Ghibli engine rebuild or not

spacecadet

Junior Member
Messages
242
#1
I would like to get your opinion on this.

Last (and first) time I was on a rolling road my Ghibli was measured to have 250bph. I thought that probably the engine and the turbos are tired after 140k kms, so I started collecting all the spare parts needed for a full (top and bottom) engine rebuild.

A month ago the timing belt was changed, 3 years passed since the first timing belt change which was done when I bought the car. And it turned out that neither now nor back then was it properly timed, just eyeballed to the existing marks. Now it feels even more weak then it was. I'm pretty sure the timing chain was never changed, actually it already has a slight noise if listening carefully, and after removing one of the cover there I could see a great amount of slack in it as well.

This means I definitely have to pull engine, but I'm not sure about doing the rebuild now given that probably the timing is quite off. I either replace the chains, adjust valve clearances and properly set the timing or I do the full rebuild. I'm leaning towards the first option hoping proper timing would give the numbers closer to factory values and I could run the engine further while keeping the hard to get spare parts when they are really needed. Also it goes against the rebuild that the engine is feels healthy otherwise, compression ok, not a big amount of leakdown, no smoking. If I would choose the rebuild I wouldn't have to pull the engine again (though I guess would be much faster for the second time) and would be fine for a really long time as I'm only doing 3-5k miles yearly.

Thoughts?
 

conaero

Forum Owner
Messages
27,154
#2
Go the easy route first. Replace the chain, double & tripple check the timing, do a compression test and inspect the valves and play in the turbo shafts.

If it ain’t broke don’t fix it!
 
Messages
1,579
#3
Chain replacement plus timing and valve lash adjustment in my opinion.
But would not hurt to do a compression test before just to know how worn (or not) the cylinders are.
 

2b1ask1

Moderator
Messages
13,448
#4
Compression test for starters. I wouldn't have any quarms about a full rebuild myself as when done it would see you out! That said I get pleasure from rebuilding oily bits!
 

spacecadet

Junior Member
Messages
242
#8
Thanks for the comments. I also think that fixing what is known to be fixed is the way for now.

Compression test for starters. I wouldn't have any quarms about a full rebuild myself as when done it would see you out! That said I get pleasure from rebuilding oily bits!
Me too, would love to do it and would do it as precise as possible but I just don't have the expertise. I have only done a head so far, and this is not the engine I want to practice on. That means I have to find someone who can be trusted. I found someone actually but with quite a big queue.

Are you talking factory timing marks, or marks from a previous belt change? They may be incorrect.
Marks from a previous belt change, those are from a known indy workshop, should be ok but still years ago. And it seemed that even with those there is a slight play possible. Factory marks are quite rough as I have seen, like on the front sprockets there is no clear mark what would line up with the one on the casing.

It’s a bit of a project, But you can replace the chains with the engine in situ. At least: I do it that way
I thought it's a myth :) Good to hear from someone with first hand experience. Given the available space there I don't doubt it's not an easy task. Already seeing the small pin falling down somewhere behind. I will have a look again how this could be done.
 

chad5k1

New Member
Messages
167
#9
Just do the chains, the engine will be down on power as they stretch. I'm led to believe that you can use the cup timing (or close to it) for greater power on the 2.8. I think this was part of the change that was done to few 2.8 cups from the factory.
 

spacecadet

Junior Member
Messages
242
#10
Mine is a 2.0. The Cup timing would require the suitable EPROM too on these no? How different is it than the standard 2.0 timing? Do you have data for these?

Meanwhile I also realized that I have to remove the engine, because the R.H. longeron is cracked where it's narrowed to let the turbo fit, and I would like it to be repaired properly.