sotal Posted November 24, 2007 Author Share Posted November 24, 2007 Well I go tup early this morning in the bitter cold, to get a few readings before attempting to start, I never got chance to take the battery off so my idea was to try and start the disco with the battery that's on it if that failed I was going to use the old one which had been on charge. Anyway, I took a reading of the Voltage before I did anything - it was at 12.52 volts, I then turned the ignition on which activated the glow plugs and the fuel injection pump - with these two on the voltage dropped to 11 volts, when the light went out but I presume the glow plugs remained on, it stayed at 11 volts and I turned the key to start it up, the voltage dropped down to 9 volts and it fired straight up! Once running the voltage went to 13.56 volts, I left it running on the drive and went back about 5 mins later, it was then at 14 volts, I switched off the disco and took a final reading which was 13.5 volts. Does that all sound OK? - I've got no idea why it started today - it was bloody cold so following the normal pattern it should have failed! Any suggestions? I'll try again in the morning and see if I get anything different Cheers Quote Link to comment Share on other sites More sharing options...
pinny Posted November 24, 2007 Share Posted November 24, 2007 read through your thread and i had the same prob last winter fitted a battery the biggest that would fit in the tray and most amp new alternator and when we got a frosty morning turned over rearly slow cleaned all terminals etc fitted a new starter motor and no probs at work last week had a similar prob with a jcb which is only six months old cold morning no go slow at turning over fitted a new motor no probs o would say its starter motor as you have covered everything else chris Quote Link to comment Share on other sites More sharing options...
sotal Posted November 26, 2007 Author Share Posted November 26, 2007 Well it's started fine every time since, probably a bit warmer though. What Voltage is everyone else's battery at - at rest before you try starting and what does it drop to? Cheers Quote Link to comment Share on other sites More sharing options...
BogMonster Posted November 26, 2007 Share Posted November 26, 2007 Should be about 12.6 to 12.8 volts (digital multimeters vary in their accuracy!) for a well charged battery. If it's less than that then there is a problem. Quote Link to comment Share on other sites More sharing options...
Les Henson Posted November 26, 2007 Share Posted November 26, 2007 The test you are doing is referred-to as a 'drop test'. A faulty starter motor will 'suck the guts' out of a battery in an attempt to start the engine. I always thought that a drop test below 9-volts indicated a dodgy battery? Les. Quote Link to comment Share on other sites More sharing options...
sotal Posted November 26, 2007 Author Share Posted November 26, 2007 Hi Les, thanks for the response, when you say a faulty starter motor would suck the guts out of a battery what kind of voltage would you expect? The battery shouldn't be faulty as that's the brand new one. My only other thought at the moment is the alarm. I've checked to see if there is any current drain on the system, but only when it's just sitting there. I've never tried with the alarm on, I'll try sticking a brick on the bonnet sensor and see if I can set the alarm with the multimeter in parallel to see if there is much of a drain Quote Link to comment Share on other sites More sharing options...
sotal Posted November 26, 2007 Author Share Posted November 26, 2007 I've just had a quick search on the web, and my figures seem OK The Rest Voltage should be 12.6 volts (mine was 12.52) anything above 12.4 is acceptable The cranking voltage should be 9.6 volts at 20 degrees C (mines was 9 volts at about 2 degrees C) anything between 9 and 10 volts is acceptable. The only thing is when I did my tests the disco started! I guess I need a set of figures when it's cold enough not to start!? Quote Link to comment Share on other sites More sharing options...
white90 Posted November 26, 2007 Share Posted November 26, 2007 you are spending far more time effort than is required Go and get a new starter motor my 300TDI did the same as you describe the dealer replaced the battery as it was cheap then the glowplugs again cheap earth strap(cheap) finally a new starter it has been fine for the following six years Quote Link to comment Share on other sites More sharing options...
BogMonster Posted November 26, 2007 Share Posted November 26, 2007 It sounds very much like the starter motor to me. Even if it isn't, a 12 year old diesel starter motor will hardly be in the first flush of youth so a replacement will not be wasted. Quote Link to comment Share on other sites More sharing options...
sotal Posted December 11, 2007 Author Share Posted December 11, 2007 Just a quick update - the disco hasn't failed to start for the last 18 days, but this morning was very frosty and cold and it didn't quite go. I couldn't find the multimeter to test the levels, and I didn't have time to swap the battery for a known charged one, I tried connected both jump leads to the negative terminal and then the other ends to different places on the block and it made no difference - so I think that rules out bad earth. Reluctantly I must admit that Les and Bog Monster and everyone else who reckon it's the starter motor might be right. So I've got a few questions along those lines: I've read through Les' Guide on how to Replace the Starter motor and that all looks doable. Les mentions that one type of starter motor is better than the others, is their any type which is the best to go for? How much should I expect to pay for a starter motor? Am I doing any damage if I just leave it and keep jump starting the vehicle? - I only ask because I know I'm too busy to do the job until the middle of Jan at the earliest probably more like Feb. As the second battery always works - Is it worth fitting the 2nd battery somewhere and having a switch to knock it on for startup? - Is there any where it can easily fit? My local spares place only does a "Bosch Type Starter Motor" which has a nasty little "Britpart" logo next to it and that costs £99.87 which I thought was quite expensive Quote Link to comment Share on other sites More sharing options...
Les Henson Posted December 11, 2007 Share Posted December 11, 2007 'Bosche type' means nothing at all - they might as well say 'metal type' or 'starter motor type'. I don't know if continually jump starting would cause the related wiring to get too hot - all those amps ain't good O would have thought, although some people have whopping-great batteries on their trucks as standard. There are three makes of starter (they are interchangeable) Prestolite, Valeo, and Bosch. I don't rate Prestolite as very good, although one or two on here have had no problems with them. Les. Quote Link to comment Share on other sites More sharing options...
sotal Posted December 11, 2007 Author Share Posted December 11, 2007 Thanks Les, any idea what price I should expect for a starter motor? Quote Link to comment Share on other sites More sharing options...
BogMonster Posted December 11, 2007 Share Posted December 11, 2007 Reluctantly I must admit that Les and Bog Monster and everyone else who reckon it's the starter motor might be right. Hallelujah! Suggest you tot up the amount of time you will waste between now and the end of Feb jump starting your vehicle and you will probably find it takes a lot less time to change the starter motor... Quote Link to comment Share on other sites More sharing options...
sotal Posted December 11, 2007 Author Share Posted December 11, 2007 ok ok "I told you so" etc etc I've got 5 minutes spare every morning, but I haven't got a couple of hours spare, so it'll have to wait, I'll probably get the starter motor though so it's ready - then it'll make me do it as well, I've got a pile of bits waiting to go on as it is Quote Link to comment Share on other sites More sharing options...
Ivan Posted December 11, 2007 Share Posted December 11, 2007 I recently paid £120 for my Bosch starter motor. Had 3 prestolites fitted and they all packed up inside 3 months. At least my supplier fitted the last one for free (others were fitted by my local mechanic). As Les said buy Bosch or Valeo the prestolites are cr*p. Rgds Ivan Quote Link to comment Share on other sites More sharing options...
Happyoldgit Posted December 11, 2007 Share Posted December 11, 2007 ok ok "I told you so" etc etc I've got 5 minutes spare every morning, but I haven't got a couple of hours spare, so it'll have to wait, I'll probably get the starter motor though so it's ready - then it'll make me do it as well, I've got a pile of bits waiting to go on as it is Hmmmm - who's saying you have to do it in the morning? I know of very few people apart from leaders of nations and the pope who do not have an hour or two to spare a week. Just spend a few quid, get a &%^*"@ starter and get it fitted or get someone to fit it for you. Job done. Sorted. Finished. No more stress watching the weather forecast and praying for it to stay mild. Life can move on. ....and breathe. Quote Link to comment Share on other sites More sharing options...
Sean Posted December 11, 2007 Share Posted December 11, 2007 I live in Staffs, where are all these speed bumps you keep on about ? Quote Link to comment Share on other sites More sharing options...
sotal Posted December 11, 2007 Author Share Posted December 11, 2007 I live in Staffs, where are all these speed bumps you keep on about ? stoke-on-trent Quote Link to comment Share on other sites More sharing options...
sotal Posted December 12, 2007 Author Share Posted December 12, 2007 Now the strange thing is it started this morning and it's bloody cold! There's frost everywhere car needed de-icing etc but it started straight away, it's the first time it's ever started on such a cold day. Quote Link to comment Share on other sites More sharing options...
white90 Posted December 12, 2007 Share Posted December 12, 2007 Take the starter motor back and get a refund Quote Link to comment Share on other sites More sharing options...
sotal Posted December 12, 2007 Author Share Posted December 12, 2007 I'll take that as sarcasm - I do believe you all that the starter motor is the cause and when I get the time I will get it sorted Quote Link to comment Share on other sites More sharing options...
Les Henson Posted December 12, 2007 Share Posted December 12, 2007 Matbe it's not the starter motor after all.................. Les. Quote Link to comment Share on other sites More sharing options...
sotal Posted December 12, 2007 Author Share Posted December 12, 2007 Are you being serious there?? Quote Link to comment Share on other sites More sharing options...
Les Henson Posted December 12, 2007 Share Posted December 12, 2007 Not bluddy likely Les. Quote Link to comment Share on other sites More sharing options...
sotal Posted December 13, 2007 Author Share Posted December 13, 2007 Just to add to my personal daily diary.... It wouldn't go this morning, but I was in a rush so I jumped in the Series which has never let me down, and that did the same The difference with the series was that the starter would turn once fast then go really slow - wheras the disco keeps turning at an OK speed - enough to normally start it but no fuel comes out of the injection pump, adding the second battery speeds the starter up a little and fuel flows. With that last bit about no fuel but an ok speed from the starter - are you positive it's the starter??? Ok ok I believe you Quote Link to comment Share on other sites More sharing options...
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