Gearbox/clutch problem, won't shift into some gears

Hi All, my newly purchased 550 seems to have more problems than just the fuel pumps (another thread from a week ago, but that looks to go into the right direction)
When I drove the car home from the garage, with a cold engine, I noticed that shifting was very hard.
The clutch pedal feels normal, and driving away in first worked without problem, as well as shifting into second. (which is a common issue, but not this time...)
But third and fourth was very, very hard to shift the lever into. Even after it warmed up.
As I only drove in 5th gear on the highway after that, with 90 km/h because of a SDL (limp mode which turned out a badly repaired right fuel pump), I did not investigate further.
Now I am waiting for the last parts to repair the pumps myself, so in the mean time I am looking into the gear shifting problem.
When I press the clutch pedal, I can move the lever into first, second, and fifth and sixth gear, albeit with more force than feels normal. I can shift the box into second for example, then I can't turn a wheel, and when I shift back to neutral the wheels can be turned. So it does shift.
But third and fourth gear I can't select at all, it simply will not go in the slot.
The lever can be moved in neutral from left to right without much force, so I do not think it is the lever system.
Please take into account, all is with the engine off. And even when I get the engine running again when I finish the fuel pump repairs, I am afraid to drive it before I have solved this problem.

Anybody any idea what might cause it?
I do not see leaks around the master cylinder (pedal side or engineroom-side) , and the brake/clutch fluid level seems normal. No leaks at the inspection hatch underneath.
Pumping the clutch does not make any difference.

I have searched a lot , but these exact symptoms I have not found anywhere.
The car has stood mostly still for 4 years , does gearbox oil survive 4 years of non-use?
Is there a flushing fluid for these boxes?

 

Thanks both for the suggestions and help!
I just come back from bleeding the clutch (first filled it up to over the max to prevent air entering), and with every pressing of the pedal, around 7 or 8 cm of fluid filled the plastic bleed line I connected. After 5 pumps without bubbles I had my lovely assistant stop.
So I assume the clutch is now bled , and the system moves fluid, so must give at least some pressure on the clutch slave cylinder/bearing.

But no succes, still I can't select reverse, third or fourth. I have not checked the adjustment possibilities, that will be the next step.

I ordered valvoline 75W90 as I read good comments about that from 2 persons here on the forum, and Redline and Torco and Amsoil are very hard to find over here in The Netherlands. Will change the fluid in a few days when it arrives..

Some things I was wondering about:
- when the clutch pedal is pressed, I can see through the hatch below that one plate is moved about 1 mm, and another one 5 mm further on the system, also 1 mm. (can't tell why there are 2 plates that move...) So a movement of 2 mm in total. Is that enough in this system? Should I make some pictures ??

- There is no difference in feel or reaction on the gear lever action whether I press the clutch or not.
Does that point toward the clutch not completely releasing?

 

Ok, thanks for explaining.
I looked into the shift linkage, and from underneath I can only unbolt the bolt that connects the rod to the gearbox actuator itself. But that bolt needs to go into the hole again, so not much to adjust there.
The rubber block is not there for adjusting, right? And the 2 bolts connecting the rod to the block are on a splined shaft , so only can move front and back and not left and right.
So I can't see the location where I can adjust left to right, but maybe it is inside the car , connecting to the gear lever? On my 355 there is no exhaust underneath , so the whole linkage can be seen , but I forgot how I adjusted that one 4 years ago...

Other point, I checked the oil level, and it is overfilled by at least one cm over the max on the dipstick. I know that this can cause all sorts of problems in the end, but maybe also difficult shifting with the engine off and the internal shafts and wheels not rotating?

With a little more force (not too much of course), I was able to get third and fourth and reverse again, but all gears feel very sticky and stiff, and third and fourth the most. It does not feel as if adjusting the linkage would help, but I won't ignore the advise of course.

What I still do not understand , is why depressing the clutch does not make any difference on stiff shifting when the engine is off. On all my other cars it does...
My 355 shifts very nice when depressing the clutch (engine off), but not when I release the clutch pedal...
Or is a car always hard to shift engine off, no clutch, and I do not feel that difference because it is already very, very stiff?

 

Thanks all for your reactions. I am really glad I can ask questions and get advises, it is not funny at all when you buy a 550 with the promise of the garage to deliver it repaired (fuel pumps, another topic I started..), then you barely make it home with 6cyl instead of 12, and realize there is even more wrong with the car.
Yes PPI, I know, but as this is my 15th car( Porsches, TVR, Aston, 2 355's) in 20 years without an official PPI, one gets a bit overconfident in its own judgement, and that comes back with a vengeance...
Ok, back on topic,
Even though 3 and 4 and reverse are hard to engage, they are there when more force is applied.
And the lever leaned a bit to the left of the slot when in 5 and 6, and in the middle for 3 and 4 , and to the right when in 1or 2.
So to be sure, I removed the gear slot, so there is no forced lever "path" by the "fingers" of the slot, but it stays the same: all gears hard to engage, especially 3 and 4. So it looks like adjusting the linkgage cannot be improved,as it already seems well aligned with the slots.

The feel of the box when engaging, however, is positive, if not for the high level of force to apply, to get to that point...

And no difference whether I depress the pedal or not, no easier shifting, I always need much more force than expected to shift.

Apart from the fact that the level in the box is 1 cm to high (above max), the gear oil is clear green.
Could it be the wrong fluid as Yelcab already suggested with renewing the fluid? According to an old invoice from 5000 miles ago (but 15 years old!), from the official Dutch Ferrari importer Kroymans, it was 75W90SX , no brandname, but I assume AGIP or Shell. But why would this highly experienced dealer overfill...

I ordered Valvoline top of the line 75W90 a few days ago, but delivery is delayed for a week (normal 75W90 I can get now, but I decided to do this right), so I can't refill it now.

Would it be any good if I drain the box already, and see if the feel changes with no fluid at all? Should it go very light right away? Of should I not expect any difference?

 

Ok, update, I removed the gear rod connection to the gearbox.
The gear lever then shifts very, very easy, no obstructions to be felt.
So it could only be the balljoint connector to the box, or something inside the gearbox.
After thoroughly greasing that last ball joint to be sure it moves with ease, I reconnected the rod to the box.
But no succes, all gears are still very stiff, 3 and 4 the most.
So it is the gearbox itself.
What in the gearbox can make gear changing very hard? All gears can be selected, it really only is the needed force that is a problem.

The only thing that is left for me to do is draining it and refilling with the oil that will arrive end of next week.
But if that does not help, is there any other thing to try?

 

No problem at all of course, I am glad you both reacted.
So is there still need to replace bushings when the system, disconnected at gearbox by removing the lock bolt, moves very easy and light?
And by bushings, are those the 2 sleeve bushings nr 26, or do you mean nr 8 where the ball rests in? As that bushing is no longer available...
I hope this diagram does not violate any posting rules...

 

Thanks. It is clear.
I removed bolt 36 before, but will have a go at 29 tomorrow, and follow the directions.
And I will report back if the drain plug picked up metal. I already noticed it was clear greenish, so any metal parts the plug would miss will certainly directly catch the eye.

 

Ok, I tried adjusting with the 29 screw, but after aligning, it stays the same: force needed to shift (engine off), 3 and 4 the heaviest.
After leaving the lever in say 3, a day later much force is needed to get to neutral. After that (still engine off, it has not run for 3 weeks now) still much force is needed, but it gets a tiny bit better. But the next day all is back to being stuck etc.

The new oil still has not arrived, delivery has been postponed for some extra days as it turns out to be a rare oil, this Valvoline 75W90 total Drive...(but not as rare as the Redline over here...)

In the mean time I have spent some time (actually, a lot) in searching for gearbox problems that sound familiar.

@ Yelcab, many brands of gearboxes suffer from problems with the detents, for example on a M3 BMW ZF box I read that the fifth gear is notorious.
(I have a Z3M , but my 5th gear does not have the problem so not always...)

My 550 has been in a collection for 4 years, driving only 10 miles in that period. So maybe the 3/4 detent is indeed sticking as it has been above oil level (correct?) for a long time, in that case applying constant force on the control rod (nr 39 below) making shifting heavy.

When I look at the diagram of the gearbox, it looks like the detent is not lined, but simply machined into the big main house, to insert the spring and ball.(nr 35 / 36)
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I searched the whole internet for pictures of the inside of a 550 box (or very similar), but I can't find any.
So I just have the info above.
Would it be correct to assume that the cover nr2 can be removed (after removing the exhaust pipe that sits next to it), to then gain access to the detent?
As far as I can see, the detents will come out on itself when the cover nr 2 is removed. (not unlike the 308 box)
Has anybody done this before on a 550 or 456? Or know of pictures that show the inside behind cover 2?
I am always anxious to remove a part that is springloaded...

As heavy shifting action on a running box can be caused by bad synchros, I do not believe this is the case as all is aligned when I shift it into 3 or 4 from neutral, and it stays stiff. (the synchro's do not have to spin because the shaft does not spin engine off, in a situation where I shift from neutral to 3, repeatedly)
So that leaves a detent problem (hopefully), or a bent shifting rod, or partially seized bushings nr 46 (or is that too rare to ever be a problem in reality?)
Thanks for your knowledge and opinions!

 

On the Eurospares site all the numbers are explained, so that helped me a lot in identifying
Nr 39 is the 3/4 rod, and the detent that is pictured is indeed for that rod.
The 5/6 detent is not pictured, but the hole is visible just below the 3/4 detent.
The 1/2 detent is nr 35/36, on the other side of the box somewhere and reverse is not pictured either.

When the dog-teeth were partially broken off, that would normally affect just one gear, right? The situation is the same for both 3/4 , and reverse.

I have made a picture of the box in place, but the exhaust and the support is blocking the view.
BUT: Monday I bought a 550 gear box as a spare, in case my box is really not good. It was delivered today, from our neighbour country Germany. Really fast!
It was a risk as I can't check the condition of the spare box (said to be good, from a 14000 mile 1998 car), but at around 3500 usd I thought it was well worth the risk. Even if it is not totally good, split-up in parts it is worth that amount I guess.
So I can always open up the spare box, but in case I disturb matters by opening, I prefer to open the original one.
(but first flushing, and new synthetic oil.)

So I was able to take a better look, and the only way in, is the shift selector housing...the other detents are hopefully accessible from the outside...but no signs of where...

The original gearbox in the car:
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the spare box, same side as above, just a little more from the side/top
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the other side, no inspection cover nor blocked caps for the detents...
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Hi FatBillyBob, very nice of you to take the time to dive into the matter (and thanks to Yelcab, Wmuno, MerlinTech, Island Guy as well, really nice to see that help is available!)
I will try the steps as you described them, even though I fear that the problem indeed is inside the box. But as the nr 29 connection is not hard to reach, it is a 10 minutes job to be sure about it. Will do it this weekend hopefully, as I am in the middle of another job: cleaning the injectors (I repaired the "repaired" fuel pumps, other topic, but want to know the condition of the injectors).

If the brand of 75W90 does not matter, I will use the cheapest synth I can find to see if it helps. In The Netherlands that would be a brand like Kroon or something like that. Maybe they used a full LSD oil, which I understood is not the right one for this box regardless of its LSD.
And I will carefully inspect the old oil for particles. I have several transparent buckets, so excessive wear will show itself in swirls of metallic.

I will keep you all updated!