Hey everyone - rookie to the forum.
Here is the issue. New to me 69...driving it yesterday around 55mph. Start getting a really shxxty noise coming from the motor. I drop speed to 35 to get off the freeway. Finally off the freeway I pull into a parking lot - leave motor running so I can see if there is anything obvious - 20 seconds in the motor stops and thats all she wrote. Sounds like it froze up. Try to refire it and it sounds really really bad and sounds the the motor is just dragging. Had it towed home.

Today I go out to see what is up with it - and i don't know a thing about these motors....find my way to the starter cable on the back of the motor and try cranking it over. Same thing. So, I pull the plugs to release compression and try it again. This time the motor is spinning easier and the same noise I heard on the freeway came back. I notice the generator is locked solid and the belt is just slipping...which is the noise I heard on the freeway.

I pull off the belt and the motor spins as it should with no funky noises...So i figure I would see if it will fire without the generator so I can at least feel better about the motor not being trashed. Wont start. Check for spark - no spark...

So - thats the store - here are the questions...
1) Will these fire with battery only power? Or does it need the power coming from the generator to create spark? - which is why I'm not getting spark now...

2) Assuming its actually a locked up generator and not an issue with the fan - where in the US can I get a generator?

3) Remember Im a rookie - how does the gen come out? I see 4 bolts that are holding the gen bracket to the motor. Do i remove all of these? or is there a way to relieve the tension on the clamp around the gen? if so - how?

4) looks like after that is pulled off I just yank out the cooling cowling and get to work on this yeah?

thanks for the help

Hi and welcome.

Is it a dynamo or alternator? Just in case dynamo is usually black and has a clamp around it that is secured by a bolt that is integral to the clamp with a nut that you tighten up to secure the dynamo in place and as you say has 4 nuts securing it to the block.

In answer to your questions.

1). It should start or get a spark without the generator regardless of whether it is alternator or dynamo, the two circuits are pretty much independent of each other.

2). Luxe in the US commented earlier that it was cheaper for him to get a parts from Europe that order from Mr Fiat in the US and he has also been doing a dynamo rebuild so he should be in a better place to comment.

3). Again depends if it is a dynamo or alternator. As you have discovered 4 bolts on the block and then you have to remove the big air intake at the back of the fan housing and if I recall it is a 17 or 19 mm lock nut on the end of the generator shaft but you have to lock the other end in order to undo it, so you need arms of an octopus to get a socket inside the fan housing where you have removed the air intake pipe and then another one on the flywheel end. Then there should be two 10mm nuts securing it to the fan housing tinware at the front.

4). There is a link on here to a workshop manual. That should help you out. http://docfiat500.free.fr/Pour%20TIBOde%20Fran%E7ois%20qui%20te%20dit%20MERCI/F500_Manual.pdf

You have probably just joined the friendliest forum in the world, so keep asking the questions and there will always be someone to help.

Tony

Thanks for the reply!

It is definitely a generator. It is black and has the clamp around it. Ill look for the bolt that holds it all together. That should prevent me from having to remove the 4 bolts that holds the clamp to the motor.

My thought is it should fire without the generator - have done that for years with non fiats. Although not truly independent of one another as a positive current should run though both, it is possible current doesn't run from the batter straight to the coil and it only runs to the starter motor - maybe?

I ran an inline spark tester again this evening and sure enough - no spark. The only thing that has ben changed in this part of the system, is having the generator in a completely non functioning state. Ill search out the wiring diagram and bet I can run a jumper lead from from the battery to the coil and it should fire.

Ill look and see what is available for generators from overseas. Its $350 from Mr Fiat.

Im stoked on this car. I have tons of Vespa's and Lambretta's. Along with a 70 VW westfalia. I have played around with american hot rods for years and this is my first old school European car. A new challenge.

Hi Airfin. That's a lot of intelligent questions and an equal amount of intelligent answers from Tony the contortionist.

I wouldn't be too hasty in ordering a new dynamo because the chances are that it mainly needs new bearings (and carbon briushes) which is possibly an easier job than actually removing it. I think that removing the rear nut on the impeller might be the biggest challenge as it isn't all that easy even when the engine is out of the car. I found an air wrench was the most reliable way to loosen it.

Have you considered the possibility that you might have "cooked" something? I think this engine will get incredibly hot very quckly without the fan. So if you drove for a few miles with the dynamo seized it might have affected the coil or condenser. There is even the possibility that you might now have sticking valve or other mechanical trauma that it stopping the engine from running.

The original wiring to the coil is a thin, pale blue wire which comes from the ignition without any interaction with the starter, so you can easily check at the coil if the wire on the + terminal is getting a decent current.

You're correct that the engine will work without the dynamo or fan connected when all things are setup correctly, but if you get it going I wouldn't go for a drive and don't leave it running for long in any case.

Keep us posted please and PHOTOS!

Here is a pic just before I bought it.

I've considered something fried when all this happened. I'm sure it got warmer than it should and I originally thought i seized the motor. The reason right now it won't fire is definitely a lack of spark. I'll try to run elec test tomorrow or Friday. I definitely am not going to drive it , I just wanted to see if the frozen generator is the only issue to resolve. Can't be a hard fix.

And because we like pics...

Hi Airfin have a read through this thread from a few weeks ago. It has some posts by myself and others that detail how the 12v gets to the coil.

https://www.fiatforum.com/newbie-central/446109-starting-problems-fiat-500f-7.html

First off where are you located in the States? You have all the advice that you need regarding the generator. You will find that the coil and condenser are quite finicky. Like stated getting the nut off the shaft at the fan end is tricky; I used a screw driver on the pulley end and managed to get it wedged on one of the 10mm nuts and blocked on the engine mount to create resistance.


Once you loosen the bolt on the underside of the black band and loosen the two 10mm nuts on the cowling, the dynamo will come out with ease. Do be careful when removing the dynamo as there is a small woodruff key on the shaft where the fan mounts. Dropping that in the engine cowling is a b*tch, trust me.


I would recommend since you already have the dynamo out, you might as well loosen the 4 nuts that hold the dynamo bracket to the engine to inspect the integrity of the bracket. Mine was broken in two places and was a time bomb waiting to happen.


You can get a rebuilt dynamo here: https://www.fiat500vdlaan.nl/en/webshop.php?CategoryID=9 , but I would recommend you pull it apart and inspect it yourself. More than likely one of the two bearings is seized. Again you can get those at the same place as I posted. Do not get them from Mr. fiat as one of them does not contain a dust boot to keep crud out. Replacing the bearing on the can end of the dynamo will require you to drill out three aluminum rivets to pull the face plate apart. I sourced three stainless steel bolts and fastened the face plate back together, ground off the excess bolt, and mushroomed the bolt end to keep the nuts from coming off.


When you order from Van Der Laan, tell them you do not need registered mail and shipping will be half price. He does business via paypal.


Like stated keep the engine running as little as possible without and dynamo/fan turning. These engines get hot quick.

Your generator might be able to be rebuilt. I would remove it from the car and take it to a local shop that rebuilds generators and alternators. You might have to buy the brush set, but they should be able to do everything else. They will tell you if the generator is rebuildable. This will be cheaper than buying another generator. You are also going to need a new generator belt.
Mr. Fiat is very expensive. They would be best for the brush set and belt but if you need a new generator you can get parts from Europe in a few days a lot cheaper. My order from FD Ricambi https://www.fiat500ricambi.com/ arrived in just a few days. Make sure you register on the site as VAT (Value Added Tax) is then removed and the part will be 20% cheaper for us in the USA.
At the same time you might as well order a new coil.

Make sure the battery is fully charged. If the generator seized then you were driving only on the battery.
I am in the Nashville, Tennessee area
John

Thank you for ALL the help everyone.

A quick update -

Wouldn't fire because the points were sticking. Fired right up and motor sounds good.

Time to pull the generator - I am in the SF Bay Area and a shop close to me is going to rebuild the generator. Few days and Ill be back on the road.

Stoked in all this its a small amount of money and larger inconvenience vs a ton of money and lots of irritation.

Well, in the mean time you could pop the top cover of the engine cowling and look straight down at the fan if you are bored. This will give you a good idea of how gunky the inside is and the fan as well. Mine needed a good amount of cleaning so I had to crack the bottom of the case open to let all the gunk drop out as I used engine de-greaser. Food for thought!

Airfin said:

Thank you for ALL the help everyone.

A quick update -

Wouldn't fire because the points were sticking. Fired right up and motor sounds good.

Time to pull the generator - I am in the SF Bay Area and a shop close to me is going to rebuild the generator. Few days and Ill be back on the road.

Stoked in all this its a small amount of money and larger inconvenience vs a ton of money and lots of irritation.

Click to expand...

It’s been a while for this one but if you’re still on, can you tell me how much the generator rebuild cost and if you had to replace brushes or just recondition the existing ones? Does anybody know how many brushes there are if I wanted to order them in advance?