New to 75 ts

[GTVeloce]

Really glad to hear you are enjoying the 75 and that everything is running well. They are a great car, even by todays standards. It's surprisingly quick and yet still quite frugal. I'm enjoying driving mine again although I do miss the GTV!

A few suggestions for extra jobs to do that help considerably. Run a bigger gauge wire from the starter to the RHS terminal block and install a starter relay. Also, install two new relays for the headlights/highbeams as the original wiring was insufficient for 25 years of ageing.

Finally, when you need to re-gas your A/C I have had excellent results using hydrocarbons (Hychill HC12) and it's cheaper than R134A. It also lasts longer as the pores are similar to R12, unlike R134A which leaks through pores in the hoses unless they have been all changed which from memory yours haven't been.

[MD]

Hychill HC12.
A good refrigerant it is. A safe refrigerant it isn't.
It is a highly flammable gas. If your air con.system leaks in your cabin and you operate an unprotected ignition source, you could well blow yourself up. This stuff should be banned for automotive application.

Do yourself a favour and read the MSDS on this substance and then make your own mind up.

Apology for contradiction GTVeloce but in the interest of safety, I felt obligated to do this.

http://archive.hychill.com.au/tech/hr600ams.htm

[Divano Veloce]

Took the car for a big run last night and tried the A/C and the air was cool, but so was the outside air.... Its been regassed many times indicated by the stickers on the radiator panel.

I replaced the cable from the starter to the terminal that supplies the fuesbox, thermo fan etc. early in the piece and would say that this is a mandatory fix for all RHD cars

It seems lacking a bit down low, it doesnt seem to have anywhere near the torque of the Berlina (but right now the Berlina wont rev past ~4500 instead starts pinging like mad). So two motors that should be pretty similar feel very different to drive.... one is a tractor, the other a toyota (no torque but power in the revs)

Another very annoying feature of both cars is the petrol fumes in the cabin, especially with windows down..... I will add the vapor circuit to the berlina to hopefully scavenge the vapor but have no idea whats going on with the 75!

[Divano Veloce]

Thanks for the link to the MSDS MD. Looks like its got an odourant in it so one should be able to detect a leak. In my car at the moment iIm more concerned about the petrol vapor!

[GTVeloce]

Yes, in theory, HC12 is flammable. However, in reality, there is relatively a small amount of gas in our systems (a standard 75 takes 270g) and the likelihood of it leaking into the cabin in sufficient quantities for ignition whilst not noticing it is small, I believe.

As to the petrol fumes - there are a few places to start. First, check the inlet pipe to the tank for any cracks. Next, follow the hose from the tank to the separator and one-way valve which are attached to the boot wall. Just pull back the carpet and you will see them. Blow into the valve to make sure it is working. After that, it is just a single hard plastic pipe that goes all the way to the engine bay through the cabin. I suspect if you had a problem after that point you wouldn't notice the smell although, maybe the charcoal canister purge valve is not working and gas is building up in the system and somehow coming back.

I had fuel smell sometimes in the GTV until I finally got the canister and purge valve installed, even though I had rebuilt the rest of the system (in the boot etc) so it could still be the problem but I would start at the back first.

[jazig.k]

I've used the HC12 before and got the lectures about how I would die if I used it. It does have an odour and a UV dye in the one I used (gas the system ourselves as we have the equipment). Worked great. Had no issues. Still living. 

[shiny_car]

Still living.

[Divano Veloce]

Vibration is back!

After removing the GG pins from the old mounts i decided to install a new set i had already purchased... this brought back the vibration. I had a look at the "snubber" which prevents the front end of the tranny hitting the body under hard acceleration and it looked like it was adjusted too low, as in it was touching the clutch housing.... SO i lowered the front end of the transaxle enough to get in there with a spanner and adjusted it up a bit but... it still vibrates!

So with crappy old mounts its ok (probably not great but better than all other instances) but in all other cases its the same or worse than it was when i purchased the car.

So far I have replaced the tailshaft with a second hand one with very good guibos and center bearing support and I have replaced the gearbox mounts.

I am starting to suspect the clutch may be out of balance.... is this likely? the vibration is bad between 1500 and 3500 rpm but is undetectable at high rpm.

[GTVeloce]

Maybe start at the front and work back. Are the main engine mounts ok? The rear engine mount? I pack these up with cut pieces of rad hose and silicon. It helps keep the alignment. Between the propellor shaft and the engine flywheel housing at the back there should be a 7mm gap.

Assuming the shaft is actually ok, then yes, it could be in the clutch. Probably more likely in the clutch housing than the actual clutch. There are two (maybe three - I can't remember) bearings in the clutch housing that can affect alignment. Does the car make a different noise at idle when you release the clutch in neutral? Does it vibrate at idle?

The fact it didn't vibrate with the old, non pinned gearbox mounts but does with the new ones kind of makes me think it is alignment rather than balance as the new mounts would change the alignment or maybe it's just the old ones absorbed some of the vibrations!

[Divano Veloce]

Thanks Julian for putting some thought into this....

I am thinking its something other than balance, well i really doubt its the prop shaft as I've changed it out entirely.

I have a set of new engine mounts that i will install this weekend. I'll also do a couple of things suggested on alfabb including:

loosen all guibo bolts a bit and start motor and let it run for 30 seconds then stop it and retighten
check axial load (tension) on tailshaft/guibos and add spacers as required
Rotate tailshaft 120 degress relative to clutch input at rear guibo
set bellhousing to tailshaft vertical clearance
try not to get mad and break stuff

If none of that works the old mounts are going back in

[Divano Veloce]

Last couple of evenings i managed to replace the front motor mounts and set the clearance between the prop shaft and bellhousing (above the rear mount) without getting mad and breaking stuff.

I loosened the rear guibo to clutch shaft bolts to see if there was an axial load on the shaft. There was a gap, but the gap was only on the lower most yoke and would close up when the tailshaft was rotated (so that the lower yoke always had the gap). This suggested to me that the front of the gearbox was too low. So i added some spacers between the gearbox mounts and the rear crossmember. This removed almost all of the gap and made all three gaps equal. Seemed like a good thing but....

the vibration is still the same, maybe a bit worse......

Another thing i noticed with the rear guibo to clutch shaft bolts loose there was a bit of play in the center aligning bush, about 1mm radial play..... does this mean a new clutch input shaft???

Any suggestions very welcome....

[jazig.k]

In both the rear aligning bushes I recently changed there was a few hundreds clearance... I never measured, just going by feel. There was no way near 1mm play in mine...

Time to measure stuff I'd say...

If the clutch shaft is buggered it could be machined down, shrink fit a sleeve and machine that to size to fix it up [machine between centres since it has a centre in each end].
Maybe a cheap/poor quality guibo? Maybe it was fitted without grease and has flogged the bushing out over time? I don't remember if you put a new one in or not...

[Divano Veloce]

I can measure the guibo on the tailshaft that came out of the car... also im getting pretty good at dropping the exhaust center section and the front of the tranny, should not take long to get and ID and OD of the bits

as for lube, it looks like someone used copper anti-seize to lubricate the bushes throughout the old tailshaft

[GTVeloce]

You mentioned you thought the clutch was sitting slightly low compared to the prop shaft when the nuts were removed, have you checked the rear tranny mount bushing while it is under load? I'm guessing you already have but just checking...

[Divano Veloce]

So far I've installed new motor and transaxle mounts but the tailshaft has been replaced with a good second hand item complete with good second hand guibos and center support.

I think it has gotten better, although there is still a vibration, it feels much more responsive throughout the rev range, as though less power is being lost in transmission.

next i will measure the bush id/od at the clutch input and also do the loosen the engine mounts and center support and give it a rev. I saw on a alfabb thread that JimK used a pair of lasers (one on motor pointing back, one on tranny pointing forwards and the whole arrangement was horribly aligned... I might see what mine is like using something a bit simpler/agricultural.