Top change gearbox, gear selection issue

I've finally completed my bottom change to UT top change gearbox conversion in my 70SX (with 1500 X19 engine). There are quite a number of parts needed for the conversion, and my original estimate of one day to do the change over actually took nearly three days. Still, all is now in place and the new 'box is much, MUCH quieter. I believe the original 70SX bottom change 'box must have been a few hundred miles away from exploding on me...  

Only issue I have is that the gear change is not brilliant as it's hard to get into gear, especially 1st and 2nd. It doesn't graunch like a poorly adjusted clutch, it's more like a lot of resistance is felt when trying to move the gear lever to select a gear. If you used some force and change quickly, it goes in. Slower and more gentle changes are met with a degree of resistance (no graunching noises from the gearbox when doing this, making me suspect a linkage issue). It's slightly better with the engine off than with it running, but not greatly so. I've adjusted the selector rod (only one can be adjusted) and the change is better, but still not perfect. It's worth pointing out that I am using the original 70SX clutch cable, which fits fine and operates like it should.

Is there any particular way that the adjustable selector rod needs to be set? Anything else I should look at to make the gear selection smoother and lighter?

Cheers for any help!

Update: I ran the car with the 'new' top change UT 'box, checked/ topped up the oil and re-adjusted the clutch. The gear change is a bit better, but 1st and 2nd are still not great, especially with the engine running, clutch pressed down and the car at a stand still. Once the car is rolling slightly, 1st and 2nd select a lot better. 3rd, 4th and 5th seem OK most of the time. Reverse nearly always 'graunches' when selected.

The adjustable selector rod between the gear linkage and 'box I believe only adjusts the lateral position on the gear stick in the car. There doesn't look to be anything else that can be adjusted.

Also, I'm running the 'box with 15w 40 semi-synthetic engine oil (apparently it's the same grade as gearbox oil, which is graded differently).

Not sure what to look at next. Maybe the 'box is slightly worn as 1st and 2nd can often be the first gears to give trouble? Anyone have any suggestions? Different grade of oil maybe? Anyone else had similar problems and found a solution?

have you let the gearbox oil warm up? the box in my uno is always a bit stiff from cold but works perfectly once is warmed up

Yup, have given it a good few runs and got it up to temperature Mark. It's 1st and 2nd, and reverse that still have these issues. As mentioned, 1st and 2nd are hard to get into at a standstill, but a lot better if the vehicle is ever so slightly rolling. Reverse always graunches on selection (it's the only gear that does this). Otherwise it seems fine, no noises and no jumping out of gear.

Maybe it's just a little worn? I was told it was a good 'box, but otherwise have no idea of its history and mileage. For now it works, though a cleaner change for 1st, 2nd and reverse would be nice. I guess there's nothing else that can be adjusted as I can't find any info if there is?

Are you definatally sure the clutch is not slightly dragging?

Adjust the clutch up a little more again and see if it feels any better.,as you mention it felt slightly better after re adjusting?

What thrust bearing did you use?

I was just about to ask the same lol. What clutch and release bearing are you using?

The clutch is an EBC three piece item (new), for the UT models. It included a friction plate, pressure plate and release bearing. I also changed the flywheel for a UT spec item (190mm instead of 180mm).

I'm using the original 70SX clutch cable, which fits and operates fine. I don't need the UT pulley type clutch cable as heat at the rear of the 1500 engine will not have the same issues as the turbo engine.

I've adjusted the clutch a few times. Had it so it was way off the floor, and 1st, 2nd and reverse still had the same issues. Right now the clutch pedal is about the same height as the brake pedal. Adjusting it as per the book, it should normally sit just below the level of the brake pedal.

I don't think the clutch is dragging, because there's no difference in revs between the engine ticking over with the 'box in neutral and with it in gear and the clutch pushed down.

I will try fine tuning the clutch adjustment again to see if a few mm's here or there might make a difference. Just seems weird that it is 1st, 2nd and reverse that give the most problems, whereas 3rd, 4th and 5th appear largely unaffected.

Still, it IS nice to have a gear lever that doesn't flop all over the place, and doesn't feel like stirring thick custard with a big stick like the bottom change 'boxes!

just a guess could it have anything to do with the selector mechanism in the box

Does the top change box not use a completely different oil from the bottom change boxes?

Bottom change is non EP engine oil, but I think the top change uses real gearbox oil?

Rob, it's possibly an internal selector issue. 1st and 2nd often get most of the abuse so they can be the first to go compared with other gears.

Charlie, the bottom changers also use 'real' gearbox oil, only it's the non 'EP' stuff! That's the only difference between the older Fiat 'boxes and more modern 'boxes. Plus I did find out that engine oil and gearbox oil are rated differently despite being essentially the same. Non EP gearbox oil has similar weight and viscosity as standard engine oil. EP gearbox oil is similar though with added EP properties. Not sure if the Tipo based gearbox is meant to take EP oil? Thus, it could be the oil that's causing the issue. There was a thread on here recently (ish), or it might have been on the UT FB page, with a lot of discussion about gearbox oil. I can't seem to find it on FUTOC though? What is everyone else using for (top change) gearbox oil?

I tried adjusting the clutch again today (pedal now lower than it was), and it seemed very slightly better. Might have been an illusion though as I only took it round the block. I'll take it out for a longer run later tonight and see how it fares.

Think I use 75/90 in mine,mind you I used the same in the bottom change  

I can see why the bottoms don't want these ep additives though with there syncros being different.

Can you explain in more detail about the ep or non ep oil please Rich?

30 years this cars been on the road now. But it would appear we are all still in confusion about what oil to use?

Tbh i am still confused lol,i never really looked into it much until you mentioned it mateand have always used ep stuff,my bottom changes have always been worn out before i have even added oil though lol

i think its that the ep additive is corrosive to yellow metals?

I think the main reason not to use it in the bottom change though is due to the syncros on 3rd 4th and 5th.
I am not completly sure what these are made from tbh but i think the ep additive eats into this symcro material and softens it?
Then due to the design of the syncros this will cause much faster wear.

But now you could argue you should not use it in the top changes either as they have brass syncros i think?
I need to look into it abit more tbh but the gtir has the same syncro design/material as a top change and i have always use ep oils in them and never noticed any problems with the oil damaging them.
The manufactuers also reccommed ep oils for the gtir and also the top change boxs i think?

Thete is a bit of info on pils here...
http://www.morrislubricants.co.uk/lubricants/company.asp?wp=91

OK, page 19 of the orange Haynes manual (1983 - 1987) states this:

Transmission (2): SAE 80W/ 90 gear oil (not EP)


Page 19 of the updated orange Haynes manual (1983 - 1988):

2 - Transmission - Multigrade engine oil, viscosity 15W/40 (Duckhams Hypergrade)


Section 0.13 of the red Haynes manual (1983 -1995):

Transmission:
1372cc Turbo i.e. model - Fiat ZC 80/S gear oil
All other models - Fiat ZC 90 gear oil


Porter Uno Manual, page 153:

Lists Tuleta ZC80/ S and ZC90 for most models


Plenty of talk online regarding Fiat gearbox oils. It appears to be well known that the older (1980's and earlier) FIAT 'boxes must NOT be used with EP gearbox oil.

"The reason for Fiat gearboxes needing non EP gear oil or GL-1 rating, is that GL-5 oil will cause you alloy brass syncros to pit and corrode. "

http://fluforum.italiancarclub.com/viewtopic.php?t=1652


Discussion regarding the 124 gearbox, though it also applies to 80's Fiats.

"A note about proper 124 5-speed transmission lubrication.... The yellow metal synchro rings used in the Fiat 124 transmission CANNOT be exposed to EP type gear oil!  These are the gearbox oils commonly available at today's auto parts stores. (GL2, GL3, GL4 and GL5).  The extreme pressure additives in these oil will attack the soft metal synchros and greatly shorten their life.  Watch out for the synthetic oils such as Redline as well.  True, these synthetic oils are SAFE for the Fiat's yellow metal synchro rings, but the synthetic oils are often too thin and too slippery to provide proper protection in the splash-lubricated transmission.  Synthetic oil is simply too slippery to stick to the gears.  The Fiat manuals make it clear....  GL-1 (ie 90 weight mineral oil) is the lube of choice.  Yes, it is thick as molasses when cold, but it is the RIGHT oil for the job.  In a colder climate, an acceptable substitute is a 50 weight (not a multi grade!) engine oil such as Valvoline 50W racing oil.  Engine oil lacks the EP additives and is safe for the Fiat synchromesh rings."

http://www.midwest124.com/Transmission_work.htm


NO! Never use an EP gear oil in a Fiat 131 gearbox. The EP (Extreme Pressure) additives can ruin a Fiat 131 gearbox because they will damage the brass in the bearings of the gearbox. The correct oil to use is Tutella ZC-90 or any GL3 specification gear oil. Do not use GL4 or GL5 specification oils as they are all EP oils.

"Now a 90 grade gear oil has the same viscosity as a 30 grade engine oil so if you cannot get the Tutella ZC90 oil (available from most Fiat dealers) then use a straight 30 engine oil (available from most motor factors). In fact you can use multigrade engine oil in the gearbox but I wouldn't go for a modern and thin 5W/40 (or worse 0W/40) but go instead, as you rightly said, for a 15W/40 or a 20W/50."

http://www.131mirafiori.com/smf/index.php?topic=1922.0;wap2


Search results here:

https://www.google.co.uk/search?q=fiat+non+ep+gearbox+oil&oq=fiat+non+ep+gearbox+oil&aqs=chrome..69i57j69i64.21530j0j7&sourceid=chrome&espv=210&es_sm=93&ie=UTF-8



What isn't clear is if Fiat switched back to more conventional gearbox oil from the late 80's onwards (Tipo boxes and later FIRE boxes). This I do not know, so if anyone is any clearer please let the forum know. What is worth bearing in mind is that many motor factors incorrectly list EP gear oil for older Fiats (my local Eurocar Parts tried to sell me some that their system listed for my old 70SX bottom changer). However, another motor factor (Allparts Automotive) DID list HD40 (diesel) oil, which I believe is correct.

I wonder if my gearbox was failing at such a low mileage (it was making noises from 55K miles onwards) because of incorrect gearbox oil? I know when I first got it and changed the gearbox oil, it did smell like it had EP additives. No idea how long it was running with that stuff, but 20K miles later the 'box sounded like a cement mixer hence my upgrade to a UT top change 'box.

Just seen this Chas. Have you thought of using a cable selector instead of the rods?

Lewey noticed that the top change linkage rods are interchangeable with cable driven stuff from other newer stuff in the FIAT family - Brava, 500 ect.

IIR was running his T jet uno with the UT rods first then switched over to cable - told me the setup is interchangeable as complete units.

Louie wrote:Just seen this Chas. Have you thought of using a cable selector instead of the rods?

Lewey noticed that the top change linkage rods are interchangeable with cable driven stuff from other newer stuff in the FIAT family - Brava, 500 ect.

IIR was running his T jet uno with the UT rods first then switched over to cable - told me the setup is interchangeable as complete units.

I hadn't thought of changing to the cable gear change Louie. Thing is, I'm not sure what the issue is with my gear selection issues. The gear lever and rods/ swivel assembly are all nice and tight, no slop at all. It may be the selectors/ syncromesh in the gearbox giving issues, or it may be the oil I am using (10W/40 semi synthetic engine oil). Sometimes the gears change really smoothly, other times they baulk. Makes no difference whether it's hot or cold. The gearbox itself is nice and quiet, so as the weather is crap/ nights are long I'm just going to leave be until the spring. I might change the oil for something else, just have to see what anyone else suggests to use in the top changer.