Technical After the rebuild

[JakeF]

Hi,

Got gearbox and engine fitted today. Quite a job alone! Bolted everything on checked everything twice, checked ignition. Ok, all should be fine for firing the motor .
Nothing! Crap, what now. I had unconnected the fuel line from the tank, hose back on and a new try. The engine started almost at first turn! Wou!

A couple of things I would like to ask. The generator light stays on when the car idles. Lets say, before the engine strip in went off 1000rpm(about). Now it stays on but goes off maybe at 2000-2500rpm?

What can cause this, did not touch the generator during my rebuild. I noticed when I took the engine off that there was one maybe 20cm wire hanging from under the generator(there is a mounting for this). What is it for, now its missing?
Can a low voltage battery cause this light problem. Shouldn't the light go off just like before, after about 1000rpm? The two wires is connected correctly to the generator, nothing else.

Didn't get the ignition(points ignition) to correct position, the engine did not run very well, some stalling, strobo problems. Im going to fit the 123 ignition so this will sort this.

 

[Bambino]

Hi Jake,

Sorry to hear that you are having ongoing problems.

The warning light for either a generator or an alternator is wired so that it receives a voltage from both the switched ignition (12V) on one side and the field winding on the other. When the generator is running at low speed, a current will run through the light and it will glow - this is normal. As the generator rotates faster the field voltage builds up until it matches that on the ignition side of the warning light and the bulb will not glow. This happens at around 1200rpm (~ cut in speed).

If the light is remaining on, you should not be driving the car until you fix the problem as you can badly damage either the wiring or the regulator or both.

Is any of the wiring or the regulator itself getting really warm when the car is running?
What voltage are you getting at the battery?

There has already been a fair bit written in this forum about generators etc. Have a look at

https://www.fiatforum.com/500-classic/209605-generator-alternator-conversion.html (post #9)

and

https://www.fiatforum.com/500-classic/304719-generator-question-500n-1958-59-a.html (post #6)

These may help, if not, there is also an Electrical Engineer (Matt's Dad) on the forum who occasionally posts. He can correct any of my inaccuracies

The wire hanging down could be the wire to anything or an earth braid or something else. Got a photo or description - colour, thickness etc.

Chris

 

[JakeF]

Chris,

Thanks for these links! I need to measure the voltage from the battery and test the wires/generator from warming.
Can a low voltaged battery cause the light remain on at low speed? Did not measure any volts yet.

The voltage regulator can cause this also? In this part what should I check. I unmounted it during my engine rebuild.
Im actually very bad at electrics, always been

I should also clean the wire contacts for sure.
Is it possible to unmount the generator without removing the whole engine? Just got the engine back

Should I first sort out this problem before fitting the 123 ignition, can it be damaged? Are these connected to each others? She runned abit poorly but I assumede it was the advance?

 

[jjacob]

Hi Jake,

The light staying on longer may be because the generator belt is loose, or the voltage regulator is out of adjustment, or needs to be replaced. A low voltage battery would not change the rpm that the voltage from the generator rises at.

The wire dangling from the bottom of the generator is a ground. This wire is attached to the generator mounting strap bolt (#16044321 in the picture) and goes to the left hand side (facing the engine) lower rear panel mounting stud.
See attached picture.
John

 

[JakeF]

Thanks John, what is the ground wire for? I assume, that if its a electric "leak" it goes to ground, any sense .

I need to check the voltage regulator. It was dismantled, maybe a wire is abit loose or bad contact. The belt is ok, tried with two different tightness.
Haynes says "undercharging may become apparent as a flat battery" I dont really understand this, Any help?

I'll check the wires etc and if no help I assume the first thing is to get a new regulator. It's not very easy to adjust it home without experience and correct tools!?
I can only find electrical voltage regulators?
http://www.fiat500ricambi.com/fiat500/Dynamo+and+starter/MO1027


But, should I resolve this first before fitting the 123 ignition, can it be damaged?

 

[jjacob]

Thanks John, what is the ground wire for? I assume, that if its a electric "leak" it goes to ground, any sense .

All engines have a ground wire or strap that goes from the engine to the chassis. If you think about it the engine is electrically isolated from the chassis by the motor mounts.

I need to check the voltage regulator. It was dismantled, maybe a wire is abit loose or bad contact.

This sounds like it might be your problem. The Fiat manual and possibly the Haynes will show how to adjust it.

Haynes says "undercharging may become apparent as a flat battery" I dont really understand this, Any help?

This means that an under charging generator (putting out low voltage) will become apparent as a battery with a low state of charge.

I'll check the wires etc and if no help I assume the first thing is to get a new regulator. It's not very easy to adjust it home without experience and correct tools!?

If you follow the manual on adjusting you should be able to do it yourself. It is not complicated and you will only need simple tools. If you want you can change to a solid state all electronic voltage regulator. This is what I would do instead of putting back in a mechanical voltage regulator (1950's technology). Hooks up the same as the mechanical unit. Much more reliable and consistent. The voltage regulator you had in your link is an electronic type, not the original mechanical type. I would use the electronic type.

But, should I resolve this first before fitting the 123 ignition, can it be damaged?

I can't answer this as I do not have any experience with this unit. However, I do not think that low voltage would harm the unit.

John

 

[Bambino]

Jake,

This is my earth (ground) strap - it's the flat copper-coloured braid that connects, in this case, the alternator to the car chassis.

Because it is theoretically possible for static charges to build up in the metal components of the car, with the risk of sparking and possibly fire, it is common to fix an earth strap from the engine to the chassis. Mostly this strap runs from the gearbox bell housing to the chassis but it can be anywhere and it usually takes the form of a broad, very low resistance braid rather than a wire.

As to the 123ignition, the unit takes its voltage from the switched supply (+ve coil lead) and should not be worried by a lowish voltage - they have a nominal operating range of 4.0 to 15.0 volts. They are built well and are physically and electrically tough, but if you are concerned then by all means get the engine running (and charging) normally using the points ignition then swap over.

Chris

 

[JakeF]

pics

 

[JakeF]

Like Chris said in the other post

Early cars (engine numbers up to 056195) were fitted with 180W generators with later ones fitted with 230W units.

If I go with the electronic regulator, do I need to worry about these power numbers. Or does it work with both?
This one: http://www.fiat500ricambi.com/fiat500/Dynamo+and+starter/MO1027

 

[jjacob]

Hi Jake,

Voltage regulator is looking at voltage not watts or amps.

Watts = volts x amps

Generators and alternators are usually rated in amps.

12 volts x 19 amps = 230 watts

So you can see why it is critical that the charging system is perfect. 20 amps is pretty low. Modern cars have alternators that put out anywhere from 80 - 150 amps to power all of the modern electrics.
John

 

[JakeF]

Too long time from my engineering studies .
New electric regulator 35€ at fiatricambi.

I fired her up today. Starts well...but. Some problem with running, sputters some time, maybe 1 time in 20-30seconds? Sounds like ignitoin fail?
Runs well at higher rpm maybe +3000rpm. I have a video about the runnig, will add it later.

-Ignition strobed and point gap ok.
-Can a faulty generator or regulator cause this?

During the rebuild I dismantled the distributor and changed the gasket, fitted back to same position. Sound weird because I strobed it, just like it missfires at time.
I try tomorrow with the 123 ignition if I have time.
Then I only have the generator light problem . I will also take some electrical measurement tomorrow from the generator and battery.
The generator does not warm and either does the regulator.

 

[jjacob]

Misfires can be caused by:

Spark plugs: gap incorrect, plugs not the right heat range, or fouled.
Spark plug wires: Can arc between two wires. Are the wires new?
Distributor cap: Carbon tracking can develop inside or outside the cap. Is the cap and rotor new?
Incorrect timing: Have you checked the maximum advance? Should be 18 degrees at 3000+ rpm.
Incorrect dwell (point gap): Did you just measure the distance, or did you use a dwell meter to read the angle?
Points condition: are they new or old. Pitted points can cause erratic dwell or incorrect gap adjustments.
John

 

[Bambino]

I like the reminder on the engine rocker cover in the photo - 'Senza Olio'. It's the sort of thing I'd do

Chris

 

[usafstud]

Too long time from my engineering studies .
New electric regulator 35€ at fiatricambi.

I fired her up today. Starts well...but. Some problem with running, sputters some time, maybe 1 time in 20-30seconds? Sounds like ignitoin fail?
Runs well at higher rpm maybe +3000rpm. I have a video about the runnig, will add it later.

-Ignition strobed and point gap ok.
-Can a faulty generator or regulator cause this?

During the rebuild I dismantled the distributor and changed the gasket, fitted back to same position. Sound weird because I strobed it, just like it missfires at time.
I try tomorrow with the 123 ignition if I have time.
Then I only have the generator light problem . I will also take some electrical measurement tomorrow from the generator and battery.
The generator does not warm and either does the regulator.

The occasional misfire, is it only one or several sputter? I noticed my sputters once every 30 seconds once the car has been warmed up. I thought this was normal or due to my carb needing a rebuild, which I'll have to do in the next week or so. My 500L is all stock carb and ignition.

Let me know what you find out.

 

[JakeF]

Misfires can be caused by:

Spark plugs: gap incorrect, plugs not the right heat range, or fouled.
Spark plug wires: Can arc between two wires. Are the wires new?
Distributor cap: Carbon tracking can develop inside or outside the cap. Is the cap and rotor new?
Incorrect timing: Have you checked the maximum advance? Should be 18 degrees at 3000+ rpm.
Incorrect dwell (point gap): Did you just measure the distance, or did you use a dwell meter to read the angle?
Points condition: are they new or old. Pitted points can cause erratic dwell or incorrect gap adjustments.
John

Spark plugs: Quite new
Spark plug wires: New
Distributor cap: New both
Incorrect dwell (point gap): If you mean the gap between the points, measured with feeler, as normally?
Points condition: Almost new no pitting etc.
Valves are also measured

Before the rebuild I had now probs with runnig or the gen. light. And made everything just like before. So something have went wrong or broken etc.
It sounds just like the ignition is cutting a while, compare to a cut out buttom(stop buttom) which is example in old mopeds. Earth problem or? Can this be a fuel probleml, carb? I think a bad connection from the ignition switch to coil can cause this? Need to control this also and maybe a good idea to take straight a wire from the battery + to the coil. This shows if there is a bad connection in the ignition wire or switch, right?

The ignition coil is new. Check the video!

http://imageshack.us/clip/my-videos/41/najqnuexhvrfwocatrzjwu.mp4/


Thanks all for your help, most to John and Chris!

 

[JakeF]

The occasional misfire, is it only one or several sputter? I noticed my sputters once every 30 seconds once the car has been warmed up. I thought this was normal or due to my carb needing a rebuild, which I'll have to do in the next week or so. My 500L is all stock carb and ignition.

Let me know what you find out.

Actually it is several misfires as in the video. I would vote for the ignition

 

[jjacob]

Jake,

At little hard to tell from the video, but it seems that the engine sputters when the generator light comes on. Is this true? If so, then the voltage is dropping below the level necessary for the coil to fire the plugs with enough energy for a good spark.
It could also be any of the following:
1) a bad coil
2) the wiring to the coil (small wires) and distributor have cracked insulation. Check these wires and also where they enter the distributor for cracks.
3) Bad condenser on the distributor. Did you replace the condenser also?

Try raising the idle speed until the generator light goes off and stays off. If the car does not miss any more, then I think you found the problem.

It could be fuel also. The engine could be flooding or running lean every so often because of a blocked jet or float level that is wrong. Did you rebuild the carburetor and reset the float level?
John

 

[JakeF]

Running problem solved. It was the mixture of the fuel. First I fitted the 123 ignition, still spluttering. Then I started to tune the mixture, thank god . Did not realize it is so sense about the mixture screw, small changes in the screw affects to the running! Fitting 123 was very easy, took 10 minutes . Great starting and very stabile idling!

The generator light is still on. Measured with Haynes guide the generator. Putted a wire between the two points(bolts) on the generator and took the measurement from centre of the wire. It showed 0,86-0,9 V?
At idle speed the battery gave 12V and at higher rpm(maybe 4000-4500) 14,7V. What do you say about these. What causes the light, genarator or regulator?
When one problem solve another is appearing . There were small mount of oil on the floor, maybe behind the flywheel, haha . Maybe ill take the engine off for once when I return from Miami on late january . The seal I used was black, I dont know if it should have been a corteco one?

 

[jjacob]

Great to see you fixed your problem.

You may wish to replace your voltage regulator with a new one, or try to adjust it yourself. 14.7 volts at 4000 rpm is actually a little high, but shows the generator is putting out voltage. It sounds like maybe the cut-in speed for the voltage regulator needs to be adjusted.
Since an electronic voltage regulator is only 35 euros I would just replace it.
If your battery is more than 4 years old, you should replace that also.
John

 

[JakeF]

Yeah, it was a nice to hear her runnig smoothly. I emailed fiatricabmi and asked about the regulator and they updated the info about it on their website. Great service!

Thanks again for help.