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Post by tommydp on Jun 8, 2011 21:09:44 GMT
Hi all! Can anyone shed some light on the correct way of installing 1800 mk 2 front hub bearings? Do you really need to have them pressed onto the hub etc, using special tools as stated in manuals? If so, are there universal tools for this job? I suppose the original tools are long gone, at least up here:-)
I've changed bearings on one side, using no special tools. It seems fine, it's tightened to correct torque. There is no slack. However, I believe there's a slight rumbling sound there. It is not worse when turning left or right. Also there's some vibration when braking at high speed. There's also some visible wobble when turning wheels by hand, on all four wheels actually..
I've had the wheels and tyres checked for balance, and they're fine. Are wobbling wheels acceptable? I seem to have this on all my crabs:-) Other than slight vibrating/ loose feeling at steering wheel when braking at high speed, the car is pleasant to drive. Sometimes there's also a sideway shake at slow speed, typical in city driving, start- stop driving, creeping between traffic lights etc. This seems to come from the rear end, no shake at steering wheel. The shake goes away when speeding up. There's also some vertical jumping now and then. No brakes are binding btw.
All other steering and suspension parts are new and correctly adjusted, there's no slack any where. Using my brilliant Hydrolastic pump included with the crab I just bought, I've also re- pressurized the suspension, pulling vacuum before filling up. It made a big difference! Ride height is spot on.
Well, I know this is an old car, but I want it perfect:-) Believe me, it's very pleasant to drive, but I'm a bit annoyed by these steering/ suspension issues, especially the rear end shake which must be evident to those driving behind:-( Once sorted, the car will be absolutely perfect even to my high demands:-) I'm also planning a holiday with it, and do not want to get stranded with a broken wheel bearing etc:-)
Regards, Tommy
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Post by dave1800 on Jun 9, 2011 8:35:41 GMT
Hi Tommy As I am 6 hours ahead of the UK (I think 5 hours for Norway) I am going to reply first. It is possible to assemble the front wheel bearings without the correct tool, I have done it in the past it's just important to be able to press the bearings in all the way and properly aligned. The judder under braking could be run out of the disk, you should check this with a dial guage or a sticking piston. As far as the rumbling is concerned if it doesn't get worse when turning are you sure you packed it with sufficient grease? Hope you've not got a bad bearing. I am baffled by the fact that all your crabs exhibit wheel wobble on all four wheels. You need to recheck the wheel bearings and use the dial guage to measure any out of true running or free play. Other than when I have had a wheel bearing or hub splines / cone washer fail I have never experienced this even on a car with over 250,000 miles on it. If the bearings run true then this points to the wheels and or tyres - I recall you had some issues earlier about tyres. Of greater concern is the rear end shake at low speed. Have you checked the rear suspension slipflex bearings (I assume it's a Mk11 car)? Is the wheel rubbing agsinst the inner wing for example - easily spotted a clean and maybe shiny area. Double check all the suspension mounting bolts. It could also be just a faulty tyre; if you have spare wheels then substitution is the quickest way of checking. I know I've not been much help here this time, but hopefully others will chip in. Regards David Hi all! Can anyone shed some light on the correct way of installing 1800 mk 2 front hub bearings? Do you really need to have them pressed onto the hub etc, using special tools as stated in manuals? If so, are there universal tools for this job? I suppose the original tools are long gone, at least up here:-) I've changed bearings on one side, using no special tools. It seems fine, it's tightened to correct torque. There is no slack. However, I believe there's a slight rumbling sound there. It is not worse when turning left or right. Also there's some vibration when braking at high speed. There's also some visible wobble when turning wheels by hand, on all four wheels actually.. I've had the wheels and tyres checked for balance, and they're fine. Are wobbling wheels acceptable? I seem to have this on all my crabs:-) Other than slight vibrating/ loose feeling at steering wheel when braking at high speed, the car is pleasant to drive. Sometimes there's also a sideway shake at slow speed, typical in city driving, start- stop driving, creeping between traffic lights etc. This seems to come from the rear end, no shake at steering wheel. The shake goes away when speeding up. There's also some vertical jumping now and then. No brakes are binding btw. All other steering and suspension parts are new and correctly adjusted, there's no slack any where. Using my brilliant Hydrolastic pump included with the crab I just bought, I've also re- pressurized the suspension, pulling vacuum before filling up. It made a big difference! Ride height is spot on. Well, I know this is an old car, but I want it perfect:-) Believe me, it's very pleasant to drive, but I'm a bit annoyed by these steering/ suspension issues, especially the rear end shake which must be evident to those driving behind:-( Once sorted, the car will be absolutely perfect even to my high demands:-) I'm also planning a holiday with it, and do not want to get stranded with a broken wheel bearing etc:-) Regards, Tommy |
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Post by tommydp on Jun 9, 2011 11:28:13 GMT
Thanks, Dave! Helpful as always:-) Well, I suspect the rear Slipflex bearing(s), too. I'll have a look at them. I still have the cheap, far East tyres, which could give som wobble, I'm sure. I'll try to get some new ones. yes, all wheels seem to have some run out when spinning them around, typically one sideway shake on each revolution. Same thing on the rear wheel of the crab I just bought, however, there was slack in that bearing.
There is no slack in the bearings on the crab in question. I'm afraid I don't have a dial gauge. I'll get one later.
Tommy
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Post by tommydp on Jun 9, 2011 22:19:39 GMT
Went to get a dial gauge this evening, but sadly they were sold out. Hope to get one soon, though.
In the meantime, can anyone please guide me into checking true running, end play etc of hub bearings, front and rear, using a dial gauge. All I've ever done checking wheel bearings is grabbing wheel at 12 and 6 o'clock, checking for free play. I believe there should be no noticable play here on the crab. There is no play here, and I've tightened to correct torque on all wheels. I've searched the net, but I'm still no wiser regarding using a dial gauge to check bearings:-) I understand how to check the brake disk. I'm not to concerned about the brake judder. After all, it's a light judder and occurs only at speeds above 80 kilometres pr hour.
It will be interesting to investigate the reason for the wheel wobble/ out of true running and confirm if the trouble is due to the hubs or wheels. I suppose the gauge can be used to check the running of the driveshaft too. I believe they are still running out of true.
It might be worth mentioning that there is an occasional single click, when taking off from standstill. Both forward and in reverse. There are no clicks or other noises when driving on full lock, either way.
Well, only these things to rectify now, and once sorted I'm pretty sure the car is mechanically nearly as new. The bargain lot I got last week also included a very good steering rack, which I have installed. No more rattles, and a very steady and nice steering. So, there is some progress:-) The engine is marvellous still, I'm extremely pleased with the fuel consumption as well as its performance. One thing that puzzles me is, the coil still gets hot. There are no misfires or cutting out etc, and it pulls very smoothly so I really don't care. The coil on the crab I just bought stays cool all the time in that car. I tried this coil in the other one, and it went hot after about 5 minutes of idling.
Well, as I said, I don't really care. However I'm always eager to find the reason for such things:-) Anyway, wheel bearings and wobble etc first:-)
Regards, Tommy:-)
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Post by dave1800 on Jun 10, 2011 1:25:31 GMT
This could be the CV joint or possibly the drive hub starting to move on the splines - recheck and tighten hub nut if necessary. It might be worth mentioning that there is an occasional single click, when taking off from standstill. Both forward and in reverse. There are no clicks or other noises when driving on full lock, either way. One thing that puzzles me is, the coil still gets hot. There are no misfires or cutting out etc, and it pulls very smoothly so I really don't care. The coil on the crab I just bought stays cool all the time in that car. I tried this coil in the other one, and it went hot after about 5 minutes of idling. The only reason a coil runs hot is too much current - which can mean the dwell is wrong, the wrong type of coil meant for a ballasted system - or there is a short inside the coil windings. Have you tried measuring the primary resistance to see if it is out of spec? Is it a standard coil? I would advise you NOT to use this coil as if it is breaking down it will get worse and leave you stranded. If I read your message right, it gets hot on both of your cars. Well, as I said, I don't really care. However I'm always eager to find the reason for such things:-) Anyway, wheel bearings and wobble etc first:-) Hopefully some others will post. In the meantime have a look at problems encountered in Oz with front hubs, a useful tip about ball joint shims if you ever encounter problems with wheel bearing loading groups.google.com/group/austin1800/browse_thread/thread/1c410bb0a1a85f86#Regards David Regards, Tommy:-) |
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Post by tommydp on Jun 10, 2011 5:45:02 GMT
Thanks! Sorry, I was a bit unclear about the coil. It gets hot in this car only. I also tried the coil from the other crab, wich stays cool in that one. It too went hot. I've also tried other coils, they all go hot. Resistance is fine, about 3,5 Ohms. Dwell is 60 degrees, spot on.
Regards, Tommy.
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Post by tommydp on Jun 10, 2011 6:18:57 GMT
Come to think of it, perhaps the alternator is putting out too much current. I'm using a Bosh unit from a Ford Granada, as I've always found them very reliable and easy to fix because of the combined regulator and brush box, which can be changed in seconds. It's fitted with a 13,7 Volts regulator, but the current will be too high anyway, I guess.
I suppose the problem lies here. Perhaps I'll go for a 16 ACR unit or something, after all. I always keep a spare coil in the boot btw:-)
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Post by dave1800 on Jun 10, 2011 7:19:55 GMT
Hi Tommy This is most strange. Having a high power alternator should make no difference to the ignition coil heating. The alternator voltage regulator is set at around 13.8 volts no matter whether you have a 40A or 200A alternator. The average current consumed by the coil = V/R x the dwell. The heat generated in Watts = V*I. If there is a problem and the voltage is much higher you would be burning out light bulbs. But worth double checking the voltage as you are getting the same effects with both coils on this one car. Regards David Come to think of it, perhaps the alternator is putting out too much current. I'm using a Bosh unit from a Ford Granada, as I've always found them very reliable and easy to fix because of the combined regulator and brush box, which can be changed in seconds. It's fitted with a 13,7 Volts regulator, but the current will be too high anyway, I guess. I suppose the problem lies here. Perhaps I'll go for a 16 ACR unit or something, after all. I always keep a spare coil in the boot btw:-) |
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Post by tommydp on Jun 10, 2011 8:32:37 GMT
Hi Tommy This is most strange. Having a high power alternator should make no difference to the ignition coil heating. The alternator voltage regulator is set at around 13.8 volts no matter whether you have a 40A or 200A alternator. The average current consumed by the coil = V/R x the dwell. The heat generated in Watts = V*I. If there is a problem and the voltage is much higher you would be burning out light bulbs. But worth double checking the voltage as you are getting the same effects with both coils on this one car. Regards David Come to think of it, perhaps the alternator is putting out too much current. I'm using a Bosh unit from a Ford Granada, as I've always found them very reliable and easy to fix because of the combined regulator and brush box, which can be changed in seconds. It's fitted with a 13,7 Volts regulator, but the current will be too high anyway, I guess. I suppose the problem lies here. Perhaps I'll go for a 16 ACR unit or something, after all. I always keep a spare coil in the boot btw:-) Ok! Great, I'll keep the Bosch alternator then. Hard to find the reason for this, perhaps something to do with the conversion to negative earth. However I've done that earlier and had no trouble. The coils are the correct HA 12 units. I've even tried a ballast one with the ballast wiring from a Marina. It too gets hot. Voltage at battery at idle is approximately 13.8 Volts, no bulbs have ever failed. No lights flicker etc, no current leak. Voltage at + on coil is about 13.4 at idle. At - (to dizzy) it's about 6 Volts idling. This is the difference I can find, compared to the 'cool coiled crab'. Voltage at - is higher on this one when idling. That car too has been converted to negative earth. Regards, T |
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Post by dave1800 on Jun 10, 2011 11:44:46 GMT
If the voltage on the coil(s) at the (-) terminal is higher when idling on this particular car then I would suspect the dwell is too high allowing the "average voltage" as measured at the (-) coil terminal to rise and dissipate more heat in the coil, BUT your figure of 6 volts doesn't indicate this is the case. Did you measure this with an analogue meter? A digital meter will not give a true average voltage reading as it takes samples at fixed intervals. It would be helpful if you could double check all the voltages and dwell settings and confirm the issue is CAR related rather than coil. regards David quote author=tommydp board=tech thread=180 post=1050 time=1307694757] Hi Tommy This is most strange. Having a high power alternator should make no difference to the ignition coil heating. The alternator voltage regulator is set at around 13.8 volts no matter whether you have a 40A or 200A alternator. The average current consumed by the coil = V/R x the dwell. The heat generated in Watts = V*I. If there is a problem and the voltage is much higher you would be burning out light bulbs. But worth double checking the voltage as you are getting the same effects with both coils on this one car. Regards David Ok! Great, I'll keep the Bosch alternator then. Hard to find the reason for this, perhaps something to do with the conversion to negative earth. However I've done that earlier and had no trouble. The coils are the correct HA 12 units. I've even tried a ballast one with the ballast wiring from a Marina. It too gets hot. Voltage at battery at idle is approximately 13.8 Volts, no bulbs have ever failed. No lights flicker etc, no current leak. Voltage at + on coil is about 13.4 at idle. At - (to dizzy) it's about 6 Volts idling. This is the difference I can find, compared to the 'cool coiled crab'. Voltage at - is higher on this one when idling. That car too has been converted to negative earth. Regards, T[/quote] |
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Post by tommydp on Jun 10, 2011 15:01:56 GMT
I'm quite sure the hot coil issue is car related, as I've tried a lot of different correct coils and they all turn hot in this car. They have turned hot ever since I got this car running again three years ago. They will turn far more than lukewarm. I don't burn my hand on it, but they are more hot than normal for sure. After about 5 minutes of idle, the coil will go from ice cold to lukewarm, then just go hotter and hotter. I have no misfire issue however, idling or driving.
Well, I did some testing now, using a digital meter as well as a Gunson's analogue Testune instrument. I checked the well functioning car, as well as the failing one. Only difference between the two is the well functioning one has a 45 d dizzy, the bad one has a 25 d. They both have standard 12 v coils, no ballast resistors etc. Here are the results:
Well functioning crab, keeping coils cool:
Volts at battery, idling: 14,0 digital, 14,0 analogue
Volts at + of coil, idling: 13,4 digital, 13, 4 analogue
Volts at - of coil, idling: 8,6 digital, 8,0 analogue some judder both
Resistance, coil: 3,7
Dwell: 55%= 49,5 degrees if I did my maths correctly? Normal for a 45 d I suppose?
Failing crab, heating coils:
Volts at battery, idling: 13,85 digital, 13,8 analogue
Volts at + of coil, idling: 13,27 digital, 13, 3 analogue
Volts at - of coil, idling: 6,0 digital, 6,2 analogue some judder both
Resistance, coil: 3,4
Dwell: 68%= 61,2 degrees if I did my maths correctly? Normal for a 25 d I suppose?
On both cars Volts at negative terminal of coil will rise when revving.
Well, does this say something?
Regards, Tommy:-)
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Post by dave1800 on Jun 11, 2011 0:51:27 GMT
Your calculations are spot on! You could try setting the dwell on the overheating coil car to 50 degrees. It shouldn't cause any problems unless you drive with the engine running over 6,000 rpm and possibly get contact bounce. If this stops the coil overheating you have a solution if not a definitive answer of the cause - remember to reset the timing to compensate. As the points cam wears it will tend to raise the dwell a little. It could be that you are at a point where the heat loss is just slightly less than the heat gain so the heat builds up. Reducing the on time of the coil a little could shift this equation. If you rev the car the dwell should not change significantly, ideally it should stay the same. You mentioned previously that you have changed from + earth to -. Did you change the coils to those designed for negative earth? Internally one end of the primary is conected to the "cool" end of the secondary coil. This is the "wrong" end if you use the original + earth coils and they run less efficiently, but this wouldn't affect the heating issue. After checking this, I think you should find the cause of the rear end shake in case there is something that requires urgent attention. My only experience with a failed slipflex bearing was that the rear squealed and hopped under tight cornering, but I would imagine a whole range of symptoms could present themselves. Good luck regards David I'm quite sure the hot coil issue is car related, as I've tried a lot of different correct coils and they all turn hot in this car. They have turned hot ever since I got this car running again three years ago. They will turn far more than lukewarm. I don't burn my hand on it, but they are more hot than normal for sure. After about 5 minutes of idle, the coil will go from ice cold to lukewarm, then just go hotter and hotter. I have no misfire issue however, idling or driving. Well, I did some testing now, using a digital meter as well as a Gunson's analogue Testune instrument. I checked the well functioning car, as well as the failing one. Only difference between the two is the well functioning one has a 45 d dizzy, the bad one has a 25 d. They both have standard 12 v coils, no ballast resistors etc. Here are the results: Well functioning crab, keeping coils cool: Volts at battery, idling: 14,0 digital, 14,0 analogue Volts at + of coil, idling: 13,4 digital, 13, 4 analogue Volts at - of coil, idling: 8,6 digital, 8,0 analogue some judder both Resistance, coil: 3,7 Dwell: 55%= 49,5 degrees if I did my maths correctly? Normal for a 45 d I suppose? Failing crab, heating coils: Volts at battery, idling: 13,85 digital, 13,8 analogue Volts at + of coil, idling: 13,27 digital, 13, 3 analogue Volts at - of coil, idling: 6,0 digital, 6,2 analogue some judder both Resistance, coil: 3,4 Dwell: 68%= 61,2 degrees if I did my maths correctly? Normal for a 25 d I suppose? On both cars Volts at negative terminal of coil will rise when revving. Well, does this say something? Regards, Tommy:-) |
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Post by tommydp on Jun 11, 2011 7:08:43 GMT
Thanks again. I didn't realise there were different coils. I'm using a rather new Lucas DLB 101 at the moment, which I believe should be fine. I've also tried coils of different brands with approximately 3,5 Ohms resistance, and they all turn hot. I even tried the negative earthed Marina ballasted coil with the ballast wire, and it too went hot. Could there be something interfering/ disturbing the current coming to the + of the coil? Slight contact with earth/ arching etc? I can't think of anything else causing this. I'm absolutely sure the dizzy is fine, its internal wiring, engine earth etc. I've tried different distributors too. I suspect the wiring behind the dash/ connection at A3 and A4 terminals etc. I've never seen any obvious fault and all electrics work as they should. Nothing gets hot etc. However, the car stood in a shed for many years, no doubt even mice could have been chewing on hidden wires:-)
I had some issues related to electrics and the A3 A4 terminals when putting the car together and converting to negative earth. I know the wire from the ignition switch to coil is independent of the fuse, however if something disturbs the fused circuits of this terminal, it will disturb the wire to the coil to, I guess? The trouble I had was: Wipers would occasionally not stop/ selfpark and the heater ran less efficiently than with positive earth. Also, if stopping the car, turning key off, with heater on the car would run on for a second or two! Reading about this on an MG site or something, I switched the green and black wires at the heater and it ran as it should. It doesn't run on anymore, however the heater is now connected to an aux connection, as the radio, on the ignition switch. I have a later type ignition switch for some reason.. Well, I'll have a look into all this once again later, strange I've never had a fuse blow or any other electrical problems exept the hot coil issue.
Regarding the rear end shake, it's not been evident lately. Don't know why. As it behaves now there doesn't seem to be anything seriously wrong, but I'll have a look for rubbing marks behind the rear wheels later. I'm wondering if re- pressurising the suspension has made some difference, especially the fact that I was able to evacuate the system with vacuum using my "new" pump. At least, the rear end is not as saggy as it was and the ride is far softer. I even had the front end tracking adjusted by a garage yesterday. It was quite a bit off, after installing the "new" steering rack. Steering is now fabulous, very steady even at the highest speed I ever travel at.
The hub nut of the slightly rumbling fornt wheel, as described earlier was loose. Correct again, Dave! Not badly loose, but not to 150 torque. Seems the click dissapeared.
Regards, Tommy
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Post by dave1800 on Jun 11, 2011 9:53:08 GMT
Thanks again. I didn't realise there were different coils. I'm using a rather new Lucas DLB 101 at the moment, which I believe should be fine. I've also tried coils of different brands with approximately 3,5 Ohms resistance, and they all turn hot. I The circuit is so simple, the +ve power via the ignition switch to the coil and earthed via the contact breaker. If there was any other leakage to earth the car would almost certainly not start. You could try wiring this hot coil in series (low tension side) with the coil that stays cool from the other car making a resistance of somewhere around 6-7 ohms and connect to the battery + and - terminals this would be the equivalent of 50% dwell to see if both coils heat up equally. If the hot one stays cool then I suggest setting the dewll to 50% and re-time the ignition. (Connect coil one + to battery +; coil one - to coil two +; and coil two - to battery -. It doesn't matter which you choose to be coil one the hot or cold). The hub nut of the slightly rumbling fornt wheel, as described earlier was loose. Correct again, Dave! Not badly loose, but not to 150 torque. Seems the click dissapeared. I would advise you keep checking this hub nut for signs of working loose every couple of weeks or lerss for a while in case there is wear in the drive hub / CV joint splines. If it does work loose there is quite a lot of info on the link I posted earlier about how to save the drive flange and bearings from failure. (I have sent you a PM with a link to some good descriptions of the ignition system) regards David |
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Post by dave1800 on Jun 12, 2011 2:20:14 GMT
Well functioning crab, keeping coils cool: Volts at battery, idling: 14,0 digital, 14,0 analogue Volts at + of coil, idling: 13,4 digital, 13, 4 analogue Volts at - of coil, idling: 8,6 digital, 8,0 analogue some judder both Resistance, coil: 3,7 Dwell: 55%= 49,5 degrees if I did my maths correctly? Normal for a 45 d I suppose? V=13.4 R= 3.7ohms I = 3.6 amps. Power V*I*Dwell% = 27 watts Failing crab, heating coils: Volts at battery, idling: 13,85 digital, 13,8 analogue Volts at + of coil, idling: 13,27 digital, 13, 3 analogue Volts at - of coil, idling: 6,0 digital, 6,2 analogue some judder both Resistance, coil: 3,4 Dwell: 68%= 61,2 degrees if I did my maths correctly? Normal for a 25 d I suppose? V=13.3 R= 3.4ohms I = 3.9 amps. Power V*I*Dwell% = 35 watts Well, does this say something? If you apply 35 watts to a coil then it will get hot! Just leave 2 15 watt brake light bulbs on for a few minutes - don't touch the glass! Those additional 8 watts (35-27) could make the difference. The coil case and the internal oil will act as a heat sink which will rise in temperature while losing heat to the air and the car body where it is clamped; think of an equilibrium where the loss = the gain a coil remains cool but once the gain exceeds the loss the temperature will rise. In practice the coil current will fall as its temperature rises so it becomes less efficient, but I've kep the calculations simple. The outside temperature here is ranging from 33C to 38C so everything feel hot - perhaps others can measure their coil temperature compared with ambient and you can do the same. Regards, Tommy:-) |
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