Engine failure, root cause?

[1784]

I recently adopted a D1 -96 3,9 that was stuck at the dealer with the doom "needs a new engine". Since it was much better shape in frame, body and interior than my -95 I thought it was worth looking into what was the situation with the engine.

I have now removed the engine and are taking it apart. Found this tonight, let me know what you think has happned. What I know is that it went to dealer to get a new oilpump installed about a year ago.

Looking at rockers they are all fine, as well as pushrods. Cam looks OK from valley, but I will take the heads off now and see how the valves and piston heads look like.

Thanks!

 

[mbrummal]

looks like that that washer or gasket whatever fucked that timing chain/camshaft gear.

 

[1MITCH1]

X2

 

[Jagfixer]

It's a shame that this happens. I've worked with techs that would leave lock washers out to save time. It's disturbing to trust someone and a stray washer wasn't searched for before replacing and closing up.

 

[1784]

Thanks!

So it would be possible for such a small part to break the rather substantial chain?

Does anyone know where that washer is supposed to be located if it had been put in the correct place? It seems to have a quite distinct shape?

 

[Bosbefok]

Someone dropped a locking washer and did not retrieve it IMO.

 

[lforgue8]

Someone dropped a locking washer and did not retrieve it IMO.

I WOULD THINK THE ENGINE WOULD BE FINE......SWAP OUT THE CHAIN AND SPROCKETS WITH SOME GOOD ONES AND TEST THE COMPRESSION.....THE WASHER DOESNT LOOK FAMILIAR TO ME THOUGH......TRYING TO THINK WHERE THAT WOULD GO ON THE ENGINE AND CANT THINK OF WHERE THAT WOULD GO....MAY BE FROM THE GUYS TOOLBOX AND GOT DROPPED IN THERE

 

[mbrummal]

The washer might be a part of the distributor. Just a thought. I'm not sure it it has anything like that or not.

I WOULD THINK THE ENGINE WOULD BE FINE......SWAP OUT THE CHAIN AND SPROCKETS WITH SOME GOOD ONES AND TEST THE COMPRESSION.....THE WASHER DOESNT LOOK FAMILIAR TO ME THOUGH......TRYING TO THINK WHERE THAT WOULD GO ON THE ENGINE AND CANT THINK OF WHERE THAT WOULD GO....MAY BE FROM THE GUYS TOOLBOX AND GOT DROPPED IN THERE

The rover V8 is an interference engine. If the crankshaft moved after the timing chain broke There are damaged parts in the valvetrain. If the pushrods and rocker arms weren't messed up it bet a number of the valves were bent.

 

[ptschram]

The washer goes betwwen the drive gear and the body of the distributor.

Was the distributor intact? I wonder if the roll pin didn't shear an the distributor drive gear jammed things up, the crank continued to turn and the gear was the weakest point.

If the engine was cranked with it in that condition, I'm willing to bet you have bent valves, bent pushrods, and/or broken rocker arms.

You say it's a '96... Where are you? That's likely not an NAS engine/truck.

I have most of the parts you need to put the front end of that engine together.

 

[1784]

Thanks PT!

Embarrasing enough I had forgotten about the distributor, it was sitting in a box i the back of the Disco (since it was removed by the dealer). I picked it up and as you can see in the pictures, the washer belongs to it. It seems plausible that the broken distributor gear dropped down and caused the gear and chain to break?
What could cause the distributor shaft to break like that?

I called the previous owner to get some details and he claims he turned the engine off at home (all seemed ok). After that it just would not start anymore and was towed off to dealer.

Yes, it's a -96 but as all D1's in Europe it's a 14CUX, not GEMS. It has covered around 110k miles.

Removed the heads and found marks in piston heads and on a few valves, see pictures. No damage to rockers can be seen.
I would guess the pistons should be ok? Question is if the valves are bent and needs to be replaced?

The front camshaft bearing shows wear from the groove in the shaft, is this unusual and in need of attention?

I'm not really sure on how to proceed, if I should do a "full" overhaul with new main/big end bearings, camshaft, rockers, pushrods, tappets, rings and leave the heads to a shop for valvejob and skimming.

OR

Just order a new timing kit, a new distributor, some gaskets and give it a try.

OR

Somewhere between...


Any advice much appreciated!

(More pictures in next post)

 

[1784]

Just added three more pictures

 

[mbrummal]

are the valves seating all the way? is there a gap between the valve seat and any part of the valve?

 

[1784]

No obvious gaps between valves and seats, but I'll have to clean the valve area up and do a more thorough inspection.

 

[1784]

OK, cleaned up the heads and valves, put a strong torch in the inlet and exhaust passages but could not see any seeping light when the valves were closed.
Looked at main and big end bearings but they seem fine, no visible copper anyway.
A few of the camshaft lobes seems slightly worn, so I'm now thinking new cam, lifters and to get a workshop to do the heads, but leave the bottom end as is.

 

[ptschram]

The best way to check valves at home is to pour gasoline or diesel fuel into the combustion chambers and look for bubbles or leakage.

 

[lforgue8]

had not thought of the dizzy washer!!......seems weird that the dizzy shaft broke first though no?

if the valves had contact marks im willing to bet they are bent....a machine shop should be able to tell...or take them out and try to roll them on a flat bench and you will see if they are bent for sure......

now how did that shaft break is my question.....does the engine rotate smooth? no bent pushrods? check the rocker arms are they smooth moving on their shaft?

 

[ptschram]

Judging from the picture, there was a moment where the shaft seized and the gear continued to turn until the shaft broke off.

Poor lubrication perhaps? I'd expect to see the inside of the engine in worse shape with more sludge, but it looks pretty clean.

 

[1784]

I'm also confused about why the shaft broke??
The oil inside the camshaft channel and spacer leading oil to the distributor drive gear smelt very bad which made me wonder if oil flow to the distributor drive had been restricted, but I could not see anything actually wrong or blocked.
Engine seems to rotate smoothly both crank, pistons and cam. I'll take the rocker assembly apart too clean up and check for wear now.
Then the heads with valves will go to a shop for a proper check of valves, seats and if they are "flat" (not sure about the correct eglish phrase)

 

[ptschram]

The only thing I could see would be lack of lube. There is nothing in the top end of the distributor that is strong enough to cause the shaft to break were it to become fouled.

 

[ptschram]

Thinking even more, I'm surprised the distributor didn't turn in the front cover until it hit something and broke the vac advance off.