1973 850 spider No Spark

Smajeski

Low Mileage
Good Day,
I recently inherited a 1973 Fiat 850 Spider Sport with 53K original miles. The former owners weren't mechanical at all but always had the car serviced by a Fiat garage in California so I know it's not been abused. My issue is that the car was placed in storage in 1996, luckily drained of it's fuel and coolant before, and it was supposedly not running well. I have a feeling that time has been this little car's worst enemy. Here's what I've replaced or repaired so far.

1. new weber 32 ich carb. Original carb was completely shot and not worth rebuilding.
2. ignition coil - Stock Magneti Marelli
3. spark plugs - NGK
4. spark plug wires - Magneti Marelli
5. distributor cap, rotor, points, condenser - Magneti Marelli
6. electric fuel pump - Midwest Bayless suggested
7. new belts - both
8. new oil, cleaned the filter out.
9. new battery

Tested the car after each new item and no change. It's getting fuel but no spark. Is there an ignition relay or another piece that I'm missing in the loop? All the wiring looks sound, no mice chews, no breaks. I've redone the wiring on the parts close to what I've changed just to keep things new and less brittle. Just can't figure out what I'm missing to get this little pink car running. Any ideas? Thanks in advance. A few before and after photos in case you can spot something I'm missing.

Steve
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What does your dwell meter indicate?
Have you checked for spark on the coil wire?
Is the Ballast resistor wired correctly?
 
The ballast resistor isn’t needed as the coil is adjusted to be stock voltage, at least that’s what I’ve been told and sold.
I have no idea what a dwell meter is or where I would check it.
I haven’t check the spark in the ignition wire, it’ll be the first thing I do in the morning though. Totally makes sense to see where the break is. Thanks dnudlman
 
Okay, so I’m not completely a dork. Went and checked dwell meter. The points are set at 44mm per spec but I just read that you have to check the dwell by turning the car over. Why would that change the distance of the points from the distributor? Forgive me… all my cars have had computers for this kind of issue. I’m having to learn new tricks here. Thanks again for the help.
 
Oh boy, do I have experience with no spark. Check the spark at the ignition wire first. Just curious though….are all of the other electrics working? Gauges seem happy? Lights and all work? At one point I had no spark because a wire had fallen off my ignition switch. All kinds of fun to be had with an 850! Nice looking car too!
 
Okay, so I’m not completely a dork. Went and checked dwell meter. The points are set at 44mm per spec but I just read that you have to check the dwell by turning the car over. Why would that change the distance of the points from the distributor? Forgive me… all my cars have had computers for this kind of issue. I’m having to learn new tricks here. Thanks again for the help.
Actually dwell is measured in degrees the points are open or closed, don't recall which. The reason is dwell is measured electrically, not physically. If no dwell, points system not working. Its also more accurate than ONLY setting the points with a feeler gauge.
 
Everything else seems to work. Lights and such. Thanks Daniel, it is a cool little car. My godmother is a cool gal, fit her personality perfectly. Trying to do it up right and make her proud.

dnudlman, thanks for the idea. I’ll have to YT some videos on points and dwell. I’ll also check the spark between coil and cap. I just picked up a tester so it should be easy to see if it’s that. Learning all sorts of patience with this car.
 
I don’t think so. When I turn the key to on, without cranking , the coil shows no voltage. Does it have to go to crank to send the power to the coil?
 
Sorry, it's been a long time since I've had to do anything but simple DIY type work on my cars. This car is the same age as me and may be in better shape after all the hair I've lost trying to make it run. Thanks for the help guys.
 
Okay, I was wrong about the ignition coil. I turned the key on, took the disto cap off and tested the coil line for power. It's showing around 9v+- so I'm getting power to the cap but not to the plugs. All the parts on the distributor are new, cap, rotor, points, condenser..... The points are adjusted to 44mm per spec. The distributor is turning so I know that isn't busted (had an old Ford EXP that blew the distributor shaft into pieces, that was fun). Any ideas?
 

Smajeski,​

Witnessing spark to he plug. Are all of your plugs removed from the head and your witness plug well grounded ?

Petronix is a great alternative to he mechanical breaker point setup....but with that said.....In the distibutor....Do you have proper stackup of the connecting stud and the insulative wafer washers ? You had mentioned that you swapped out all of the distributor components. The insulative washer in the correct location/position ?
 
Okay, I was wrong about the ignition coil. I turned the key on, took the disto cap off and tested the coil line for power. It's showing around 9v+- so I'm getting power to the cap but not to the plugs. All the parts on the distributor are new, cap, rotor, points, condenser..... The points are adjusted to 44mm per spec. The distributor is turning so I know that isn't busted (had an old Ford EXP that blew the distributor shaft into pieces, that was fun). Any ideas?
should be 12v at the coil with the ignition key on, not cranking. Distributor cap on or off, should not matter.
 
this could be helpful, you would need a multimeter that measures resistance OHMS.

here is what I use, if you don't have one, get one, you will use it over and over again

this youtube channel has good fiat 850 vids
 
Some more thoughts
Do you have a remote crank switch tool? https://smile.amazon.com/Performanc...670124160&sprefix=remote+crank,aps,155&sr=8-7

I would test spark but disconnecting the heavy ignition wire from the cap, this wire goes to the center of the coil. I would hold it with an insulated pliers and hold it about 1/4 inch from a ground (engine block is good). If you have an electric fuel pump, disconnect it. Using the remote switch crank the engine and look for a spark against the ground.

If you can see a spark, then you are getting spark to the cap. Next determine if your distributor is correctly manually timed. If the rotor is not pointing to #1 on the cap when the engine is a TDC, then when the points fire, the ignition pulse is not going to the plug.

The procedure to correct this is in the manual.

Looking at your photo, I'd bet your distributor position is off about 45 degrees.
 
Here is my motor. See the position of the distributor (marelli)
1. You are missing the carb drip tray. You really need this unless you want gas dripping on to your starter motor. Might turn your pink car into BURNT Orange.
2. You need the chrome turtle back air cleaner, black crinkle paint on the valve cover and the ABARTH oil cap. All worth additional 25 HP.
 

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dnudelman

Howdy! I noticed his weak voltage also....but still should be enough to excite the coil. Is the supplied voltage to the correct post on the coil ? The cap and rotor.....is there excessive gap? Is the plunger on center of the cap contacting the rotor ? The coil itself....is the resistance measuring within spec ?

This is actually a pretty easy one (smile). All 850 drivers should be armed with the electrical schematic. If he doesn't have one, he should !

Once spark is established at the plug....then the next hurdle is making sure it is being supplied to plug1 at the correct moment (smile)
 
Les, he has all new marelli components. What could go wrong? :p
David,
Au Contraire.......Ducellier 4209A fitted on mine. It took a few to make one good one <wink>

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Carb drip tray mandatory requirement ? Huh ? What has you spooked ?

I've seen many 850's without them, including mine. Where is the errant fuel supposedly leaking from ???

Thanks upfront for any insight on this one.
 
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