Dave SL77 Posted October 18, 2009 Share Posted October 18, 2009 I will get in touch with Ed at powervamp tomorrow, but meanwhile, can anyone offer feedback to my query? I replaced my old battery that I "thought" was on its way out with a lovely little PVR25 and new battery box, and the car fails to start unless its "just off the conditioner" sometimes only when jump connected to the old battery that I removed. It fires no problem after a run since its charging via the alternator no problem (SPA digi volt gauge), but if its left to go cold like all day at work then it wont start unless jump started by another car. Its got an FIA master switch so its fully cut off. I since day one discounted the new battery as the problem, and since replaced various items including the starter motor, but its still no better. So, could it be a duff battery, or is it simply not a man enough battery for a 1.9k Scholar? and I have bought the wrong size? Can I "test" one of these batterys or should I send it back to Powervamp? Edited by - Dave SL77 on 31 Oct 2009 17:18:08 Edited by - Dave SL77 on 1 Nov 2009 10:56:43 Link to comment Share on other sites More sharing options...
pjp Posted October 18, 2009 Share Posted October 18, 2009 I have just changed my old battery to a PRV25 and I am having similar problems. Will not start without a jump when cold. Poor hot starting. Never had this problem with old Powervamp battery. Boycie Link to comment Share on other sites More sharing options...
henry21p Posted October 18, 2009 Share Posted October 18, 2009 Check the power to the large wire on the starter. I thought I had a battery problem, but it was this wire that went from alternator to starter that was the issue. Changed it so the starter gets a kick direct from battery when engaged and everything's been fine since. Link to comment Share on other sites More sharing options...
Carlos Prangdango Posted October 18, 2009 Share Posted October 18, 2009 It's not much use towards solving your problem, but i have just changed to a PRV25 and it starts like never before, straight off the button. Link to comment Share on other sites More sharing options...
millsn Posted October 18, 2009 Share Posted October 18, 2009 Check your battery earth leads and your power leads. I've seen them almost fully corroded through just behind the insulation Link to comment Share on other sites More sharing options...
Myles Posted October 19, 2009 Share Posted October 19, 2009 One thing to ask Ed is what the alternator charging voltage should be... I'm sure I remember him telling me that it should *ideally* be higher than for a normal battery. 🙆🏻 🙆🏻 🙆🏻 🙆🏻 🙆🏻 Alcester Racing 7s Ecosse™ 🙆🏻 🙆🏻 🙆🏻 🙆🏻 🙆🏻 Alcester-Racing-Sevens.com Link to comment Share on other sites More sharing options...
Paul Deslandes Posted October 19, 2009 Share Posted October 19, 2009 put a volt meter across the battery directly onto the terminal posts when you're cranking the engine. If the voltage stays up but it won't start, then the battery's ok and the problem is elsewhere. If the voltage drops too far then its the battery. Link to comment Share on other sites More sharing options...
Dave SL77 Posted October 19, 2009 Author Share Posted October 19, 2009 Thanks for the feedback guys. Ok, so ordered new battery cabling to replace it all, and havent yet spoken to Powervamp since I have had too much feedback suggesting other things. (Hopefully will fit the new cabling this week) So I had it on the conditioner all day, and because its now starting well I removed the HT lead to make sure it wouldnt fire. At rest - 12.42V or thereabouts Cranking, measured across the battery - 10.6 -10.7V Cranking, measured across the starter motor "post" - 9.6V Go easy on me as I aint no electrician, but is the 1.00V difference normal or likely the cause. Bear in mind the above readings were fresh off the conditioner and the car was starting on the button beautifully. When its up and running the spa gauge is reading 14.00 V or thereabouts. Edited by - Dave SL77 on 19 Oct 2009 19:00:29 Link to comment Share on other sites More sharing options...
Myles Posted October 20, 2009 Share Posted October 20, 2009 Again, from memory, 12.4V across a 'freshly-charged' Powervamp is not good. ISTR that 12.86V is regarded as approximately charged. Your conditioner probably is just that - and is no use for actually replenishing a discharged battery. The bad news is that the deeper and more frequently you discharge a red-top type of battery, the quicker you will kill it... If your alternator hasn't been feeding enough jolts (not forgetting the preferred higher charging voltage if I recall that correctly), your battery may well be toast. 🙆🏻 🙆🏻 🙆🏻 🙆🏻 🙆🏻 Alcester Racing 7s Ecosse™ 🙆🏻 🙆🏻 🙆🏻 🙆🏻 🙆🏻 Alcester-Racing-Sevens.com Link to comment Share on other sites More sharing options...
Dave SL77 Posted October 20, 2009 Author Share Posted October 20, 2009 Thanks Myles, The thing is the problem has been like this since day one with the battery, so I fear that I have not toasted it, its simply been duff from day one, if what you say is correct ref the volatges. Any comment on the variation between the voltages across battery vs across the starter motor? If I am being honest, the battery fresh off the conditioner, was reading 12.75 ish Volts but I did a couple of turn overs that started the car (always does it when you dont want it to) and then I disconnected the HT lead and took the readings. Can anyone tell me what type of charger you are supposed to use on one of these batterys? I was told only the conditioner type should be used and not a "normal" charger. So I spent £50 at the time for one from Powervamp to ensure it "was the right one for the job". Am I being told thats wrong too now? Great. Link to comment Share on other sites More sharing options...
peterg Posted October 20, 2009 Share Posted October 20, 2009 no, if Powervamp sold you one that should be fine Link to comment Share on other sites More sharing options...
Dave SL77 Posted October 20, 2009 Author Share Posted October 20, 2009 thanks peter! Still no-one able to comment on the Voltage variation? Link to comment Share on other sites More sharing options...
jackb_ms Posted October 20, 2009 Share Posted October 20, 2009 if you read 9.6V at the starter post check the cables back to battery and earth Jack Emily, The Very Yellow 21 Link to comment Share on other sites More sharing options...
Dave the Dentist Posted October 20, 2009 Share Posted October 20, 2009 I recently had a hot starting problem with my K series, which was finally traced to the starter being misaligned against the ring gear on the flywheel, when hot it would jam. I think it was a misalignment of the starter seating onto the bell housing. Even a new Brise starter had to be tweeked to line it all up correctly. A BiG to James Whiting for sorting this one. D Link to comment Share on other sites More sharing options...
MartinP Posted October 20, 2009 Share Posted October 20, 2009 I don't know any specifics regarding the Powervamp battery so I'll just have to resort to basics. It strikes me that there are two possibilites here, either you have a duff (even though it's new) battery or it's marginal on being big enough for the job. To test a battery needs a drop tester. Basically this applies a heavy current load to the battery and measures the battery terminal voltage at the same time. The test should be done on a fully charged battery and the voltage should hold up i.e. the test measures the ability of the battery to supply load. The measuring voltmeter is usually 'calibrated' with red / yellow/ and green sections to indicate fail / not too good / and pass. Most tyre and battery places will have one and will do you a test on spec. I think from what you say however (regarding the voltage you measured at the battery during cranking) that I would prefer the idea that your battery is close to the limit of being 'big enough' to do the job and that, combined with perhaps not being fully charged and maybe a slightly too high voltage drop along the cabling, is enough to tip it over the edge. One volt strikes me as being a little high to drop along the connections but I've never measured it so can't be positive. Perhaps this is part of the problem and you have a poor termination or poor condition cable. For a standard lead acid battery, 2.1 volts per cell is fully charged i.e. 12.6 volts. If that is the case for the Powervamp then you are not quite charged at 12.42 V but again not far off although ok at 12.75 ish that you mention. I can't comment specifically if the Powervamp battery is any different and if the 12.86 V figure is correct then you are slightly low. The 14 volts you measure when running is about right although perhaps a little low but the proof of this is that you can start up ok after a period of running. This is pointing to the battery being a little too small for the job and only when it is absolutely fully charged will it be ok. That may be being made a little worse if you have poor condition cable or connections so that would be the first thing to check. Bear in mind though that with the previous battery it was ok so is probably only a contributing factor. A battery will have a specified cranking current capability and it is this which is critical in matching battery to starting duty. If that capability is too small or doesn't have enough margin in hand then you will have problems if there is anything else working against you (not fully charged or poor connection / cable). Only problem is I don't know what the cranking current of your starter motor is to be able to compare so I suggest you approach it another way. Find out the specified cranking current of both the old and the new batteries and see how they compare. If the Powervamp is significantly lower then that would be my starting point. If that isn't easy to find then fully charge your old battery and fit it to the car. Retry your cranking tests and compare the voltages. Ideally you want to compare the current in each case which I don't suppose you can measure so try a different approach. Compare the volts drop (difference between battery volts and terminal volts but you'll need to measure it accurately) between the two tests and assuming the connecting cables are a constant resistance then that is as good as comparing current. If there is a higher volts drop with the old battery then it has been supplying a higher cranking current. To do this effectively though you should compare a successful start with the old battery against a failed start with the new and this will give you an idea of where your problem lies. To help you work out the results for yourself try thinking along these lines. The starter motor will draw sufficient current to turn the engine over against the mechanical load and it will do this repeatedly (providing the engine's resistance to turning is the same). If there is a limit somewhere else in the circuit however the motor won't be able to draw sufficient current for its needs and the torque will be reduced as a result. With the old battery fully charged we presume there is no constraint from the supply side and the motor then provides the limit. If the new battery is however struggling because it is a bit small or not quite fully charged then it will provide the limit and the motor will suffer reduced torque. Increased resistance in the circuit (cable or connections) will create a 'resistance' to current flow and if this is great enough could also be a factor. You should however be ok providing it isn't too high a resistance or the battery has enough in hand to overcome it. Hope that helps, apologies for the length of this bumf, I'm off for a lie down in a darkened room Link to comment Share on other sites More sharing options...
Grubbster Posted October 20, 2009 Share Posted October 20, 2009 Speak to Ed, it sounds very much like you have a bad battery. I have the PVR25 and no problems starting, the engine cranks quite a bit faster than it ever did on the Banner that I had from new. So if you haven't changed anything else then I suspect the battery is the problem. These batteries hold their charge very well as long as there is no small load left on (e.g. like the imobiliser) so in theory you shouldn't have a problem due to leaving it a while between use. From Ed - Don’t be put off by the size, with 680 cranking amps available the battery will turn over engines in excess of 3ltr. Link to comment Share on other sites More sharing options...
Dave SL77 Posted October 20, 2009 Author Share Posted October 20, 2009 Cheers for the comprehensive reply Martin! I have ordered new cabling for the power, I will fit it sunday, and if its no better, will speak to Ed at Powervamp for further advice, and take it from there. Link to comment Share on other sites More sharing options...
Dave SL77 Posted October 31, 2009 Author Share Posted October 31, 2009 Since so many threads get left "open", I thought I would clarify that there was nothing wrong with my battery. The new power cabling was fitted las sunday and makes all the difference and the car is starting no problem, and was left off the conditioner all week and still starts the car no problem. New axial Starter, new cables, check up and updated firmware on the Emerald. Maybe collectively made it better, but I am now a happy bunny. 😬 New CPS/IACV/Coolant and Air Temp sensors cost money and were red herrings as I tried to narrow down the problems but its all about learning the car I suppose. Cheers David Link to comment Share on other sites More sharing options...
Myles Posted October 31, 2009 Share Posted October 31, 2009 You can go back and edit the title via the first post if you want... 🙆🏻 🙆🏻 🙆🏻 🙆🏻 🙆🏻 Alcester Racing 7s Ecosse™ 🙆🏻 🙆🏻 🙆🏻 🙆🏻 🙆🏻 Alcester-Racing-Sevens.com Link to comment Share on other sites More sharing options...
Dave SL77 Posted October 31, 2009 Author Share Posted October 31, 2009 So I can, changed now to something that might help when folk are searching archives. Link to comment Share on other sites More sharing options...
geko Posted October 31, 2009 Share Posted October 31, 2009 Hi, the PVR25 and the Odyssey extrem racing 25 are quite the same batteries. pur lead, thin plate, AGM... From the odyssey manual: 100% charge = 12.84V or higher 75% charge = 12.50V 50% charge = 12.18V 25% charge = 11.88V measure: 8h after disconnection (no power consumtion!!) Best regards Gerhard Caterham CSR 200 MAZDA MX-5, NB, 1840ccm Link to comment Share on other sites More sharing options...
Bob_Rich Posted October 31, 2009 Share Posted October 31, 2009 when cranking and the voltage is checked at 9.6V is this across the motor? i.e measure from the motor power terminal to the motor frame. This will then include the voltage drop across the earth return to the battery. Depending upon the earthing the actual voltage that the ECU sees may be low enough to prevent getting an adequate timed or amplitude sparking voltage to the plugs. Possible trick would be to use you spare battery to power up the starter motor only so that the volts do not fall on the rest of the car electrics. If it starts OK then it may be the volts drop is going just a tad too low Hope this helps Bob Link to comment Share on other sites More sharing options...
Dave SL77 Posted November 1, 2009 Author Share Posted November 1, 2009 Cheers for the readings geko, they are not far off the readings I now get. Bob, cheers for your thoughts, but I was only bringing the post alive to explain the problem was fixed. Thanks David. Link to comment Share on other sites More sharing options...
Roger Ford Posted November 23, 2009 Share Posted November 23, 2009 Where did you get the axial starter motor, Dave? Is this the type CC used to sell, or an aftermarket one? Link to comment Share on other sites More sharing options...
Steve T Posted November 23, 2009 Share Posted November 23, 2009 Funny enough I have an issue with my new PVR25. 4 years on the Banner and not a single K click. Now had about 6 K click episodes in not many more starts from cold on my new PVR25. Now, I am a competant electronics engineer and as such looked into this carefully. I took the opportunity to get rid of the supplied CC battery cables and made up some new ones with 25mm sq cable and proper crimps (cimped with an £800 hydraulic crimp tool just for the measure) and soldered with an RF soldering iron (£1,000 worth) and heatshrinked etc. Just to eliminate any voltage drop issues. When fully charged on conditioner for 2 days my no load volts across battery are 12.51V, when cranking (firing disabled) i get 9.1V across starter (big terminal and solenoid), so i checked across battery and I get 9.3V so no issues with the cables BUT I would have expected more volts from the battery as it is almost new. My Banner, before it died after 4 years, used to drop to 10.2V on cranking when fully charged, like others, I replaced with a PVR25 as a good upgrade - now I am not so sure, maybe I have a duff one ? Steve Now with DVA Power! 191bhp and 150.9 lbft torque. My Pictures Link to comment Share on other sites More sharing options...
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