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didn't disconnect the vacuum pipe!
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aha not as old as me then ;)
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maybe it's the beer thats not helping me oldman! I will try again with the pipe disconnected. Incidentally with 3 in 1 in the dashpots got reasonable response, with engine oil (cant remember the grade but thicker), seemed to get better response but also the comedy backfires after about 2500rpm. Sorry to keep bugging you but the advice is appreciated as after a while i get lost!
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3 in 1 is probably too thin, gear oil is too heavy. Normal engine oil or ATF should be fine......
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I agreee with oldman 20/50 is fine, though I seem to recall it was supposed to be a straight grade, either 20 or 30. Everyone in the 70's put 20/50 in though. I always found the timing a bit suck it and see with those engines. Start at 8deg, but you want as much advance as you can give it without it pinking. Might be less tahn 8 as they ran on 5 star in those days. Mike
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hmm, all sounds like good advice to me. Interesting point there mike, i always thought (for some reason), that the timing setting was finite for each engine so will experiment as suggested. By advance do you mean i might want more than 8" BTDC as in goes bang earlier or the other way as in less degrees BTDC or am i misunderstanding what's going on here? Possibly a case of a little knowledge is dangerous?
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no mike is basically right set it at static and take it for a blast.............
then do subtle adjustements if it pinks or feels retarded..........
all motors pre ecu"s had to be set this way especially cars like your good selfs,id actually forgot the "5" star angle : (
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takes me back to doing plug chops at the side of the road
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thanks oldman will do as suggested. BTW didn't mean to imply that mike was wrong - just not really sure where i'm going here.
Sorry to keep pestering you all but is there a best order of things for setting up, e.g timing 1st, points gap 2nd, something else 3rd and so on or does it not matter as long as they are all set correctly?
Ta
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Yes there is an absolute order, points gap or preferably dwell angle first, if you have a meter. Then timing. Adjusting the points gap will affect the timing, lower gap advances the ingition. This naturally happens as you run the engine, which was one of the problems with points. The heel of the point wears, and gradually advances the timing, get pinking / over heating, re-set them. Continuing cycle.....
I remember a lightweight E type that I used to look afer could take about 12 deg static advance, but we used to set it at revs on full advance afeter that. Noisy!
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too many wines, retards the timing, sorry! oops!
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Confusing perhaps:
Bigger gap = lower dwell angle. Coil switched on for less time, Coil switched off for more time.
Smaller gap = higher dwell angle. Coil switched on for more time, Coil switched off for less time.
Ignition timing retards as points wear and gap gradually closes, resulting in gradual loss of performance. This is where electronic ignition scores over the conventional system. The module increases dwell angle with engine speed whereas with points it remains the same, which is exactly what you don't want.
I'd consider fitting an electronic ignition system to your car. Not only would you never have to worry about points and condensers ever again, you'd find it'd start easier and maintain performance and the dwell angle and ignition timing would never go out. Lumenition kits were really good are are still available. I 've had two on two different cars of my own and attended cars at the roadside with them fitted, and I've never known one to fail.
www.lumenition.com/
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When you take the vacuum pipe off, plug the hole. A vacuum leak will upset things somewhat.
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I've used Lumenition on several cars-excellent,well-made easy to fit and once fitted you never have to go near it again-ever.
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I once spotted a bottle of what was labelled as SU dashpot oil at an autojumble and bought it for the SUs on my Daimler and Rover V8s. It vanished quicker than 3in1! Went straight back to Duckhams 20/50 and had no more trouble...
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thanks guys - you're all a great help. I will be out there later and see how it goes. Mike H mentioned "dwell angle", this is something i've heard of but dont know how to set. I have a multimeter if that's any good.
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You cannot do dwell angle with a multimeter Phil as far as I';m aware, you need a dwell meter do do it. Don't worry about it though, unless there is something horribly wrong with the cam on your distributor, then setting the points gap to the correct gap should automatically put the dwell angle within tolerance. As previously stated, it counts the amont of time the points are closed, allowing the coil to re-charge fully, so you get a nice fat spark. Don't forget a tiny smidgin of grease on the cam to prolong heel life.
Set the static timing , mark the distributor body to the block, go for a spin. If it's not pinking, turn the distributor a little against the direction of rotation comparing with your previous mark, and try again. If it pinks , reverse the process. I would second all the advice on electronic ignition however, a gint step forward. I put boyer on my 650 Bonneville for the very reasons mentioned! Mike
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Dwell angle is the term given to the number of degrees the ignition coil is switched on. The distributor cam rotates through 360 degrees (fairly obvious eh) so for a six cylinder engine 360/6 = 72. This figure would represent the coil permanently switched on, ie points closed all the time.
So if the correct dwell angle figure for your car was say 40 degrees, the coil would be 'on' for 40 degrees and 'off for 32 degrees per cylinder. A multi-meter with duty cycle could also be used to measure the amount of time in milliseconds the coil is switched on/off. Ideally the longer the coil is 'on' the better, but mechanical points cannot alter as conditions require, and coil 'on' time would effectively shorten as engine speed increases, which means that the HT spark would get weaker. So this system is known as 'constant dwell'. Also at high speed there is the possiblity of the points not being mechanically able to close in time for the next coil build up. This is known as 'point bounce' and will cause the engine to misfire.
Electronic systems vary the dwell angle with engine speed and thus matching coil 'on' time to suit all conditions maintaining performance throughout the entire rev range, and point bounce doesn't happen.
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Couldn't have put it more eloquently myself railroad! The luminition system we've mentioned earlier however is not fully electronic. It replaces the points with an optical sensor so eliminates the wear, but still relies on the mechanical advance rather than full electronic advance as we have come to expect. Still a very worthwhile mod unless you are a stickler for originality.
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It's not really got anything to do with mechanical advance, it's to do with varying the ignition coil on/off ratio. Most electronic systems using a mechanical distributor will still use bob weights for centrifugal advance, as well as a vacuum operated diaphragm. The pickup is usually either the hall effect or inductive pulse type.
The optical sensor on a lumenition does not directly switch the coil but the module, and the module switches the coil....
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Also forgot to mention if you did change your points & condenser for an electronic system you'd also need to change the ignition coil. The is because the primary resistances between coils designed for points and electronic systems are different.
Primary resistance of coil for a points system would be about 3 ohms, whereas an electronic system coil would be <1 ohm. If you fitted an electronic coil with points you'd find the points would burn very quickly as the current passing across them would be fairly high, due to the low resistance of the primary windings.
If you fitted a conventional coil with an electronic system performance would tail off at high speed due to the magnetic field taking longer than necessary to build up, due to the high resistance of the primary windings.
To check which one you have disconnect the coil terminals '15' & '1' (+ & -) and connect an ohmmeter.
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you do not need to change the coil if you fit Lumenition;it effectively just replaces the points-the rest of the system is unchanged.
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Would be better if you did though. The lower resistance primary windings of an electronic ignition coil means the magnetic field would build up and collapse quicker than on a conventional ignition coil, thus maintaining correct plug firing voltage and far reducing the possibility of misfire at high speed.....
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Lumenition wouldn't be my choice, know of too many failures these days also damned expensive for what it is.
I'd go Aldon ignitor which fits entirely within the dizzy cap. Coil can remain standard as that is what it was designed for. I know loads of people with these 100% reliability & a doodle to fit!
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Would be better if you did though. The lower resistance primary windings of an electronic ignition coil means the magnetic field would build up and collapse quicker than on a conventional ignition coil, thus maintaining correct plug firing voltage and far reducing the possibility of misfire at high speed.....
Correction. The Lumention Optronic unit must not be used with an electronic ignition coil as the low resistance windings would draw more current than the module is designed for, and cause damage to it. So clearly not the ideal system to use.
The Lumenition Performance unit however is designed for use with electronic ignition coils, but at £250 seems quite expensive.
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