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Ghibli de Hongrie [ENG]

Publié : mar. 16 janv. 2018 02:05
par spacecadet
Bonsoir!

First of all sorry for the language, I'm a long time reader of the forum but only with Google Translate. I was advised by some members of the forum (Nicolas and Alexis) to write in English as I don't speak French.

I'm from Hungary, bought my Ghibli 2.0L ABS 3.5 years ago from the Netherlands. It was in a nice state, bit much kms (140.000), but with an extensive service history, except the last few years when it wasn't really used.

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The only problem, loud noise, was with the Ranger differential, which I replaced with another used one.

After two years I've noticed a overfueling (oil level was increasing but not with water), and in the end found some faulty temperature sensors which I replaced, a vacuum leak in the back of the intake manifold, also cleaned the injectors and replaced the oxygen sensors. This seemed to fix the issue.

Last winter I was planning to overhaul the whole suspension (rubbers, repaint, etc.) but only finished with the rear part.

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While preparing for the front, I've noticed the well documented crack on the right hand longeron.

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Before doing the suspension I also wanted to verify the power of the engine, and only measured 250bhp on the dyno. So decided to wait for the next winter to tackle these problems.

This is where I'm now, and I'm writing here because I think there is a lot of relevant technical knowledge for these cars (late 2.24, Shamal, Ghibli, QP4) here. I'm still getting to know this car, and I'm not a mechanic, just doing it as a hobby, so excuse me the dumb questions I will come up.

In the last week I've finished pulling the engine, so that the crack can be fixed.

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Now I'm trying to understand what could be the reason of the lack of power. Compression was ok.

When I had the issue with the increasing oil level some workshops said it's the rings and I have to overhaul the whole engine. At that time without knowing too much I just said ok, and started slowly collecting the spare parts. But today I don't yet want to open the engine because I don't think it's in such a bad state. I'll first start with diagnostics to better understand the current state instead of just replacing things. Planning to do a leakdown test and verify the timing first. I was thinking about setting valve clearances, replacing the streched timing chains which I've already bought earlier and setting properly setting up the timing. If these fixes the power great, if not I can still open the engine.



I was also thinking that maybe the turbos are tired, and while I was removing the engine now I found quite some oil in the R.H. turbo outlet - intercooler inlet. Could this be connected to a broken blow off valve? When I was looking for vacuum leaks I've found that the R.H. one had a broken diaphragm so I've also replaced that.

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Peter

Re: Ghibli de Hongrie [ENG]

Publié : mar. 16 janv. 2018 09:31
par bay
Congratulations , Peter ;)

Re: Ghibli de Hongrie [ENG]

Publié : mar. 16 janv. 2018 11:35
par fanch
Welcome on board.

Re: Ghibli de Hongrie [ENG]

Publié : mar. 16 janv. 2018 11:45
par Cedfred
Hi Peter, welcome to the Forum!
I bought my Primatist in Budapest... are you from Budapest?

You may already have found the information, but you have a summary on the Ghibli II at http://www.maseratitude.com/viewtopic.php?f=11&t=4048 ... I will need to update it by the way :D !
You will find some technical Docs at http://www.maseratitude.com/viewtopic.php?f=28&t=138 and the electrical Schematics are at https://drive.google.com/open?id=1t2ZHZ ... Gv51F1EhN3
Note that the engine doc is the same than for the Quattroporte.

I've in mind that if the oil level increase, it means either you have water or gasoline coming in... does the oil smell gasoline?

What about your turbo pressure? when you accelerate hard, the pressure should move to the red zone for a very short time - 1 second or less - and then stabilize in the orange zone.

Re: Ghibli de Hongrie [ENG]

Publié : mar. 16 janv. 2018 13:01
par alpa
spacecadet a écrit : After two years I've noticed a overfueling (oil level was increasing but not with water), and in the end found some faulty temperature sensors which I replaced, a vacuum leak in the back of the intake manifold, also cleaned the injectors and replaced the oxygen sensors. This seemed to fix the issue.
Before doing the suspension I also wanted to verify the power of the engine, and only measured 250bhp on the dyno. So decided to wait for the next winter to tackle these problems.
Now I'm trying to understand what could be the reason of the lack of power. Compression was ok.
Hi Peter,
Welcome !
The above put together makes think it's:
- either a problem with rings
- or dirty injectors and/or not well working engine management.
What do you mean by "Compression was ok". How much ? Cold or hot engine ?
In both cases there is a fact: the engine has run with a diluted oil. Consequence: all bearings could be badly worn. Especially because these v6 are odd-firing and main bearings are very tight, they wear out fast.

A really worn turbo becomes very noisy. If it's not it's probably still making the proper boost level.

As I've already told you I don't think you'll cure performance problems with new chains and (probably not needed) valve clearance adjustment. On turbo engines they don't count that much. Unless timing belt slipped.

The rebuilt rear looks great !

Re: Ghibli de Hongrie [ENG]

Publié : mar. 16 janv. 2018 18:53
par plm
Welcome Peter,

seing that a lot of "maseratitudisti" do speak engligh, I propose the whole forum switches on english... :mrgreen:

Re: Ghibli de Hongrie [ENG]

Publié : mar. 16 janv. 2018 19:03
par William
Üdvözlünk! Gratulálok. Itt van olyan ember, aki segít.

Re: Ghibli de Hongrie [ENG]

Publié : mar. 16 janv. 2018 19:20
par plm
Oh noooo,
an other language???

"$*+£§&<; :Maze ?$€ !!!!!" :D

Re: Ghibli de Hongrie [ENG]

Publié : mar. 16 janv. 2018 20:37
par William
I translate : Welcome. Some members can help you.

Re: Ghibli de Hongrie [ENG]

Publié : mar. 16 janv. 2018 21:14
par ghibli30
Hello Peter,
I think you face at least two problems. Oil level might be related to worn rings I'm afraid, as if it is not water, it is petrol, not better for the rings and other lubricated parts.
Then lack of power is not easy to diagnose. Maybe rings of course, but also SEM valve, inlet leaks, and as Alpa mentioned, also faulty management or injectors.
We will probably need some additional details to help in an efficient way......

Re: Ghibli de Hongrie [ENG]

Publié : mar. 16 janv. 2018 21:51
par Blu Sera
Hi Peter ! Be warmly welcome on Maseratitude ;)

Re: Ghibli de Hongrie [ENG]

Publié : mar. 16 janv. 2018 21:59
par Froggie
+1
Good to see the attractiveness of Maseratitude to foreigners.
Now, to complete the loop, you have to work out your French so that one day you can surprise us!
You seem quite knowledgeable on your Maser, btw...

Re: Ghibli de Hongrie [ENG]

Publié : mar. 16 janv. 2018 22:02
par gemini
Hi Peter, nice to hear from you again.
I followed the work you did on sportmaserati (for all, take a look here for the suspension overhaul, you'll find a lot of very useful pictures: http://www.sportsmaserati.co.uk/showthr ... n-overhaul), congrats.

I can't understand how you could have good compressions AND worn rings. A leaking injector was probably the culprit for the oil increase, and, hopefully, it didn't had the time to "wash" the cylinder/destroy the ring.

250HP is not that bad for an italian lada-shaped pile of rust ( :mrgreen: ;) ), check for boost leak, check your valve clearance (it will not take to much time, and despite of the opinion of alpa, I can say that I saw a big improvement in the performance of my ghibli after the valve adjustement -full disclosure, the valves were replaced 1000km before) , check the timing (don't rely solely on the old marks), check your sem valve, check the wastegate and you should find the cause of your loss of power.

As you've already removed your engine and you've bought the chains, replace, but it won't change the power your engine produce.

Re: Ghibli de Hongrie [ENG]

Publié : mer. 17 janv. 2018 01:02
par Dom3200
Hi Peter and welcome and congrats for the very nice job on the rear.
I heard that replacing the camshaft timing chains is useless if we don t replace the "wheels" (I know it s not the correct word :? ) as well as the dents should be worn too. Is that correct ?

Re: Ghibli de Hongrie [ENG]

Publié : mer. 17 janv. 2018 01:58
par spacecadet
Thanks for the welcoming words, even Hungarian, I'm flattered :)

Yes, I'm from Budapest. Unfortunately I haven't seen the Primatist, only heard about it and also talked to the owner after he sold it.

I've sent the injectors for cleaning and measurement when I verified the sensors because I was also suspecting an engine management issue. Some of them were dirty indeed, leaking or producing a bad spray pattern. At that time I checked all of the sensors except the MAP sensors. Also checked the SEM that it was switching and not leaking in unwanted directions.

Turbos are working as described, boost goes slightly into red and comes back a bit. If that's the case they shoudn't be in a too bad state?

About compression: the first workshop measured 6.5, which I've found too low. Dyno test was done later after I checked engine management, and I don't think with 6.5 it could produce the power measured. I also checked it myself, right now my notes are not with me but as I remember they were around 7.5, hot and cold, and also tried a few drops of oil to see if the problem lies with the rings. The numbers didn't change. I took it then to a different workshop working only on engines, and they also got similar numbers.

I don't think (hope) bearings got destoryed because I only drove a few hundred kms after the last oil change, and also sent the oil for analysis and they couldn't measure significant amount of fuel in it.

If there would be such a significant wear on the rings that would be visible on a leak down test no? So I'll start with that.

I like the Lada reference, we had a lot of them here, so the first words in my family was: What is this Lada?! :D But I have a measurement from 2006 with 283bhp (at 95'000 km) , so I would like to reach that number at least.

Re: Ghibli de Hongrie [ENG]

Publié : mer. 17 janv. 2018 23:27
par alpa
I'd rather say Delta HF, not Lada.

Ok so compressions seem OK.
Then check timing, may be it was altered.
But I'd still check management and fueling. For example are you sure richness is correct at full power ? Fuel pump or hoses inside the tank may be leaking, fuel pressure regulator may be out of spec (it's adjustable, just remove the cap on the top of the regulator).
Injector cleaning ... I don't have good experience on these old injectors, once they don't work they don't work. Just one not well working injector is enough to make big difference, it's all about richness and thus combustion pressure disbalance,

Measuring power is tricky and to have reliable numbers you need a good bench that extracts transmission losses. What does not lie is time measuring, say how long does it take to get from 2000 to 7000 rpm in third gear. And compare with another car.

Dom3200, chain wear out by elongation (on segment axles), gears don't move.
gemini: having to re-adjust clearance after engine overhaul is not surprising, it depends on the quality of the seat work. But once it's good it's good for a long time. If it moves it moves by say 0.05mm, you won't feel difference on a street turbo engine. This is my experience, I've never had to adjust underbucket shims on my old (up to 250mkm) Alfa engine.

Re: Ghibli de Hongrie [ENG]

Publié : jeu. 18 janv. 2018 12:42
par ghibli30
Clearances were still OK two years ago on my '97 Ghibli GT, 38 000 km, not a single valve to adjust.

Re: Ghibli de Hongrie [ENG]

Publié : sam. 20 janv. 2018 12:17
par spacecadet
That's good to hear that valve clearances don't go easily out of spec.

I'll then check timing, leak down, and recheck management and fueling too. I've only checked pressure at idle, that was ok (3 or 3.5 bar whichever should be at idle).

This will take some time because I only have time to work on this on some weekends.

Re: Ghibli de Hongrie [ENG]

Publié : lun. 9 avr. 2018 23:45
par spacecadet
Sorry for the long silence, but finally I had a whole weekend to work on the engine.

First measured the valve clearnes. The intake valves are mostly ok on the tighter end 0.35, a few 0.30 (factory spec is 0.35-0.40), but the exhaust valves are nearly all too tight, most is 0.40 a few 0.35 or 0.45 (factory spec is 0.45-0.50). Still no huge deviations.

Then also checked the valve aperatures at TDC.

Right block

Exhaust valve: 0.65
Intake valve: 0.60

Left block

Exhaust valve: 0.60
Intake valve: 1.05

Factory spec is: exhaust 0.65-0.75, intake 0.90-1.00

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The big delay of the intake side on the right block is probably because of the slack in the chain. Strangely the chain on the left block is very thight, no slack, that's why the values are much more close to the factory values. Is it common that the right chain wears much more than the left?

So I can either adjust the difference between the exhaust and intake cams by changing the pin in the sprocket in the back, or just change the chain since I already have it. By the way found the manufacturer mark on the chain: https://www.reginachain.net/ They mainly do chains for motorcycles, another Ducati connection like Nigusil?

Either way I have to remove the cams if I want to adjust the valve clearance. Is there anything I should prepare for? First remove the timing belt and then simply remove the cam caps?

I also found some exhaust leak around the exhaust manifolds so removed those as well to replace the gaskets. Unfortunately one of the manifold has a small crack which has to be addressed before it gets bigger.

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Finally I have a questions regarding the front axle. I would like to remove the stub axle from the carrier, but no luck. Tried with a shop press, but nothing happend with 3t, and I was afraid that the carrier will break. The workshop manual also didn't mention anything special. Is there some trick?

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Thanks

Re: Ghibli de Hongrie [ENG]

Publié : mar. 10 avr. 2018 00:04
par Froggie
Can't help for the chain or valves and the axle.
Hope others will chime in.

I'm curious though wrt your exhaust manifold crack.
Did you smell the exhaust leak or had a check engine light before removing it?
And how do you intend to address it: drilling/welding?