 9:14 pm

Pyoor_Kate wrote: I have to disagree; not that you didn't suffer constantly flat batteries, but that dynamos are absolutely fine whatever in modern traffic conditions.

So you don't actually disagree then Kate

My point, really was that in the days before alternators cars didn't all regularly grind to a halt.

I take your point about long waits in traffic but as BMC says increasing the rotation speed of the dynamo so it is charging all the time should solve the problem.

Post by **bmcecosse** » Fri Oct 27, 2006 7:22 am

BUT - may compromise it's life if you also run the engine at high revs! One advantage of the alternator is that it CAN be run at high revs - hence it has a smaller pulley to provide some (but not full capability) charge at a reasonable idle speed. But even on modern cars this still needs to be almost 1000 rpm - modern ecu systems automatically pick up the idle speed if the car's volts are too low.