Sunday, 16 December 2018

Engine Start-Up!

This was so rewarding. A definite milestone that put a silly grin all over my stupid fat face.

I guess I could have tried this several months before - even before the gearbox was joined to the engine. However, keen to feel I was making visible progress, I cracked on with other peripheral and superficial jobs instead - such as fitting the ancillaries and pulley belts.

With the car now out of my garage and back at the barn, I was kind of at a loss for further productive things I could do. One thing that had been at the back of my mind though was whether or not the rebuilt engine actually ran! Before the year was out I wanted to know - one way or the other - whether all the effort thus far had been worth it, or whether I would have to start all over again.

In planning to start the engine, one of the first things I needed to do was remove the pulley belts from the ancillaries......With no radiator and cooling circuit, no LHM reservoir and no voltage regulator, I didn't want to be running dry pumps and alternators. So all the set up work had to be undone. I'm sure there's a lesson there for me somewhere. If only I was clever enough to learn it.....

With the engine out of the car, all I can do is a basic set up of the timing (known as 'pre-setting the static timing') - which is only enough to get the engine running. The process for doing this is covered in Operation D.210-0 in Volume 1 of Manual 814. It won't be accurate enough for optimum engine running under normal driving conditions. The actual setting of the  'static timing'  (sometimes also known as 'distributor timing' or 'advance checking') checks for the correct advance of the timing at higher than tickover revs and needs to be carried out with a tachometer and stroboscope.

I had discovered some time ago that my car has got the wrong distributor fitted to it for the engine. My DX engine should have a Dx-05b distributor but has a Dv-010 - as used on D Specials (and then DS23s). I searched but couldn't find the correct distributor so eventually I gave in and bought 123 electronic ignition. It can be set up to mimic just about all (if not all) the mechanical distributors originally fitted to various Ds over the years, by virtue of a small selector hidden behind a hex nut cover. However for the purposes of this trial start up I used my mechanical dizzy. Although not intended for my DX engine, it would be good enough for pre-setting the static timing.

Preparations. With the rocker cover off I lubricated the rockers, shafts and pushrods. Refitting the rocker cover I filled up with 5 litres of engine oil and 2 litres of gearbox oil. Spark plugs were cleaned and the gaps were set. The point gap was set on the distributor.

The first major task was to find the timing firing point. The technique is that a 6mm pin (many people use a twist drill) is inserted in the timing hole under the alternator. 
6mm twist drill in timing hole under the alternator
WITH THE IGNITION SWITCHED OFF AND/ OR BATTERY DISCONNECTED, the engine is cranked using the starting handle or, for five speed cars, by jacking up the front of the car and rotating one of the wheels. It will be easier to crank the engine if you remove the spark plugs. At a particular point, the pin will engage in a shallow slot on the flywheel - locking it in that position. It's easier if you get a willing assistant to press gently on the end of the pin while you crank. 

With the firing point identified, I MADE SURE I REMOVED THE PIN FROM THE HOLE IN THE CRANK and did not turn the engine any more. You don't want to start the engine up and bend the pin in the slot.......

I fitted the base plate to the distributor and loosely tightened the pinch bolt so that I could still, just, rotate the dizzy independently of the base plate.
Base Plate and pinch bolt on the Distributor
I located the distributor lugs of the distributor drive in the grooves in the drive socket at the bottom of the distributor tower. You need to take care when you do this as the lugs and grooves of the drive socket are not central to the axis of the shaft: for the distributor lugs to correctly locate, the distributor shaft needs to be rotated until it is the right way round. It should then push home into the drive socket at the base of the tower.
Drive Tower: as the piston is before TDC, the grooves of the
 distributor drive have not yet rotated parallel to the camshaft line
The lugs on the distributor base are off-centre  - 
there is a 'small half' and a 'big half'
With the distributor pushed home, I did up the nut that holds the plate to the distributor tower. The next step was to correctly orientate the distributor within the tower.

As the engine was out of the car, I rigged up a 12 volt supply to mimic the car battery - though you could just as easily use a car battery! I temporarily mounted the ignition coil on one of the legs of the stand I had made and connected the condenser terminal on the distributor to the negative terminal on the coil. 
Distributor connected to negative terminal of the coil
I took a lead from the positive connection of the power supply to the positive terminal on the coil. The negative of the power supply was earthed to the engine - just as the battery would be.
Power supply to the positive terminal
Using a 12 volt bulb in a holder, and with crocodile clips on leads on it's terminals, I connected one lead to the negative terminal of the coil.......
Test lamp on the negative of the coil
.....and earthed the other end to the engine.

With my power supply (in lieu of a car battery) switched on, I SLOWLY rotated the distributor in an anti-clockwise direction until the test bulb just lit up. I rotated the distributor clockwise a little, then anti-clockwise again until I was satisfied I had found the 'sweet spot' - the point at which the bulb JUST lit up. Like this:
VIDEO: setting the contact opening point

Without moving the distributor anymore I tightened up the pinch bolt on the base plate, then disconnected the power supply.

The point I had just found was the point at which the contact breakers just opened and, since I had started by setting number one cylinder of the engine to it's firing point, I had now pre-set the static timing! - in other words the approximate ignition firing point.

I did a test fit of the distributor cap. It only fits on the distributor one way round as it has a lug that sits in a notch in the distributor body.
Protruding lug on distributor cap edge
Locating notch for distributor cap lug on the distributor body
If you are following this and have done it correctly (firing position of number one cylinder correctly set, distributor correctly located in the drive socket on the tower, distributor rotated until the points just open), the cap will be pointing past the oil filler and back towards number 3 or 4 spark plug.
Distributor cap points towards number 3 or 4 cylinder
Putting the rotor arm on the distributor I could see, and confirm, that the distributor was orientated as I expected it to be. As a rough guide, the rotor should be pointing roughly towards the number one spark plug position of the rocker cover. This was the firing position for number one cylinder.

Rotor arm points roughly towards number one spark plug
With the number one firing position determined, by matching the rotor arm position just established to the contacts inside the distributor cap, I could identify which HT lead position on the cap needed to go to number one cylinder. The firing order of a DS is 1,3,4,2,  and the rotor arm rotates clockwise so, working around the cap, I could also then work out which HT lead positions needed to go to which other cylinders. 
Knowing which contact aligns to no.1 spark plug, the rotation of the
 rotor and firing order, the location of the HT leads can be worked out
I connected the HT leads and refitted the distributor cap. I fitted a short length of wire to the choke pulley on the carb.
I rigged up a choke cable
I rigged up my car battery, connecting the positive to the starter motor lead and also running a cable round to the positive of the coil. The negative from the battery was earthed to the chassis. I took a length of fuel pipe from a can of fuel into the fuel pump and I was all ready to go......
My car is a 1968. Note the positions of the battery terminal posts
Using the piece of wire I had fitted I set the choke. I used the button on the bottom of the 'daisy' on the battery terminal to start the car.  It took quite a bit of turning over to prime the petrol pump and carburettor, as both had been rebuilt and were bone dry inside.  When the car did eventually start, it startled me: with no exhaust it was loud.

With the choke engaged it ran fast and I quickly put the choke off to slow the engine down. I gently blipped the throttle a couple of times but didn't let the engine run for more than about 10 seconds. I was worried that with no coolant it would overheat. 

I made a cup of tea and came back for seconds - and with a video camera this time. This was how it went:
VIDEO: Trial Start-Up

I'm very pleased with the experiment. Even though it sounded more like a tractor than a DS, the engine seemed to run smoothly and with no missed 'beats'. And even though it was stone cold, I reckon it would have ticked over quite happily - well, at least until it seized!

I discovered I had a fuel leak from under the lid of my rebuilt fuel pump. Turns out some idiot had failed to screw the lid on tightly enough. That wiped a little of the silly grin off my face, but a further test run confirmed all was now working fine and with no fuel leak.

I will set up the timing properly once the engine is back in the car. I plan to follow the settings of the factory manual, but need to work out how I adjust any settings to compensate for modern unleaded fuel and possible engine 'pinking' - which can damage the engine. When I eventually get to that job, I THINK that the timing will need to be retarded more than the factory settings to compensate for the use of unleaded fuel - which ignites more slowly (fractions of a second) than leaded fuel.

Even though I have 123 electronic ignition to fit, it's good practice to carry a spare distributor with you. With that in mind I might strip and rebuild my mechanical dizzy and keep it in the car for emergencies. I'm pretty sure there are instructions for a rebuild in manual 518.

12 comments:

  1. Good job Paul,
    Great to see some videos, looking forward to meeting you and your car sometime.

    Have a good new year.

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  2. Thanks Colin. Appreciated. I'll be at the D rally and the UK '100 years' celebration I expect.

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  3. I'll will definitely be going to Coventry... I will call you nearer the time.

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  4. Without pressure the wheels shouldn’t turn, or not? However the clutch is engaged, the gearbox should be in neutral...

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  5. Hi Andrew. Not sure I understand you. I think you are referring to the video? I hadn't adjusted the clutch in any way in terms of drag. From what i can remember, the two shafts rotated in different directions! It wasn't really a test of the set up of the clutch or gearbox.

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  6. Hi Paul, I just wondered why the axles were turning. (In the video indeed) There must be a gear selected. Normally, in a pressureless system the clutch is engaged but there is no gear selected. (Neutral)

    Nice project btw. I am restoring a similar ds (1969)

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  7. Thank you Andrew. You might be right and I will need to check, but i did find a video of another car doing the same thing. It is manual gear change and presumably also in neutral. Who knows! https://www.youtube.com/watch?v=8MFWSgZusVI

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  8. Maybe it’s just some friction which stops when the wheels hit the ground.

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    Replies
    1. Yes, I think that is what i decided at the time. i will find out soon enough!

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  9. Meus cumprimentos! obrigado pelo esclarecimento.

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  10. O prazer é meu. Ainda bem que foi útil.

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  11. Followed your very clear procedure for setting the static timing today. All went well. Thank you for making it very simple and straightforward.

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