Ghibli engine knock, timing, rebuilding.

First post, here, greetings from Holland!
Very intersting topic this one indeed.
So, to be sure i understand correctly: You had a bad rod bearing in your first engine, that was already exchanged once.
Then the "new" engine came up with the same problem after 1000 miles.
This sounds like a serious Ghibli problem then!
Or where metal shavings left behind in the oil/water-heat exchanger, that was re-installed every time maybe?
I am very eager to learn about the real cause of this bearing problem.
When i look at the main bearing shell, everything points at oil contamination due to metal particles.
Even an overdue oil filter should keep this out, until it is really clogged and oil pressure goes down.
In that case, normally a by pass valve would open and yes....unfiltered oil is passed.
And am i right in reading that the Jeep 3.6 oil pump, fits the Ghibli engine?
Some speak about oil pump problems, does Jeep also know these problems?
Glad to hear your thoughts about this!

Yes, you have that correct! This is at least the 4th engine/rebuild going in just this car.
1) Original engine.
2) Salvage engine in car w/rod knock when I purchased.
3) Salvage engine I purchased to put in the car.
4) My rebuild on the salvage engine.

The oil cooler is actually in the "v' of the block below the intake manifold and fuel rails. So this is something that would likely stay with each engine and not be transferred. The used engine (boat anchor) i purchased came with the manifold on it with a "warranty void if removed" sticker. Warranty was only 30 days. I put a brand new Maserati oil filter and oil when i put this in. I wish I would have checked the valleys of the old oil filter when i removed it. The only oil related part that was reused was the turbo chargers which of course I flushed thoroughly. Even then, the particles would be going into the oil pan/filter.

Yes I used the Jeep 3.6 oil pump. I am glad I could find one made by an aftermarket just incase there is an actual issue. I absolutely hate the design of this pump. Some sort of 2 stage deal with blades that shift outwards with centrifugal force. Wish I had taken a picture. I've never seen one like this in an engine I built but may just be a newer design. Also something that bothered me was the design of the oil pick up tube. 1) It's plastic. 2) the diameter seems excessive perhaps cutting down velocity/suction pressure. 3) the oil pump screen is being located at the top end of the oil pan rather than at the bottom as i'm used to. It is also in a large cavity more than halfway up the tube. It just seems like a recipe for disaster to me. Easy to get an air bubble. Or if the plastic tube cracks and you can't get proper suction.... In my opinion I think some more conventional thinking would be beneficial. I looked into the jeep 3.6 oil pump because i haded it so much but could not use it because the deep part of the sump must be at the rear of the engine instead of the front like ours.... which again might be another small issue.

Think of this with the average joe: the oil change interval is what every 12,000 miles? ok, guarantee most people driving these cars don't check the oil and probably expect the car to check it for them. 12,000 miles on oil in a twin turbo engine a lot can happen. The oil running through hot turbos certainly degrades the film strength (yes i know they are "cooled") but that will still be more abuse than a standard naturally aspirated engine. The ring gap it typically wider on turbo application allowing more blowby and oil to be burned. So after 12k miles you probably lose at LEAST a quart but i would guess 2. Then you're at 11,999 miles on the last oil change, your film strength is degraded, you're 2 quarts low, you floor it and all the oil you have goes to the rear of the engine where the pickup tube ISN'T next thing you know you could be sucking air at a time when you need maximum oil film strength, and luck just to keep from grenading the engine normally.

Oh and put all that on top of the fact that the main bearing was tapered on this crank and presto metal on metal contact. Which I believe would cause a loading/support issue at any rpm. There is a reason they have taper limits I'm sure of it.

Keep your oil topped off and change it every 5k I would suggest.

I'm not sure if jeep is having this problem but they also did have the oil pump in stock... so that must be some sort of indication of demand.

I have over 1,000 miles on this rebuild so far and still going strong. I have changed the oil twice, and been through 10 oil filters just checking for metal particles so often. So far so good.

I would like to say I've had really good luck with oil filters. I once took an oil pan off a mitsubishi I turbocharged and did some grinding in the crankcase. Cleaned up what I could but I'm sure i didn't get it all. Also had a oil return come off on the highway lost all oil with that same engine and made it to a parts store parking lot. Still ran for over a year without issue 10k+ miles before I sold it and i bet it's still going.

Do you know what kind of oil was in your "rod throwing" engine?
Maybe it was a 10W60, it will cover up some leakage though worn bearings.
I also think that the oil pump has quite some capacity, as it is capable to achieve end of scale pressure with relatively low viscosity oils even in hot conditions at quite lowish engine rpms.
This makes it difficult indeed, to know when things become bad, just by observing the oil pressure meter.
To be honest, i am afraid not all dealers change the oil filter, everytime they should.
I am almost 100% sure, the filter in my car, was the one it came with from new.
Some mechanics even say that changing the oil filter at every oil change, is not that neccesairy......yeah, right.
And if they don't, will it still be mentioned on the invoice....what do you think
( i have seen and heard some sh#t)
Also, do these cars always get the correct type of oil at the correct intervals?
Of course, there are very good and trustworthy workshops and mechanics also.
If you have one, be happy!
Just out of interest; the bearing shells, are those multi layer (babbit) ones, or metal/aluminium?

I'm not sure what oil was used in the engine that was knocking when I got the car, but I do know I put a brand new Maserati oil filter and 5w-40 mobil 1 in the used engine I purchased that threw a rod bearing. I've never seen 10w60 on a shelf in the US so I would surprised if that was the case.

Based on the clearances of this engine I imagine it could run on 5w30 no problem, maybe even lighter weight oil. I feel like too heavy of an oil can make for a risk on startup if it doesn't have the proper clearance to circulate. If you look up the jeep 3.6 which is in my opinion the base version of this engine it runs on recommended 5w20.

I would not be surprised if techs were not changing the filter, especially on these cars, it makes a huge mess. This is why I always do my own work, just can't trust anyone. I used to work at a shop that had virtually no training to the employees, just learn on the fly lol.

The bearing material was multi layer. Babbit, copper, and steel backing from what I saw. This is good in my opinion and really a must have for a performance engine. Steel backed bearings can withstand much more pressure than aluminum and should always be used in performance application in my opinion.

I believe another "unseen" factor could be effecting these engines. Engine balance. If I were to do another one it would interesting to see how far off balance the original assembly is. At 6k+ rpms and high cylinder pressures from turbo, this thing could be throwing serious pounds of force if not properly balanced. I believe this is the first high volume productions of engines from Maserati and perhaps it is one of those items that is "close enough" and not dialed in by hand on each engine.

BGeorge said:

If you’re talking about the crank pulley bolt it is 1-1/4 socket. If you are talking about the bearing main caps I believe they are 15mm & 13mm.

Click to expand...

Were you able to figure out what caused the failure on your Motors? I had 2 motors that threw rod bearings and my guess is that the oil pickup tube is the one that is faulty. I didn't see anything wrong with the oil pump but noticed the oil pickup tube wasn't sealing very tight. My guess is that this caused the pump to suck in air and thus causing low oil pressure and not lubricating the bearings properly. I also noticed that in the newer model oil pumps, the oil pickup tube had reinforcements on the plastic while the earlier models did not. And based on the forums it seems like 2018+ Ghiblis don't have as many oil pump failures as the 14-17 Models. Pictures of the oil pumps attached for reference.

2014 Pump no Plastic Reinforcements



2018 Oil Pump