Rich Posted November 17, 2010 Author Report Share Posted November 17, 2010 Thanks for the help, will report back tomorrow...what about what Tony said and taking a reading from the alternator as well...how will I do that, positive on the alternator and negative on the battery? I'll be taking the intercooler off first to get access to the alternator and to check the belt, wiring and bushes aswell. I'm still confused as to why the battery light didn't come on though if it was an alternator problem. Quote Link to comment Share on other sites More sharing options...
randominbread Posted November 17, 2010 Report Share Posted November 17, 2010 It's easier just to measure at the battery - saves taking stuff off to get access. I wouldn't take the intercooler off until you've done the checks I've suggested first. Quote Link to comment Share on other sites More sharing options...
Rich Posted November 17, 2010 Author Report Share Posted November 17, 2010 It's easier just to measure at the battery - saves taking stuff off to get access. I wouldn't take the intercooler off until you've done the checks I've suggested first. Yeah I will mate but it's only 4 bolts, takes 2 minutes Quote Link to comment Share on other sites More sharing options...
Rich Posted November 18, 2010 Author Report Share Posted November 18, 2010 Right put the battery in and took a reading for 3 minutes, it was between 13.15 - 13.51V....started the car up and it stayed the same at idle, when revving and also with everything switched on Turned the car off and it was showing 14.30V...so looks like the alternator is buggered, can't believe that in only 4 years! I took the brushes out and one is slightly more worn than the other but I think they're still long enough? Also the ground here, I'm assuming I can put the - prong from the multimeter here and the + on the positive battery terminal although I don't think there's much point. What I don't understand is the first sign of alternator failure is the battery light coming on and my headlights had hardly dimmed the other night driving home. Although last time this happened I think the battery was pretty knackered so drained quickly. Not sure what to do now, order the one on ebay now for £55 delivered and hope it comes tomorrow or go to the motorfactors and pay twice as much...I'll ring them now for a price. Quote Link to comment Share on other sites More sharing options...
Tony Posted November 18, 2010 Report Share Posted November 18, 2010 Four years is no age ...... Quote Link to comment Share on other sites More sharing options...
Rich Posted November 18, 2010 Author Report Share Posted November 18, 2010 Four years is no age ...... Not even that really as it's 4 years in January! It was a recon one though and I got it from a MEG member so don't know it's history. Allparts have a Bosch one for £125 (+ £90 surcharge) or their own brand for £70 (+ £27 surcharge)...I think I'm gonna spend the extra £15 and get it from there now and I need a new belt as well. Even their own brand one only has a year guarantee though. Quote Link to comment Share on other sites More sharing options...
Tony Posted November 18, 2010 Report Share Posted November 18, 2010 I think that's a wise move to be honest, you ok fitting it? Quote Link to comment Share on other sites More sharing options...
Rich Posted November 18, 2010 Author Report Share Posted November 18, 2010 I think that's a wise move to be honest, you ok fitting it? Yeah should be mate, only 3 bolts, just need to get it up the road so I can jack it up to slack the belt off. I may have trouble fitting that though cos if I remember correctly the aircon belt tensioner is right next to the chassis and you need to raise the engine to undo it!! Unless I can find another way like removing one of the pulleys...shall find out in a minute Quote Link to comment Share on other sites More sharing options...
randominbread Posted November 18, 2010 Report Share Posted November 18, 2010 Right you jumped ahead a bit, I'd have liked to have done a few more checks first before removing the alternator. The alternator is still the suspect item but you haven't proved it unserviceable by fault diagnosis. You proved the battery is serviceable by 1. making sure it could be recharged, 2. ensuring its voltage remained constant over time (with no load applied) and 3. It stored and provided enough current to start the engine. Thats all the checks needed to prove battery serviceability. What I would have liked you to have done next, is to discharge the battery slightly by leaving the lights on and engine off for 1-2 minutes. check the voltage at the battery again and leave the lights on until the voltage measures 12.5 - 13v. Then start the engine and see if the alternator can recharge the battery with no other loads applied. With your battery measuring high at 13.5 - 14V it can mask the alternator problem. Quote Link to comment Share on other sites More sharing options...
randominbread Posted November 18, 2010 Report Share Posted November 18, 2010 "What I don't understand is the first sign of alternator failure is the battery light coming on and my headlights had hardly dimmed the other night driving home" If I remember correctly the battery light signifies low volts not a lack of current. An alternator should provide constant voltage and variable current. The current provided by the alternator varies depending upon the load placed on it. Your alternator seems to be providing the voltage but not the current, which is possibly why your battery light didn't come on. Would have been good for you to prove it with a few more checks. Next time don't jump the gun! Quote Link to comment Share on other sites More sharing options...
Rich Posted November 18, 2010 Author Report Share Posted November 18, 2010 Yes I may have jumped the gun abit but I really needed to get it sorted today although it didn't go to plan!! Thanks for the explanation though I will remember that in case it happens again. Got the old alternator out within minutes and went down to Allparts and got the new one plus a belt. Got back and I must've spent an hour and half trying to fit the bloody thing, got 2 bolts in but the last one wouldn't. I thought it was me but on closer inspection I was sure the actual hole wasn't lining up hence the bolt wouldn't do up. Went back down to Allparts during the rush hour and told the bloke who sold it to me. He was measuring this that and the other with regards to the hole locations and he even got the Bosch one to compare, they all seems the same. He did notice that both the new ones had a plastic part extending where the wiring goes and he thought this might be catching on something, stopping it from aligning. He said try that and if it still don't fit he'll try and do me a deal on the Bosch one. So I drive back home, again through the rush hour traffic and tried again. The part he removed doesn't come into contact with anything so it wasn't this. I'm gonna phone him in the morning and then go after work. I would go in my lunch but I only get half an hour, which isn't long enough. The Bosch one is £55 more so I'll see what deal he can do as £70 was more than I wanted to pay. If it's gonna be too much I'll only have Saturday to find one and fit it. I think the actual casing must be distorted, the hole is only a few mm out so you can't see the difference by eye. Complete and utter waste of a day though!! :angry: Where the black thing is that houses the brushes, underneath is a gold bolt. There was a plastic bracket attached to this which extended it to the right so as you can see it doesn't catch on anything. Quote Link to comment Share on other sites More sharing options...
randominbread Posted November 18, 2010 Report Share Posted November 18, 2010 Sorry to hear your having trouble fitting the new alternator. Did you compare your old one with the new ones? How much is an alternator from the stealers? What make was your old alternator? Quote Link to comment Share on other sites More sharing options...
Rich Posted November 18, 2010 Author Report Share Posted November 18, 2010 Sorry to hear your having trouble fitting the new alternator. Did you compare your old one with the new ones? How much is an alternator from the stealers? What make was your old alternator? Yes we had all 3 lined up and by eye there is no difference so used an accurate measuring tool and the holes are all in the same place but something must be amiss. It's only 3 bolts, not exactly difficult to fit, even with the first 2 slacked right off I couldn't get the 3rd one to do up. I don't use the stealers unless I have to but it will be more than the Bosch, although that is the company who make them The one I removed was a recon OEM one so a Bosch. I think it's just the manufacturing process has gone tits up with this pattern part one I got, called Drivetec. Quote Link to comment Share on other sites More sharing options...
randominbread Posted November 18, 2010 Report Share Posted November 18, 2010 My local Renault main dealer is really good on some parts and a complete rip off on others!! Right stupid question, have you tried just fitting the stubborn bolt on its own, then fitting the other 2? Is there a blob of paint on the edge of the mounting holes which may stop the bolt from aligning? Quote Link to comment Share on other sites More sharing options...
Rich Posted November 18, 2010 Author Report Share Posted November 18, 2010 My local Renault main dealer is really good on some parts and a complete rip off on others!! Right stupid question, have you tried just fitting the stubborn bolt on its own, then fitting the other 2? Is there a blob of paint on the edge of the mounting holes which may stop the bolt from aligning? All dealers are the same, I bought some new bolts for my rear arms a year or 2 ago and they wanted a tenner each...it's just a standard bolt!! Yes I tried fitting the bottom one first but it wouldn't screw in all the way. If you look in the second photo you can see the bracket that sticks out, which bolts into the side of it. It was pushing against this before I got the bolt done right up and the top one wouldn't go in Quote Link to comment Share on other sites More sharing options...
randominbread Posted November 18, 2010 Report Share Posted November 18, 2010 If it doesn't screw in all the way, then it may be that the blind hole hasn't been tapped deep enough? Quote Link to comment Share on other sites More sharing options...
Rich Posted November 18, 2010 Author Report Share Posted November 18, 2010 If it doesn't screw in all the way, then it may be that the blind hole hasn't been tapped deep enough? But the old alternator was on ok and the one before that, both OEM ones as well. I reckon it's cos this is a pattern part but the pattern obviously doesn't match! Shame I can't get the car over to WIM to see what's what on the ramp. Quote Link to comment Share on other sites More sharing options...
randominbread Posted November 18, 2010 Report Share Posted November 18, 2010 Your right about pattern parts! Could you put a few washers onto it to temporarily bodge it? Then fit the belts and go for a drive Quote Link to comment Share on other sites More sharing options...
Rich Posted November 18, 2010 Author Report Share Posted November 18, 2010 Your right about pattern parts! Could you put a few washers onto it to temporarily bodge it? Then fit the belts and go for a drive But I can't even get the last bolt to do up at all once the other 2 are tightened or even when slacked. TBH I don't like bodging jobs, I'd rather got it right first time round otherwise it means having to undo everything again. Even if I left just the 2 bolts in how am I to know whether the belt is running true, I don't want to damage an alternator I need to return or anything else for that matter. The belt also runs very close to the chassis, there is a gap of 10mm so I want one that's a perfect fit. Quote Link to comment Share on other sites More sharing options...
randominbread Posted November 18, 2010 Report Share Posted November 18, 2010 True enough mate, just thought it might be an option if you get desperate to use your car. Don't blame you for finding the correct fitment, especially when you've only got a 10mm gap between the belt and an obstruction. Quote Link to comment Share on other sites More sharing options...
Rich Posted November 19, 2010 Author Report Share Posted November 19, 2010 Just back from Allparts and showed the guy my photos etc...accepted there must be something wrong, I weren't going back and forwards from there for the good of my health! He said he could do the Bosch one for an extra £17, which I accepted, that's £40 off what it should've been. It's also an OEM one as it's got Motorcraft stamped on it! Plus whenever I've been to Fords for something and it's not in stock they send me to Allparts as that's where they get it from! I'll be fitting it later and hopefully it will all go ok, better had no I'm £87 lighter. I'll leave the belt until another time, plus I need to figure out how I'm going to change that anyway. Quote Link to comment Share on other sites More sharing options...
Rich Posted November 19, 2010 Author Report Share Posted November 19, 2010 Well it bolted on ok so I put everything back together but got a problem. The battery was reading 13.5v but was creeping up over 3 minutes, it reached 15.5v. Starting the car caused it to jump to 16.5v so the alternator is working and under load it creeped up to 18.5v and was still going! What does this mean then? Quote Link to comment Share on other sites More sharing options...
randominbread Posted November 19, 2010 Report Share Posted November 19, 2010 It's reading a bit high, but its to be expected to jump up in voltage when you load the alternator though. Start you car again but leave everything off, let it settle for a few minuets then check the voltage again. Quote Link to comment Share on other sites More sharing options...
Rich Posted November 19, 2010 Author Report Share Posted November 19, 2010 Yep I thought that might be the case...over 3 minutes it's 12.95v, with the engine on it's 14.5v and when it's loaded it increases slightly. I'll check again in the morning. I've got a photo to upload when I get on the PC about changing the belt and I think I need to change one of the connectors for the alternator aswell cos the plastic clip snapped so it doesn't clip in place. Well now that's sorted I think it's time to get some new brakes, the pads are pretty low now and they don't feel as sharp. Going for mintex boxset, can't go wrong with those. Quote Link to comment Share on other sites More sharing options...
randominbread Posted November 19, 2010 Report Share Posted November 19, 2010 The readings you've just taken are really good, you couldn't ask for better really. Tomorrow, just for fun, take a measurement directly from the +ve terminal of the alternator. Leave the -ve lead of the multimeter on the -ve battery terminal. You shouldn't see much difference from when you measured across the battery. This will prove to you that you don't always have to take a reading from the suspected faulty component, thus saving you from taking off the intercooler or any other stuff. Always do the simplest voltage checks possible. Why not study up on basic DC electricity, You've already got all the kit you need - the multimeter!! Quote Link to comment Share on other sites More sharing options...
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