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Ghibli engine knock, timing, rebuilding.

3071 Views 46 Replies 8 Participants Last post by  Burner67
I would like to share my learning experience on this engine with people who may be interested in some deeper insight or answers.

Backstory: I purchased my 2014 Ghibli SQ4 with a known bad engine (rod knock). Upon removing the engine I found it was already a used replacement since it had salvage yard markings. I tore it down and it was just too far gone. Multiple spun rod bearings and spun mains along with grooved cylinder walls. Our local machine shop didn’t have the tooling for line bore and at that time I had no leads on over size bearings or pistons. So I purchased a used engine. After installing I only received just over 1k miles before it too lost a rod bearing (should have checked filter before install). I was able to save this engine and rebuild the bottom end.

During the rebuild process I did find a few notable items. I read a lot about oil pump failures on these engines but don’t think that was my case. The oil pressure was fine on this engine. In fact I was planning on cleaning and reusing the pump because of the price. It was only after I found an affordable replacement from melling did I decide to replace it. M-528 was the model I used from the jeep 3.6. Autozone had it in stock as well as the timing chains. While I was tearing the engine down I notice it was the #1 rod that lost the bearing. I also found the #1 main bearing was nearly gone as well. It looked like it had been scoring for quite some time. As far as what caused the failure, the only sure thing I could find wrong was that the #1 main journal on the crank was tapered. Clearance was .002 tapered down to .001 or so on the tight end. I even flipped the crank 180 and put the last journal in there to make sure it wasn’t the block. It was the crank.
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Timing- it took a few tries and some research but eventually I nailed it after finding a couple repair manual pages. I highly recommend purchasing the alignment tool as there is no crankshaft timing mark and you will want the plates to hold the cams while you’re making fine adjustments. There really is also some sort of a mystery here. When I took the engine apart I never removed the cam gears or even touched the bolts. So I didn’t think much of them when trying to time it. So I put it together once before I had the timing tool and just lined up all the marks with the chainlinks etc. started it up, drove around. Got timing codes. So I ordered the tool, took it apart and retimed it. Once I had it
running again it threw the same codes. Took it apart AGAIN and finally found the key. You have to have 12 chain pins between the timing marks on the cams up top. The only way I could achieve this was by loosening the cam gears and turning them just slightly to fit one more tooth over. That is what solved it. Keep in mind that I never touched the gears until that time so I’m not sure how they could be a tooth off. All the cams were labeled and installed where they originally came out.

I’ve Attached some images for reference. Hopefully this has been insightful. I wish I had more pictures but after continuing issues I was never sure what was going to be right or wrong.

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Yeah no CEL. Oil pressure always good. Just love tearing into this thing haha. Seems I could hear something from the oil fill hole at idle. Could not get it to happen on cold start. Only when warm. Can’t hear anything when turning it over by hand with plugs out. Would really expect a CEL if something in the timing system. Engine is very sensitive. Hope to find something..
Did you check the main bearing shells allso?
And how was the shell supporting surface of the rod?
Did it not suffer any damage from the spun shells?
Main bearings shells are good as well as the thrust bearing, and rods. The rod with the spun bearing was replaced when put back together. I haven’t had a whole lot of time to work on it lately but the engine is out and all covers are off. The only places I can seem to create any noise or looseness is with the driver side upper timing chain tensioner and the crankshaft end play. I have a tensioner ordered. Given the the thrust bearings are in tact and not scored I doubt that’s the issue. Curious to see about the new tensioner. I don’t really believe that is it but you never know.
And how was the shell supporting surface of the rod?
Did it not suffer any damage from the spun shells?
I checked Main Bearings on my 16 SQ4 and they were all good. I did not replace them as they showed little to no wear. My only issue was one, spun rod bearing that caused the engine to lock up. The remaining rod bearings were fine but I ended up replacing all the rod bearings but kept the original crank bearings. As for the shells, no wear on the main bearing shells or the connecting rods/caps. Only visible wear was on the crankshaft of the rod bearing that spun. I ended up polishing and sanding down all the scoring on the crankshaft. I used the original oil pump but changed the tensioner and the O ring on the suction tube.
Hi guys, I'm also on the path to rebuild the engine of my Ghibli as result of 2 spun main bearings and 4 spun rods... I found 0.25 and 0.50 oversize bearings and my machine shop confirmed that we can save the block and the crankshaft. The biggest concern right now is that we can't find any technical data of the engine, I search everywhere for m156b or f160 data, but there isn't any.
Can someone suggest a source for it? I need the crankshaft and block specs and on later stage the chain timing.
You are going to have a tough time finding any of that for this engine. As far as clearance goes I don't see why the machine shop could not figure things out with what they have. Measuring the good rod and main journals for size and the good bearings for size. Or perhaps after receiving the new bearings they can measure and determine the machining they need done. As far as torque specs go you may find some things here and there. I'm sure a lot of these bolts are carried over from the Chrysler 3.6 like many other parts. That's what I went off of. You will want to purchase the timing tool to set the timing and reference my first post on this thread about the chain link count.

On another note I'm still chasing down this knock noise. Engine is back in the car been driving it but just still has that knock when revving and letting off the gas around 2500 rpm. The timing chain tensioner didn't take care of it. It's definitely coming from the front of the engine. It sounds very similar to a loose or cracked flex plate but its coming from the front. Can't wait to get this one figured out.
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