4200/GP/QP Transmission and Ancillaries

[Zep]

As Catman says, it seems extremely unlikely that engine operation should affect system pressure. Perhaps, more likely, is that you have more leak by from the solenoids after a shift than after it has been sitting. Or perhaps the fluid is contaminated and viscosity reduces more when it is hot, causing more leakage.

 

[lambertius]

It seems super strange to me too. The difference is stark though. As soon as I fire up the engine (moving or not, neutral or in gear). the pressure falls much faster.

If I hold a gear and log the pressure while I'm moving (say in 5th) the the pressure also falls much faster than engaging the same gear with the engine off and stationary. I feel this is normal (though I couldn't explain why if I tried) as on Craig's site he says that the test should be performed with engine running. I think I've just stumbled across my accumulator being on its way out while in the process of trouble shooting in general.

I did try shifting only when pressure was at max - made no difference to the harshness at all. So far the only thing is lifting off the throttle to shift. And again, that comes down to some people say they need to do that, some people say they don't.

 

[TimR]

Dear Lord give me a manual everyday of the week !

 

[lambertius]

Dear Lord give me a manual everyday of the week !

You could probably convert these to stick...

That said, if there were proper manuals, or even just another car I could get access to this would be so much easier!

Any Perth boys on the forums willing to let me visit and get some base line data?

 

[Zep]

It seems super strange to me too. The difference is stark though. As soon as I fire up the engine (moving or not, neutral or in gear). the pressure falls much faster.

If I hold a gear and log the pressure while I'm moving (say in 5th) the the pressure also falls much faster than engaging the same gear with the engine off and stationary. I feel this is normal (though I couldn't explain why if I tried) as on Craig's site he says that the test should be performed with engine running. I think I've just stumbled across my accumulator being on its way out while in the process of trouble shooting in general.

I did try shifting only when pressure was at max - made no difference to the harshness at all. So far the only thing is lifting off the throttle to shift. And again, that comes down to some people say they need to do that, some people say they don't.

I’ve had a brain wave. When the engine is off, the clutch is fully engaged. When running it is disengaged, except when the car has been sat at idle for more than 30 seconds out of gear. So, perhaps the difference is that your clutch actuator is not very happy.

 

[safrane]

Linked to the above... when my tangs collapsed I could cycle gears with the ignition on but engine not running, however it would try but fail when the engine was running and propshaft rotating... and the latter involved far more pump activations.

 

[lambertius]

I haven't looked into the actuator for the clutch system. The way I understood it is that the clutch is actuated from the same hydraulic system and has its own solenoid? L009 is the plug for it.

From what I'm reading, the clutch line needs to be bled separately to the actuator? Any good guides on how to do that on this car? I've messaged my mechanic, I'll find out what he did with it. We're learning this as we go so it may have been missed, might have some air in the line.

From what I can see there are two bleed points, I'm assuming you just have to crack the lines and run the bleeding procedure same as the actuator to keep the system pressure high. Looks like one of the bleed points is inside the bell housing... oof...

 

[Zep]

Yes, from the same system. Yes, you can bleed it without removing the gearbox.

https://www.sportsmaserati.com/index.php?threads/f1-bleeding.15882/post-361008

 

[lambertius]

One of the guys on the other forum picked up on the clutch as well and asked me to check the SV rates (this is way out of spec from what he said). I'm not 100% if it means the solenoid is dead, or if there is air in the clutch system or what (waiting on a response). It does explain though why the pressure is dropping so fast when the engine is on.

 

[Zep]

Here is a link to a page where someone else has measured the same readings. That will give you some idea of what normal is. I searched leakage rates. There may be more for you to read.

https://www.sportsmaserati.co.uk/index.php?threads/f1-pump-priming-intervals.22099/post-622312

 

[lambertius]

I eventually got the car high enough off the ground that I could bleed the clutch bleed point. What an ordeal! It was super difficult, as I could only bleed a little bit, then had to get to the other end of the car and pump in more hydraulic fluid. I did pull out a significant amount of air. When I drove the car it was like a new vehicle, but alas it was not to last. I was really quite surprised at how different the shifting was to begin with, but as the car warmed up it went back to its old ways. The Oil Leakage with SV Not Triggered has dropped to 15cc/min, but with triggered has climbed to 130cc/min. I don't know what that means for what I've done, but I'm still fairly convinced there is air in the system due to the difficulty of bleeding it. I'll be getting it up on a hoist again shortly and some help to do it properly again.

I also ran down to the local Ferrari dealership today and had a friendly chat and went for a test drive with their service foreman. He thinks that my car drives better than average, and that generally they shift rough in auto mode. We played around with a few clutch settings and that has changed the way the clutch engages but I'm not convinced about the harsh shift yet as I've been looking through some training documentation from the time. I've highlighted some interesting bits - there is also the description of calibrating the clutch positional control (basically run the car for 10 minutes).













I just put some of that in case it helps someone in the future, but some of it would imply that the TCU does indeed force the engine to cut out to rev match which is why I still think there is something not quite right.

However, by sheer coincidence they traded in a black 07 Gransport today and once its ready I can take it out for a test drive to get that back to back comparison. I couldn't drive it today due to some issues with the brakes. They did let me hook up my launch to it and I was able to check out a few other details so I can answer a few questions that I (and nobody else) had!

1) The Selespeed TCU is the correct TCU on the 07 car. This is what it looks like disconnected:



2) The 'second version' accessibility from the Launch does not work on this car either, but it does work on the earlier TCUs.

This would seem to rule out a failure with the TCU itself.

 

[CatmanV2]

It would seem obvious to fix the clear problem before looking for others? i.e. that leakage rate?

C

 

[lambertius]

It would seem obvious to fix the clear problem before looking for others? i.e. that leakage rate?

C

You're right, but unfortunately I'm still waiting on the parts so making do with what I can at the moment!

My wonderful fiancee helped me bleed it when she got home, so it took 15 minutes and was super ultra easy and definitely no air in the system now. If I drive the one down at the shop and it shifts like mine I'll be happy to call it there (and still change the valve) as bleeding it again has made a difference, though not as substantial as this morning. Another little bite from the apple. After bleeding again the not triggered value has dropped below 10cc/min, so at this point it is safe to say my accumulator and pump are healthy - just gotta sort out that clutch valve! The rpm still climbs before engagement, though the impact seems to be reduced.

 

[tulit]

When are you taking the valve leakage measurements? They tend to wander during operation. I’d recommend a short drive and have someone monitor how they look over time (or log a drive with them).

Not triggered target should be around 30cc/min. The triggered target should still be okay up to about 60cc/min in my experience.

Can you share your pump timing plots both with engine off and engine on in 1st gear (with brake depressed). You can infer a lot from that on the general health of the system as well.

P.s. you seem to have a very accommodating/helpful Ferrari dealer there. Ours wouldn’t even talk to me if I brought a 4200 in


Sent from my iPhone using Tapatalk

 

[lambertius]

I followed the instructions for 'calibrating' the valves:



I then measured when that was complete.

I got 5cc/min and 130cc/min the last time I took the measurements. I did log them while driving briefly but didn't pay much more attention than 'one was in range, one was out of range'. I'll log a drive tomorrow and some stationary data and post it up. Once this is all worked out I'll consolidate this into another thread so people have some reference data to help diagnose issues in the future. Between my car, the one at the dealership and yours it should be a good data set.

A friend and I made this video a few years ago at Scuderia Graziani in Sydney. The owner is Tony Graziani and he opened up the shop on a Sunday just for us, stayed in the office his whole day off, made us coffee and told us stories about how he ended up with a garage floor made of marble. One of the stories was about how he got started as the only Maserati dealer in Australia (before the GTs came out there were no Australian delivered cars, they are all UK ordered cars which were complied for ADRs). If you buy an 'Australian delivered Maserati' it will have his signature in the book, if it doesn't it was a private import so spent at least some time in the UK.

A few years later I caught up with him again and asked him why he was so accommodating and he said, 'You seemed nice, and just because you can't afford a car now doesn't mean that won't change. Where else will you go when the time comes?'

This is a really long winded way of saying that if a dealership isn't willing to accommodate an enthusiast they're selling the wrong cars.

 

[lambertius]

I was back at the shop today and got to snap a photo of the oil filter from the original transmission:



The black stuff is fine metal - probably the accumulation of the natural wear from the diff. Without changing the oil, that circulates through the transmission and will shorten life in the bearings and LSD. In my case, 7 years and 60 000km is enough that you can feel it while driving.

Back to the matter at hand:


Engine Off

Greater than 3 minutes for pump cycle time.




Engine Idle

Was idling for at least 20 minutes in Neutral



Engine Idling in First Gear

At least 5 minutes idling with my foot on the brake in first gear. Leakage rates climbs to between 130-140cc/min.

 

[Zep]

They did let me hook up my launch to it and I was able to check out a few other details so I can answer a few questions that I (and nobody else) had!

1) The Selespeed TCU is the correct TCU on the 07 car. This is what it looks like disconnected:

View attachment 66488

I have to admit to being slightly baffled by this. At least two people posted the TCU software list which confirmed that, from this picture, you had the correct TCU.

 

[lambertius]

Having the correct TCU software version doesn't eliminate the possibility that the TCU isn't working correctly.

Finding unusual behaviour with RPM matching and being unable to interface with the TCU as expected (and as I was able to do with an earlier car) are indications that the TCU isn't behaving correctly, but without any point of reference or context how can I know? To make it worse, as my car was never working correctly when I got it I don't even have a normal reference for this specific car. By accessing that car I could verify that the specific TCU used in a 2007 year model car running the v49 software doesn't interface with the scan tool the same way that previous versions do. This goes a long way to eliminating the TCU (and therefore the software control side) as being the(an) issue. Once I get to drive the car with the scan tool hooked up I can compare the Engine/Gearbox RPM profile and I can confirm if the RPM surge on up shift is normal. There are no track changes on software releases for these systems so there is no way for me to understand what is a system fault or an intrinsic fault. Depending on how I read different technical documents my car is either shifting incorrectly or the engineers were Dennis Nedry. Either way, I want to know for sure and this is just one step towards that.

And for a bit of extra context, I was getting random power surges throughout the car which had fried two headunits, speakers, switches, window regulators and various other gremlins. I can't take it for granted that my TCU wasn't damaged by this. It was the OEM amplifier that was causing the trouble by surging through the ground plane.

 

[lambertius]

So an update lads.

I went down to Barbagallo who have the Gransport for sale and it is now ready to drive. The car has been maintained by them since it arrived in Australia, and it really shows maintenance over mileage! The car has 112 000km (though I think it is actually in miles) compared to my 126 000km, clutch is similar age with both ~50% remaining, they're both 2007 LEs running the same TCU software and they're both black.

I needed to convince the sales guy to let me drive it for 5 minutes as he wasn't too keen as I had already told him I wasn't planning on buying it, but he gave in after some gentle persuasion. So what did I learn?

1- The engine definitely surges during gear changes. This is super counter-intuitive, and is half the reason the clutches get eaten out so quickly for sure, but this is 100% confirmed behaviour now.
2- In auto mode the car was super smooth whereas mine was not.
3- Wringing it out the car behaved almost identically. I believe this is because the SV is proportional, and when the demand is greater the leakage is relatively smaller.
4- Taking off and moving around in parking lots is significantly better in their car.
5- My AC is next level.

So my car hadn't had the hydraulic fluid and gear oil changed in ~7 years. This one had been done regularly.

As luck would have it, my spare used ancillaries arrived today. Without access to a hoist, I was only able to change one solenoid rather than the whole power unit - coincidentally, the clutch solenoid. I don't usually say this about wrecker parts, but I genuinely believe this came off a very low mileage car!



Squeezing my hands through this tiny cap in the heat shielding I was able to change the clutch solenoid in situ. You can see my shiny new solenoid in place.



So what was the result?

1- Pump activation has dropped to once every 3m13s while the engine is running from once every 15s!
2- There no shudder on take off, I had previously put this down to a hot-spotted flywheel.
3- Because the shudder had stopped I was able to significantly soften the clutch massively improving the drivability of the car in the real world.
4- Gear changes are no longer accompanied by a lurch
5- Leakage rates have changed from 140cc/m to 30cc/m (and still dropping) and 6cc/m to 27cc/m (stable)

Gear changes are still loud and clunky, so once I get access to a hoist I will pull the whole power unit and swap the whole assembly. As I've learned more about what was going on, I don't think any one part has failed, but everything has been worn out and an accumulation of small errors has given the impression of a big issue.

When I bought the original plan was just to swap in a completed gearbox with ancillaries attached, but with a few logistical issues I decided to do it piece meal to try and learn what was going on even though I had already purchased all the parts.

I now believe that the original gearbox had a sloppy diff from excessive wear. This was the binding at low speeds that was making the car somewhat unpredictable to turn. This was caused by 70 000km of no oil change which resulted in fine metal debris throughout the oil, further increasing the wear. When we changed this we bled the system which improved the ability for the system to change gear when revving out, but the excessive leakage was preventing the system for engaging the clutch smoothly at lower speeds making auto mode completely useless. Changing the clutch solenoid seems to have allowed the system to control the clutch timing greatly improving how smoothly the power goes into the gearbox.

If anyone has a theory or explanation for why the leakage rate increased for the clutch SV not actuated, I'm all ears. but my current guess is it is probably just a measurement error covered by the severe leakage of the clutch SV. This would seem to indicate to me that the clunking of the actuator is probably related to the gear selection solenoids as they are also proportional flow type, and I see the same behaviour in that the harder I drive the less of an issue it becomes. I'm optimistic that changing the whole unit will finally resolve the transmission behaviour.

I can say now with absolute certainty - if you are one of the people who also has a transmission that is perfect when you drive it like a manual (lift off with gear changes) that is an indication that the transmission is in poor health. If you're shopping for a car, take note of the behaviour I describe in this post! The transmission is absolutely meant to engage smoothly when in auto and driven easy. You should not need to lift off the throttle to drive the car normally.

 

[safrane]

Thanks for the update... which reinforces the need to service by the book!!!