This is a continuation of the posts I started in the Panda section "what shared the drive with your Panda" which started with Becky, our Panda, and led on to being about my son's Punto which he's left with me whilst he's on his happy hols.

If you'd like to read the posts in the Panda section you can catch up with what I've done so far. Having completed the service work, there's still outstanding the poor clutch action, leaking gearbox selector shaft seal and cooling fan slow speed not working. The rusty sump (not leaking yet) and rusty front pipe are going to have to wait.

Air con versions have a two speed radiator cooling fan which you can drive using the "actuators" function in MES (Multiecuscan). When I did this I found the fan ran at full speed but not at the slower speed. It achieves the slower speed by switching the current through a resistor I could hear the relay clicking inside the under bonnet fuse box (N/S) so suspected it might be the resistor pack which had croaked. (my experience of resistor packs is that they do tend to burn out after a while - the one on the heater fan is particularly prone to it if you perpetually drive around with the heater fan on slow speeds.) I unplugged the connector at the resistor, it's a simple 2 wire job, so the current comes in on one wire, through the resistor and out to the motor on the other wire. Setting my multimeter to DC volts (20 volt setting on mine) I plugged one lead into one of the plug connections and the other into the other. So now the multimeter is taking the place of the resistor. If the rest of the circuit is OK I should see battery voltage on the meter when I activate the relay with MES. Yippee! that's exactly what happens so the relay is probably ok. I say probably because the voltmeter is passing virtually no current at all so is not really putting the contacts in the relay to any meaningful test. I could have bridged the relay plug with a bit of wire in which case I would expect the fan to run when triggered. I removed the resistor pack and this is what I found:

The male connector terminals and the plug were in good order with no signs of corrosion.



However the circuitry - which you can't see when the resistor is installed in the radiator shroud, just under the coolant expansion tank - was badly corroded and doing a continuity check on the terminals (Ohms scale on Multimeter) showed it to be open circuit.



Also there were some signs of the coil itself being "distressed"



So, new resistor pack needed - anyone know where I can get a good quality one cheaply?

Then I started thinking seriously about this clutch problem. The clutch itself bites well and doesn't slip. No "funny" noises either (as in release bearing, screeching lining, etc) it's just that the pedal is about two thirds of the way to the floor before it frees and conversely it bites almost as soon as you start to lift the pedal. It's exactly like there's air in the system - even feels a little on the spongy side. I've bled it comprehensively using at least half a litre of fluid and it's made absolutely no detectable difference! I'm thinking master cylinder? DaveMcT has suggested this also. Expensive to be mistaken though with a cylinder at local factor being over £60 and even on line still around £50. As I'm sitting here it's just occurred to me that the mechanism - master and slave cylinder, actuating arm, swivel, release fork and bearing is pretty much identical to our Panda. Tomorrow I'm going to measure the distance the actuating arm moves on the Panda over a full stroke of the pedal and compare it with the Punto. I suspect I'm going to find that the Punto will not be moving anything like as much. If so I will feel much more confident to buy that M/Cylinder.

First job in the morning though will be to strip out the gear selector and renew that leaky seal. Would have done it today but the weather was not at it's best. Tomorrow looks much better. Still feeling a little nervous about tackling this as it's the first Fiat gearbox I've ever actually taken "bits" to pieces on.

Pugglt Auld Jock said:

As I'm sitting here it's just occurred to me that the mechanism - master and slave cylinder, actuating arm, swivel, release fork and bearing is pretty much identical to our Panda. Tomorrow I'm going to measure the distance the actuating arm moves on the Panda over a full stroke of the pedal and compare it with the Punto. I suspect I'm going to find that the Punto will not be moving anything like as much. If so I will feel much more confident to buy that M/Cylinder.

First job in the morning though will be to strip out the gear selector and renew that leaky seal. Would have done it today but the weather was not at it's best. Tomorrow looks much better. Still feeling a little nervous about tackling this as it's the first Fiat gearbox I've ever actually taken "bits" to pieces on.

Click to expand...

Mrs J kindly agreed to pedal push for me so the first job of the day was to compare the clutch release arm movement on the Punto with the Panda. They are very similar in design and, more to the point, of roughly the same length, so you might expect them to move by similar amounts. The Panda lever moves almost as soon as the pedal starts to descend. The Punto pedal is half way to the floor before even the slightest movement is seen. The Panda arm moves about twice as much as the Punto. Must be the master cylinder?

Having dealt with that Mrs J went indoors to put a wash in as the weather was nice and sunny. I started on the Punto gear selector seal by wiring my big jump battery to the Punto battery terminals and disconnecting and removing the Punto battery which I put to charge on my Ctek. Then I pretty much just followed the guide in the Grande section.

The bolt to which the earth cable is secured was quite "stiff" to remove but the others came out cleanly. Once out the electrolytic corrosion on this one bolt was quite clear to see and there was some corrosion on the screw threads:



They all cleaned up nicely with a bit of fine emery cloth, a wire brush and a thread clean with a die.





Having looked very carefully at Jarmot's guide I was worried that one, or both, of the hollow dowels might fall into the box as I removed the top. I need not have worried, they were both tight in the casing I was removing. You can probably see them here.



Then, after a good clean down, I got stuck into removing the selector shaft it'self. The roll pin was really tight - put a bit of a mushroom head on my punch getting it out. It does just punch straight through into the inside of the housing and all you need to do to recover it is to invert the housing and it falls out. I'm very grateful to Jarmot for telling us about the circlip which "hides" under that plastic bush. Easy enough, once you know it's there, to remove it with a couple of screwdrivers.

If you twist the main selector shaft it "clicks" into a detent position. So this tells me there is a spring loaded detent ball (or similar) under it. I've done boxes in the past that, when you remove a shaft like this, small ball bearing "detents" fire off across the workshop at great velocity! So I covered the housing with a big heavy cloth as I withdrew the main selector shaft. Cautiously removing the cloth reveals the selector fork just sitting there - Here it is after removal sitting on the worktop



The detent ball is sensibly retained in the housing so you dont need to worry about loosing it - Well done Fiat!



The old seal came out under firm persuasion from my big screwdriver and it was nice to see no perceptible wear on the bushing (which seems to be coated in a white plasticy material - Teflon or similar?) The old BMC gearchanges used to wear their housings/bushings to such an extent that no number of new seals could overcome the leak caused by the shaft slopping about and I had wondered if the same was going to be the case here.



The new seal is a reddish brown colour whereas the old one was black. I've noticed a lot of seals seem to be this colour now, probably an improved material?



Anyway the new seal went in very nicely under the persuasion of a socket of suitable diameter and a 1 lb ball pein hammer.



Threading the shaft back in, copiously lubricated with fresh gear oil, is aided by the fact that it has a chamfer on the large diameter so that it slips easily into the new seal without damaging it. Again, well done Fiat!



The new roll pin I'd bought took some determined persuasion to start of in it's hole but once it realized I wasn't giving up it suddenly just slipped in. The circlip was easily slid back onto the shaft and all was ready for reassembly. I had previously cleaned up the old gasket cement so now just needed to degrease the mating faces before applying sealant and reassembling. I know I'm always interested in what other people use for sealant so I can tell you I've been using Loctite SI 5980 for quite some time now with excellent results. Halfords, where I buy, sell it at a reasonable price and they even give discount if you have a trade card.

https://www.halfords.com/workshop-t...xhaust-repairs/loctite-si-5980-flange-sealant

So that's about it. Carefully - so as not to "catch" sealant on anything - lowered the housing back onto the gearbox casing and tightened everything up.



Looks lovely doesn't it? and all the gears are selecting too - which always helps!

The Punto's own battery was by now showing a nice green light on the charger so I gave it a nice clean up and reinstalled it then removed the "saver" leads from the jump battery. Tried the radio and , Yippee! it's still working.

There you are then. I was feeling a little nervous about doing this just, I suppose, because it was a wee bit leap into the unknown. It turned out to be very straightforward and I think any competent DIY mechanic with a reasonable selection of tools could expect to be successful. At the end of the day our local indy quoted a likely time of 2 hours plus parts @ £45 per hour. I bought the seal and roll pin from the main dealer for £8.96p. Result I'd say?

Regards to you all
Jock
Oh, by the way, it took me nearly 3 hours working at a very relaxed and careful pace. Could probably do the next one (Panda maybe at some time?) in around 2 or maybe a wee bit less. Also check that breather on the top of the casing. mine was nice and unobstructed but a blocked breather could well be why you've got the leak in the first place - and, give that earth point a clean up too.