Hello,
I have a Fiat 500 twinair 80 hp from 2014. What a delightful car to drive with a big personality. We have had it for about one year now with no problems. A month ago it began to leave traces on the driveway, at first it looked like af oil leakage but it was a bit to thin consistancy. A white tray showed red cooler fluid - oh no!
It came from the back of the engine, dripping down onto the exhaust pipe. It was really hard to see from underneath because the starter motor was in the way. Some mornings there was a big pool, and other days just a few drops. It dripped much faster when the car was started and warm. It consumed about 100 ml every two days over the last few weeks and was accelerating in rate, so I needed to top it off every other day. Luckily, there were no signs of coolant in the oil.
There were no signs of leakage from the thermostat housing or the hoses. It was actively dripping when the car was turned off, and since it came from behind the engine, I concluded it had to be from the oil cooler gasket. It wasn’t that expensive, so I ordered a gasket a few weeks ago.
Yesterday, I finally took on the beast. I only have the German repair manual "Reparaturanleitung Handbuch – Fiat 500 der Baureihe 312 – Baujahre 2007 bis 2019"—a pretty solid guide with a lot of interesting info on the UniAir module. However, it doesn’t cover much about replacing the oil cooler, and my German isn’t great.
From my experience, here’s what you need to do to change the oil cooler:
The oil cooler is held in place with five bolts. The alternator has three bolts, and the starter motor also has three. To remove the oil cooler, you must remove the alternator—one of the oil cooler bolts sits directly underneath the plastic part of the alternator housing. It’s impossible to pull out that last oil cooler bolt while the alternator is still mounted. See the two pictures below for a top and bottom view of the problematic bolt.
Maybe you could get away with just removing the plastic part of the alternator, but I couldn’t figure it out with the limited space available—so I ended up removing the whole unit instead. You’ll need to take off the accessory belt, which was actually harder than I expected. Even with the belt tensioner fully “relaxed,” the belt was insanely tight. Reinstalling it was even worse. Just replace it while you’ve got it off anyway.
On my car, the alternator was secured with three 13mm bolts—two on the bottom, and one wedged between the alternator and the A/C compressor. You’ll need to remove that third bolt blind unless you want to take off the aircon compressor (I didn’t).
As for the starter motor, mine was held on with three T50 Torx bolts. The first two are easily visible from underneath, but the third one is tricky—it’s up top, against the engine. I used a lot of extensions and went in through the wheel well. Just note this method only works if the alternator is already removed.
That said, removing the starter motor is probaly not necessary if you're only replacing the oil cooler.
The oil cooler itself is held in place by five 13mm bolts. I removed them from the top without too much trouble—space is very tight, but the bolts weren’t overly torqued.
As you can see in the pictures, the plastic is cracked, and the gasket is also damaged—it looks like it tried to escape its torment. I suspect this happened because the previous gasket was too large. I really can’t see how this kind of damage could occur with a properly sized one. When I compared it to my new gasket kit, the old one was clearly oversized.
I repaired the cracked plastic with epoxy glue and installed a new gasket. If it leaks again, the whole assembly will need to be replaced entirely. I drove around for a few hours today and haven’t seen any signs of leakage so far fingers crossed. If i were in this position again i would just have bought a whole new oil cooler assembly from the beginning.
I have a Fiat 500 twinair 80 hp from 2014. What a delightful car to drive with a big personality. We have had it for about one year now with no problems. A month ago it began to leave traces on the driveway, at first it looked like af oil leakage but it was a bit to thin consistancy. A white tray showed red cooler fluid - oh no!
It came from the back of the engine, dripping down onto the exhaust pipe. It was really hard to see from underneath because the starter motor was in the way. Some mornings there was a big pool, and other days just a few drops. It dripped much faster when the car was started and warm. It consumed about 100 ml every two days over the last few weeks and was accelerating in rate, so I needed to top it off every other day. Luckily, there were no signs of coolant in the oil.
There were no signs of leakage from the thermostat housing or the hoses. It was actively dripping when the car was turned off, and since it came from behind the engine, I concluded it had to be from the oil cooler gasket. It wasn’t that expensive, so I ordered a gasket a few weeks ago.
Yesterday, I finally took on the beast. I only have the German repair manual "Reparaturanleitung Handbuch – Fiat 500 der Baureihe 312 – Baujahre 2007 bis 2019"—a pretty solid guide with a lot of interesting info on the UniAir module. However, it doesn’t cover much about replacing the oil cooler, and my German isn’t great.
From my experience, here’s what you need to do to change the oil cooler:
- Have thin arms – I don't
- Remove the two plastic covers for the wipers and washer system so you can work from above.
- Remove the battery, battery tray, and with that, the ECU.
- Remove the alternator.
- To remove the alternator, it’s easiest to take off the wheel and wheel well to get the accessory belt off. Just replace the belt while you're at it—that son of a b*** is tight.
- (Optional) Remove the starter motor – sometimes it’s necessary to confirm the oil cooler is leaking. I removed it, but I’d probably try leaving it on if I did this again.
- (Optional) Have a lift. I didn’t... but I also hate myself.
- Drain the coolant. My car did not have a drain plug on the radiator?! Why Fiat?!
- Drain the oil - remember the right type when filling it up again. I used Selenia Digitek Pure Energy 0W-30.
The oil cooler is held in place with five bolts. The alternator has three bolts, and the starter motor also has three. To remove the oil cooler, you must remove the alternator—one of the oil cooler bolts sits directly underneath the plastic part of the alternator housing. It’s impossible to pull out that last oil cooler bolt while the alternator is still mounted. See the two pictures below for a top and bottom view of the problematic bolt.
Maybe you could get away with just removing the plastic part of the alternator, but I couldn’t figure it out with the limited space available—so I ended up removing the whole unit instead. You’ll need to take off the accessory belt, which was actually harder than I expected. Even with the belt tensioner fully “relaxed,” the belt was insanely tight. Reinstalling it was even worse. Just replace it while you’ve got it off anyway.
On my car, the alternator was secured with three 13mm bolts—two on the bottom, and one wedged between the alternator and the A/C compressor. You’ll need to remove that third bolt blind unless you want to take off the aircon compressor (I didn’t).
As for the starter motor, mine was held on with three T50 Torx bolts. The first two are easily visible from underneath, but the third one is tricky—it’s up top, against the engine. I used a lot of extensions and went in through the wheel well. Just note this method only works if the alternator is already removed.
That said, removing the starter motor is probaly not necessary if you're only replacing the oil cooler.
The oil cooler itself is held in place by five 13mm bolts. I removed them from the top without too much trouble—space is very tight, but the bolts weren’t overly torqued.
As you can see in the pictures, the plastic is cracked, and the gasket is also damaged—it looks like it tried to escape its torment. I suspect this happened because the previous gasket was too large. I really can’t see how this kind of damage could occur with a properly sized one. When I compared it to my new gasket kit, the old one was clearly oversized.
I repaired the cracked plastic with epoxy glue and installed a new gasket. If it leaks again, the whole assembly will need to be replaced entirely. I drove around for a few hours today and haven’t seen any signs of leakage so far fingers crossed. If i were in this position again i would just have bought a whole new oil cooler assembly from the beginning.
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