Retroanaconda Posted October 28, 2008 Share Posted October 28, 2008 Well it appears to be snowing here in Stafford for some obscene reason, and so this has prompted me to ask about something that's been bugging me about my Defender. When it's cold in the morning, it seems very reluctant to turn over and does so very slowly before just about kicking in. Once it's running it runs fine, if not a little lumpy to start with (but I assume this is just a trait of a 16-year-old diesel engine in the cold), after a few minutes it is smooth as ever. My immediate thought of course was the battery, as I know they don't work as well when cold, and mine is only a cheap Halfords one. Not even a 'heavy duty' Halfords one at that. I got the multimeter out and found that before I turned anything on the battery was reading 12.1V. I'm no expert, but I thought batteries were supposed to read around 12.5-12.6V when fully charged? Or is it just because it is cold? At ignition stage two it dropped to 11V or so. Once the engine was running the alternator built it up to around 13.5V on tickover and 14.2V at normal driving speeds. As far as I know this is fine in terms of alternator output voltages. Then, once I'd had a drive around in the snow (and puddles ) and the engine was up to temperature, I switched it off and watched the voltage fall back down as normal. It then started on the first turn of the key. So this makes me think that it is one of two possibilities: 1. The battery doesn't have a good enough C.C.A rating and is copping out when cold, being warmed by the charging process, and then working fine on second start. OR 2. The battery is actually okay in terms of C.C.A. but is being discharged for some reason, however I feel this is less likely due to the fact that it's only started doing this as it's got colder. We've yet to have a day warm enough for me to try and start it and observe it's behaviour. Any ideas guys? Many thanks Quote Link to comment Share on other sites More sharing options...
western Posted October 28, 2008 Share Posted October 28, 2008 try cleaning the terminals on the earth leads at the connections to engine block/chassis & gearbox. Quote Link to comment Share on other sites More sharing options...
Retroanaconda Posted October 30, 2008 Author Share Posted October 30, 2008 Heh, well before I had a dry enough day to want to be crawling around on the floor under the truck...it's completely let me down today. Didn't have enough charge to turn her over and fire up So tomorrow I guess I'm off to the battery shop, there's a battery specialist reasonably nearby...am I right in assuming I should just get the biggest (in terms of CCA and capacity) I can fit in? Quote Link to comment Share on other sites More sharing options...
western Posted October 30, 2008 Share Posted October 30, 2008 I'd find out if your battery is cream krackered first & have the charging system checked then go for the biggest CCa battery that will fit. Quote Link to comment Share on other sites More sharing options...
Milemarker Type S Posted October 30, 2008 Share Posted October 30, 2008 I would be casting suspicious looks at the starter motor... after checking that it was well earthed by running a jump lead from the starter securing bolt direct to the battery. Quote Link to comment Share on other sites More sharing options...
Retroanaconda Posted October 30, 2008 Author Share Posted October 30, 2008 Well I shall have a look underneath tomorrow (supposed to be dry), and look for dodgy earths and other connections. Ralph, is testing the charging system something that I can do, or is it a specialist job? Cheers Quote Link to comment Share on other sites More sharing options...
western Posted October 30, 2008 Share Posted October 30, 2008 I'd leave it to a auto electrical place, have a look in the phone book for a local one. Quote Link to comment Share on other sites More sharing options...
upnover4x4 Posted October 30, 2008 Share Posted October 30, 2008 Sounds like the battery to me. When your engines cold, most the oil has dripped to the sump & left all the moving parts generally not so well lubed. Additionally the viscosity of the oil means that its in a thicker state when its cold increasing friction & the additional draw on your battery when you turn the engine over. Once youve managed to start the engine everything ok again till the next morning when you go thru the same process. Get the specific gravities checked on the battery. Hydrometers dont cost much & they allow you to check each cell is in a comparitive state. You may find the levels are low even. The plates should be covered but not overfilled. I work on big engines on the trains, & weve got a saying, "give it time ,let it prime". A well primed engine will always start over an engine which has not had oil pumped around it properly. hence why it always starts once it has fired up. Hope this helps Adrian Quote Link to comment Share on other sites More sharing options...
Retroanaconda Posted October 30, 2008 Author Share Posted October 30, 2008 Cheers guys, will have a look tomorrow and see how I get on. Thanks for the help so far, will let you know how it goes Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted October 30, 2008 Share Posted October 30, 2008 You can check the charging system with a £5 multimeter, anything that read volts really. You should be seeing between 13.4 and 14.4 volts on the battery when the engine is running (alternators vary, some are 13.4, 13.8 or 14.4). If you have good voltage at the alternator but not at the battery, suspect the cable between the two, or the earth strap which would also cause poor starting. Most decent battery places (EG not Halfords / Kwik Fit) will have a battery drop tester which will tell you if yours is knackered or not, I'd very much expect them to do it for free at the prospect of flogging you a new one. Quote Link to comment Share on other sites More sharing options...
Retroanaconda Posted October 31, 2008 Author Share Posted October 31, 2008 Checked the earth straps today, and all seems to be well. They're all in good condition, and there is good continuity between the battery negative post and anywhere on the truck's body. I got 13.5V - 14.2V from the alternator when it was running the other day, measured at the battery terminals, so I think that's okay. I will jump if off another vehicle, and then drive to the auto-electrical place in Tamworth and get them to test my battery for me. Quote Link to comment Share on other sites More sharing options...
santalars Posted October 31, 2008 Share Posted October 31, 2008 Good batteries will have a live of 5 to 7 years if well maintained. This means that the acid level never dropped below minimum and they haven't been dicharged by more then 50% of their capacity. Discharge of more then 50 % or even more ("batterie empty") will destroy any lead/acid battery fast. My experience is that the battery is gone after approx 5-7 times full discharge. Gel batteries (eg optima) perform better and they are not that sensitive for complete discharge. (However, they are expensive) Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted October 31, 2008 Share Posted October 31, 2008 Cheapo heavy duty truck batteries are also less sensitive to heavy discharge as the are designed to crank over large diesel engines. (Heavy discharge? See a doctor! ) Quote Link to comment Share on other sites More sharing options...
reggie Posted October 31, 2008 Share Posted October 31, 2008 The same thing happened to my battery in the beginning of the week, I knew it was a little old & weary but couldn't be bothered to change it for the good one I had in the garage as I was in a hurry. Drove to my destination & stayed over, the next morning it nearly let me down, only just started. I won't make that mistake again........... Quote Link to comment Share on other sites More sharing options...
Retroanaconda Posted October 31, 2008 Author Share Posted October 31, 2008 Well, the man with the machine told me that while the battery was in fine condition (and charged, thanks to the journey there), it wasn't beefy enough to supply the amps needed, especially with the cold temperatures. Looks like I'm in the market for a new battery! Quote Link to comment Share on other sites More sharing options...
Sean Posted October 31, 2008 Share Posted October 31, 2008 Looks like I'm in the market for a new battery! dont go to halfords for it - just find your nearest agricultural supplier and ask for a tractor battery (the biggest one that will fit) Quote Link to comment Share on other sites More sharing options...
Retroanaconda Posted October 31, 2008 Author Share Posted October 31, 2008 That's my plan, although I'm tempted by... http://www.devon4x4.com/component/option,c...howcaticons,yes Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted October 31, 2008 Share Posted October 31, 2008 That's very bling but it's a lot of money for not much capacity - unless you're winching with an electric winch you don't need deep-cycle capability. I bought a Vartra silver battery that's 110Ah (twice the one you posted) for around £110 from my local battery place. Quote Link to comment Share on other sites More sharing options...
Retroanaconda Posted October 31, 2008 Author Share Posted October 31, 2008 Thanks Fridge, I will pop to these guys tomorrow and get one similar http://www.autoelectrical.co.uk/batteries.html Quote Link to comment Share on other sites More sharing options...
Retroanaconda Posted November 1, 2008 Author Share Posted November 1, 2008 Well this is the battery I've ended up with: It's a Trane T16, capacity of 95 Ah and a CCA rating of 680A (EN). Cost me £115 including VAT, which is much better value than the Halfords ones...which are £100 odd for something nowhere near as big capacity-wise. Hopefully it should do the job a lot better than the previous one (which is now going to serve as an airsoft-gun-battery-charger ), it's got a good healthy 12.7 volts on it now, but the real test will be tomorrow morning when I go to start it at ten-to-eight. Quote Link to comment Share on other sites More sharing options...
upnover4x4 Posted November 2, 2008 Share Posted November 2, 2008 Well, did it start ok???? Adrian Quote Link to comment Share on other sites More sharing options...
Retroanaconda Posted November 2, 2008 Author Share Posted November 2, 2008 It did indeed. Didn't bat an eyelid, wasn't as cold this morning as it has been though. Typical that we get a warmer spell now ¬_¬ It also held up today being while started, driven a mile or two, stopped for 30 mins, re-started, repeat etc all over an Army Training Area for an airsoft game without any problems Quote Link to comment Share on other sites More sharing options...
Cat_J Posted November 2, 2008 Share Posted November 2, 2008 Why are optima red tops so famous then when they only have 50Ah and 815CCA? Is its due to the gel? Quote Link to comment Share on other sites More sharing options...
Lars L Posted November 3, 2008 Share Posted November 3, 2008 It's the CCA that matters, not really Ah in this case. CCA is the power you get for a short while and that turns your starter a cold morning. An engine in good health should start almost immediately. Ah is a measure of how long time you can empty the battery like if you have an engine that is reluctaant to start and you need to engage the starter for a long time. Quote Link to comment Share on other sites More sharing options...
Kim Horsevad Posted November 3, 2008 Share Posted November 3, 2008 Well this is the battery I've ended up with: (...) Please make sure you get that battery secured properly. Batteries are very sensitive to short-circuting.... If you are lucky the battery just dies, if you are unlucky you die with the battery! Ever seen the fireball produced when you accidentially touches both terminals on a battery with a spanner? Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.