EPP Posted February 1, 2009 Share Posted February 1, 2009 I'm making progress with my XJ600. Brakes and exhaust are done, and I'm ready to get back on the road... but it was never going to be that easy was it? The engine just turns over until the battery dies, doesn't seem to catch at all. However, if I jump it from a car battery (i know some people would advise against this) the engine will turn over repeatedly until it just begins to catch, and eventually it will splutter into life. Once going, it warms up fine and seems to run well, then restarts immediately from the bike battery after being shut off. So, I'm wondering what this might be all about. Could it be that fuel is taking ages to get the engine? Could the carbs have got gummed up while the bike has been laid up (but presumably this would mean it wouldn't start at all)? Could it be something electrical? The thing I find strange is that it will finally get going and run well after that. Any suggestions? Link to comment Share on other sites More sharing options...
shed hermit Posted February 1, 2009 Share Posted February 1, 2009 i would look at the carbs if the bike has been laid up for a while with the petrol in it as the petrol forms crystals after a while, also look at the condition of the air filter as if the air cant get in it wont carry the fuel to the cylinders. Link to comment Share on other sites More sharing options...
Moderator Airhead Posted February 1, 2009 Moderator Share Posted February 1, 2009 It has to be the battery then doesn't it? Link to comment Share on other sites More sharing options...
EPP Posted February 1, 2009 Author Share Posted February 1, 2009 It has to be the battery then doesn't it? But even with a car battery it takes a looooong time before anything starts to happen (about a minute or two of repeatedly turning the engine over). I'll have a look at the air filter now. I also need a plug socket so i can get the plugs out to check them. Will also check the ignition components if I can, but the manual suggests building a little tool to help with this, and I might not have the time. Could it be a problem with the carbs if the engine eventually starts going and then runs well? Link to comment Share on other sites More sharing options...
shed hermit Posted February 1, 2009 Share Posted February 1, 2009 dont hold the starter on for too long, 10-15 seconds at a time and give it a chance too cool a bit or you could burn it out, starters take a lot of power hence the heavy wires. clean out the carbs anyway and check the float heights, it wont do any harm and gives peace of mind. also look at the fuel flow to the carbs as there might be a blockage/kinked pipe. hopefully its something simple. good luck. Link to comment Share on other sites More sharing options...
Moderator Airhead Posted February 1, 2009 Moderator Share Posted February 1, 2009 But even with a car battery it takes a looooong time before anything starts to happen (about a minute or two of repeatedly turning the engine over). I'll have a look at the air filter now. I also need a plug socket so i can get the plugs out to check them. Will also check the ignition components if I can, but the manual suggests building a little tool to help with this, and I might not have the time. Could it be a problem with the carbs if the engine eventually starts going and then runs well? I think you should do a compression test, could be time for a rebore, or new rings, a compression test will tell> You could try a squirt of oil in each plug hole, this will help the rings get a good seal, if it starts quick it will confirm the above Link to comment Share on other sites More sharing options...
YPVS TONE Posted February 1, 2009 Share Posted February 1, 2009 If your having trouble starting after not being started for a week or two try turning the petrol tap to the prime position to fill the carbs for a few seconds then back to the on position this saves the battery while the carbs fill up. I have this on my RD350 powervalve if left for a few weeks the fuel seems to evaporate from the carbs so now i turn to the prime position for a few seconds then back to the on poition and it usually starts second or third kick. Tony. Link to comment Share on other sites More sharing options...
EPP Posted February 1, 2009 Author Share Posted February 1, 2009 Checked air filter - a little grubby but nothing that would obstruct air flow. Can't get the plugs out right now - need an 18mm socket (will try and buy one today). I tried draining one of the float bowls, and fuel flowed freely out of it so I think fuel is reaching the carbs. I can also see the fuel in the line coming from the tap if i shine a torch down it. I think I might take the carbs off and give them a clean anyway. Any advice on how to do this? The manual outlines how to perform a complete strip down and rebuild (with rebuild kit) but I was hoping I might be able to avoid this. I may be shopwing my inexperience, but can I get away with spraying a few key parts with carb cleaner? Should I just be using engine oil if decide to squirt a little into the plug holes? Thanks for the advice RE not overworking the starter motor - I don't want to create more trouble! Link to comment Share on other sites More sharing options...
Moderator Airhead Posted February 1, 2009 Moderator Share Posted February 1, 2009 Should I just be using engine oil if decide to squirt a little into the plug holes? Yes. Link to comment Share on other sites More sharing options...
EPP Posted February 1, 2009 Author Share Posted February 1, 2009 Just checked the ignition coils - primary and secondary resistance - and the cap resistance. Here's what the manual says: Primary resistance was 2.6 for both coils, which is correct for a pre 1989 xj600. Mine is a 1990... Secondary resistance was around 12k for both coils. No problem there. The cap resistances were approx (from left to right) 9.6k, infinite, 12.2k, 9k. So, one definitely faulty cap, and one with higher than specified resistance. I suppose I need to get the caps replaced. Given that the primary resistance on the coils was the same, I'm guessing they're not faulty and I possibly have the older style. Really want to get the plugs out to have a look. Link to comment Share on other sites More sharing options...
Moderator Airhead Posted February 1, 2009 Moderator Share Posted February 1, 2009 Just checked the ignition coils - primary and secondary resistance - and the cap resistance. Here's what the manual says: Primary resistance was 2.6 for both coils, which is correct for a pre 1989 xj600. Mine is a 1990... Secondary resistance was around 12k for both coils. No problem there. The cap resistances were approx (from left to right) 9.6k, infinite, 12.2k, 9k. So, one definitely faulty cap, and one with higher than specified resistance. I suppose I need to get the caps replaced. Given that the primary resistance on the coils was the same, I'm guessing they're not faulty and I possibly have the older style. Really want to get the plugs out to have a look. Hmm your 1990 bike might have been made in 89 or earlier, whats the chance that someone changed both coils for the wrong ones, I would think it unlikely myself, maybe the engine number will tell the tale somehow, It does look like you have the older style but dont assume this isnt correct for your bike, possibly it just wasnt sold until 1990. As for the plug caps, good find there and replace the out of spec ones. Link to comment Share on other sites More sharing options...
steve 46 Posted February 1, 2009 Share Posted February 1, 2009 sound like the battery to me. i have a simily problem with mine. dont strart it for a few days and she refuses to sytart until battery stops. i put the charger on it for a couple of hours and it bursts into life. hope this helps Link to comment Share on other sites More sharing options...
hobbo Posted February 1, 2009 Share Posted February 1, 2009 hi i have a fz 600 the same sort of engine some small differences, i to have add 12v power pack to get the bike running i have replaced the coils plugs leads and plugs new battery checked the charge from the generator cleaned cabs checked resistence of coils etc, i have used easy start this does help but not ideal, does the battery show any input when running as mine goes flat from a full charge i think i have tracked it down to the rectifier regulator being at fault , and use digital oms tester . hope this helps dave Link to comment Share on other sites More sharing options...
EPP Posted February 1, 2009 Author Share Posted February 1, 2009 hi i have a fz 600 the same sort of engine some small differences, i to have add 12v power pack to get the bike running i have replaced the coils plugs leads and plugs new battery checked the charge from the generator cleaned cabs checked resistence of coils etc, i have used easy start this does help but not ideal, does the battery show any input when running as mine goes flat from a full charge i think i have tracked it down to the rectifier regulator being at fault , and use digital oms tester . hope this helps dave Hi Dave, I've already replaced my reg/rec after having the same problem as you - the bike would run for a day or two, then I'd try and start it and lit would be dead. Seemed to sort it right out (a good 14+v across the battery when running), but on my maiden test ride following the repair, I stopped off at my mates house and the bike was nicked! I presume it was ragged about the local park, as it was picked up by the police a few streets away. Anyway, I've been tinkering with it since (that was last November), and the problem is that I don't know exactly what the bike went through! It doesn't start properly even from a car battery, so it can't just be that unfortunately. I'm just having to deal with each new problem as it arises - it's only this weekend that I've got the bike to the point where I can work on getting the engine running again. I only passed my test last November, and this is my first bike, so it's been a baptism of fire! I'd always planned to learn how to maintain it myself, but not as quickly as this... Link to comment Share on other sites More sharing options...
EPP Posted February 4, 2009 Author Share Posted February 4, 2009 Hi all. An update... The problem ended up being with the choke. Whatever those pesky thieves did, they interfered with the choke mechanism so that it wasn't doing doing its job. I was just cranking the engine without the extra fuel getting to the carbs - no wonder it would take ages to catch but finally get running. I thought it might have been a fuel problem, but that didn't seem to explain why it would finally get running and stay running. Sorted the choke, now it seems to start pretty well. Time will tell if it's going to be reliable though. At least I've been out for a short ride to try and bed the new pads in. I think they'll need a few more miles though. The only strange thing is that once the engine is running with the choke on, the revs gradually die away. It requires the odd blip of the throttle until things have warmed up. It wasn't like this before the theft - I could just leave the bike to warm up and push in the choke after a few minutes. It's no big deal, but if anyone knows of anything I should be adjusting then let me know! I got a plug socket through the post, so I'm going to check the plugs for peace of mind. I reckon they'll be okay though. Ewan Link to comment Share on other sites More sharing options...
EPP Posted February 8, 2009 Author Share Posted February 8, 2009 If only things were simple... The engine just would idle properly, so I ended up taking the carbs off and taking them apart. There was quite a lot of crud, and some water, in the float bowls, so everything got a good clean with carb cleaner including all the jets and passages. Reinstalled it and managed to get it started, but now it idles even worse than before! It keeps stalling, and the revs pick up really slowly. Maybe there's still some carb cleaner blocking the pilot air passage or some other passage... I've also taken the plugs out and found they are black and sooty, suggesting the engine had been running rich. That would make sense given that the previous owner found it started fine without choke. How do I adjust the fuel/air mixture? I didn't remove or adjust the pilot screw as it advises against it in the manual, and I assume this only affects the idle mixture. Could this lead to the black plugs, or are they to do with the mixture at high revs? How would I adjust this? I've tried to search for these answers but didn't come up with anything. Cheers, Ewan Link to comment Share on other sites More sharing options...
T1A50 London Posted February 8, 2009 Share Posted February 8, 2009 Hi Sorry i can't help much with the problems your having as I've only had a bike for a month. I know that you sprayed your exhaust pipes, it would be fantastic to have a look at some pictures of the finished job. Cheers Link to comment Share on other sites More sharing options...
EPP Posted February 8, 2009 Author Share Posted February 8, 2009 Hi Sorry i can't help much with the problems your having as I've only had a bike for a month. I know that you sprayed your exhaust pipes, it would be fantastic to have a look at some pictures of the finished job. Cheers I'll see what I can do. It's just a matt black finish - not that pretty (but not ugly either) but cheaper than replacement! Should keep me going for a while. Link to comment Share on other sites More sharing options...
EPP Posted February 9, 2009 Author Share Posted February 9, 2009 I replaced the plugs and first signs are good. Took a while to start (probably still working fuel through the system following removal/reinstallation of the carbs) but once fired up it seemed to idle well and was very responsive on the throttle. Not had a chance to ride it yet. Also replaced the air filter - it was pretty mucky, and this might have been causing the engine to run rich. I didn't check the air filter after I bought the bike last November, so I've no idea if had been like this for ages or was fouled up while it was stolen. Assuming the bike continues to run, I'm going to keep an eye on the plugs after each ride. If they get sooty, I'll know it's to do with the jetting in the carbs - probably the secondary (needle) jet... I'm also thinking of putting some redex, or similar, through the engine just to give the carbs a final clean and hopefully remove any crud from the combustion chamber. Anyone got any thoughts on this? Is it a gimmick? A waste of time...? Cheers all, hopefully recording the steps i've taken will be helpful to someone else at some point! Ewan Link to comment Share on other sites More sharing options...
Matty Towel Posted February 12, 2009 Share Posted February 12, 2009 Give the Redex a go. I bought my abused 1990 XJ600 in 2006 with 28,000 on the clock and used redex occasionally. Last year (48,000 miles) I stripped the carbs with an older and wiser friend and they were very clean (except where they were completely blocked so nothing got through), there was a lot of crud in the bowls, but that cleaned easily. Some previous user/abuser had adjusted the screws on the pilots, so we counted the turns on each, checked with Mr Haynes and set them all the same as the manual said. Visually checked the opening though the valves and cleaned the crud that prevented them all closing at the same time. Later borrowed a set of vacuum gauges and balanced the carbs. With my XJ, use every day except in snow, it starts with full choke, starts to complain idling after 3 minutes, if have to blip the throttle waiting at lights for the next 5 minutes, then I turn it off. Like someone else said, don't keep the starter on for long, it will also overheat your battery. Link to comment Share on other sites More sharing options...
Recommended Posts