General Can i mount a 500 to a syncronized gearbox?

[jtrashy]

1972 Fiat 500 L

I replaced the original motor and gearbox with a 650 / synchronized gearbox from a Fiat 500 R or 126

I'm having motor issues, can I mount my 500 to the newer gearbox? or should I reinstall the 500 and the original gearbox as a unit?

 

[the hobbler]

1972 Fiat 500 L

I replaced the original motor and gearbox with a 650 / synchronized gearbox from a Fiat 500 R or 126

I'm having motor issues, can I mount my 500 to the newer gearbox? or should I reinstall the 500 and the original gearbox as a unit?

The easiest answer to your problem would be to re-fit the 500 engine AND gearbox as a pro-tem measure. However, if you wish to retain the synchro (126) gearbox you will have to fit the 500's bell-housing to the '126' gearbox, along with the 500's starter. This is not a difficult job, but it is a 'gearbox-out' job which can be done in a day(including removing/refitting the gearbox).
What is the problem with your '650' engine? Maybe we can help here on the forum--it is what we are here for.

 

[jtrashy]

Well....really not sure. Metal on metal noise which didn't seem internal. The next startup a few days later, something seemed to stop the engine after a few minutes of warmup.
I moved the motor with a ratchet on the generator, after a few rotations the ratchet violently rebounded back. Not sure if thats related or normal. Dont remember it doing that before when positioning the pistons the same way for adjusting the lifters. But I did have the spark plugs out then.
Any of this make sense?
My plan was to start by removing the fan housing, look around and dig deeper as needed.

 

[the hobbler]

Well....really not sure. Metal on metal noise which didn't seem internal. The next startup a few days later, something seemed to stop the engine after a few minutes of warmup.
I moved the motor with a ratchet on the generator, after a few rotations the ratchet violently rebounded back. Not sure if thats related or normal. Dont remember it doing that before when positioning the pistons the same way for adjusting the lifters. But I did have the spark plugs out then.
Any of this make sense?
My plan was to start by removing the fan housing, look around and dig deeper as needed.

Before you go to the trouble of heaving the engine out Justin, take the top fan-cover off and see if the fan has got fouled up with the other parts of the shrouding. Even with the plugs in, you should be able to rotate the engine WITHOUT it 'bouncing back'. It may be that the fan has come loose and IS the cause of the noise and the engine jamming. Keep us in the picture please. I dropped you a line direct---let me know if I can be of any help with regard to parts found to be required.

 

[jtrashy]

Can’t tell if something is wrong
Well def know the source of The noise, fan blades are totally gone. Any ideas why this happened? ALL bolts/nuts were tight. Dyno seems intact with no weird noises when I spin it.
Ordering fan tonight.
Any other concerns I should assess before I get it back together?

 

[StMarks]

Any ideas why this happened?

Looking at the damage, it suggests that the stakes holding one of the impellers had failed at some point, and that once that impeller had released itself into the casing it would have presumably made short work of the rest of the fan.?

As for the cause ??????

However fwiw I have learned a valuable lesson from your misfortune, and shall be carefully inspecting the fan & all it's impellers when I reach that stage of my own ongoing 500/650 conversion.

 

[fiat500]

I had one where the tabs that secure the blades became loose because of being corroded and then cleaned of rust, but yours looks new. They are finely balanced, and it would take very little to upset that balance; as said before me, maybe just a small part failed and took out the rest, or there might have been a tool or a fastening that was left in the housing during assembly or fell in later.

I was advised on the forum that a stronger, fully welded version of the standard impeller is available.

 

[the hobbler]

I had one where the tabs that secure the blades became loose because of being corroded and then cleaned of rust, but yours looks new. They are finely balanced, and it would take very little to upset that balance; as said before me, maybe just a small part failed and took out the rest, or there might have been a tool or a fastening that was left in the housing during assembly or fell in later.

I was advised on the forum that a stronger, fully welded version of the standard impeller is available.

You are correct Peter---various (sadly, mainly on the Continent) suppliers do sell fans which are marketed as "welded and balanced" I have such a fan in the "695SS" engine that I am in the throes of building, and yes, the 'blade-to-shell' tabs are all welded, as against the standard fans where the tabs are just twisted to lock them in place. I had given thought to fitting one of the aluminium fans, but having purchased one, I was very dissapointed in the quality of the casting and the finish on it--a lot of lumps and "casting flash". I was also not totally convinced that the smaller diameter of the aluminium fan (as against the steel fans) would pump as much air across the engine. In the end I sold the aluminium fan and fitted one of the "welded and balanced" variety.