things that rattle and bang, aka bottom end failure! (2010)

Wilco
Its time to pack up the remains of your motor and take it to an expert [engineer] who will be able to measure and cracktest your remaining parts and advise you what is usable and what is not, I have previously in this discussion recomended Barry linch of Beaumont Engineering, a person i have knowen used and trusted for over 30 years, He specializes in Classic Motorcycle Engines, don't leave it till the last minute as his expertise is highly sort after.

The shell, superior side connecting rod, had she a hole ?

Wilco said:

The big shells are egg shaped, the rod has gouged on the cases and bent, and the piston has hit the flywheel. this is on the timing side, the primary side is completely untouched and does not even show signs of excessive wear.
The barrels are not scored or worn.
The cam lobes on the primary side are worn excessively but I think they have nothing to do with the above damage. It does explain though the top end clatter that it always had.
Diagnosis anyone?

Q1. I assume I should replace both rods and both pistons and not just the damaged ones?

Q2. There is visually no damage to the cases but will they be ok?

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I was thinking how best to describe how lucky you were and decided the proper term is “flucky”. You were very flucky. The one rod began to wrap around the journal and looks like it may have begun to kiss the cam shaft or something else.

Was it a good runner up until that point? Are the signatures on the piston crowns decent and near identical? Are you using an anti wet sump valve which are apparently notorious for starving oil feed?

While gathering new parts I would certainly focus on the cause of this failure. Look at all the clues and recall conditions as you dismantled. Were con rod nuts tight? What was the condition of the lip seal at the end of the crank in the timing cover? Were there any pinched oil lines? Was the oil tank full or empty when you shut it down for the last time?

You do realise this is from 8 years ago guys ?

And I wonder if the remains of that motor are still under a bench somewhere?
There is a 1200 r owner Wilco on the Triumphrat forum. Maybe he threw in the towel and went new/old?

Glen

Yes I understand, but according to his comment do you think that the superior shell had the hole of lubrication?
We cannot see it on the photos and it looks like there is not?

Fanfan26 said:

Yes I understand, but according to his comment do you think that the superior shell had the hole of lubrication?
We cannot see it on the photos and it looks like there is not?

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The hole in the shells is to oil to escape and lube / cool the pistons, it’s not there to allow oil to the big end. Engines can run just as well with or without this hole, it’s not related to the failure.

I understand better why on mine, I squeezed the left piston by strong heat (36 °) in mountain, a very very bad engineer put 2 shells without holes on the left connecting rod and the 2 others with holes on the right connecting rod

On the part-list there his the hole for the supériors shells.

Thanks you Eddie

Sorry to here you had this happen.

your quote.
""""""Also, the wet sumping of the engine has been getting progressively worse this year, to the point where there is so much oil I couldnt even kick it over. My procedure had become one of draining the oil into a clean container and tipping it back in the oil tank. The last time I did this, I saw lots of metal shavings in the bottom of the container. Perhaps this, combined with the wear in the pump indicates some excesssive wear and tear going on inside the motor?"""""""

You were lucky when you saw this. You were unlucky when you ignored the signs.

The same thing happened to me except i never saw metal in my oil, but stopped riding as soon as I heard a noise. I saved my rods . cost me a set of big end bearings and big end bolts.

In your case, the engine would have run out of oil at some stage and worn the big end shells. The extra clearance would then have set up a vibration which caused the big end nuts to come loose. That was the time to turn the engine off when the noise FIRST started. You are probably lucky to not have thrown a rod through your crank case.
Just noticed the comment about being 8 years ago. oh well. Might be a wasted comment.

Dereck

Wilco said:

snipped Also, the wet sumping of the engine has been getting progressively worse this year, to the point where there is so much oil I couldnt even kick it over. My procedure had become one of draining the oil into a clean container and tipping it back in the oil tank. The last time I did this, I saw lots of metal shavings in the bottom of the container. Perhaps this, combined with the wear in the pump indicates some excessive wear and tear going on inside the motor?

Click to expand...

Alas! Those silver shavings were your warning that it's time to tear down the engine, or at least to pull the timing cover off, to see if you could find the problem there.

He had only gone a few kilometers down the road after an oil change before disaster struck. If there was air at the oil pump as in "not primed" that's about the right distance before clang clang.
We may never know. Earth to Wilco.......come in.......over.

Send a few weeks looking up past reports on Norton D rods or prior non D's to see they hardly ever fail 1st and the pictures testify to this as rod and cap and fasteners survived very harsh bending and impact forces w/o failure or would be broken with rod cap distorted and a fastener fractured/bent. The damage patterns implies a sezure of rising piston off BDC. May never know why this happened as piston ring area and bores should show evidence of sticking but apparently don't, ugh.

As stated essentially whole engine is now suspect-injured from case distortions or bearing bores to bent crank and and cam impacting piston/rods. I leaned hard way never re-use rod bolts after a seizure or if over 20 yrs old as corrosion through microscopic suface crack can work along metal grains to snap w/o any high throttle or rpm use. Seizures put a lot of snag=jerk loads on cam drive components too like the whimpy pinon gear shaft case seating.

Going back mostly stock, I'd guesimate, $1000-ish for crank repair/replacement, ~$600 for rods/pistons assembly, ~$300 if cam damaged, plus ~$1000 more for nick nacks and machinist processing/shipping parts to fit nice.

I use Canada based Ed's "Offset Crankshafts" or California Crankshafts that specialize in huge engines but owner is Norton crank familiar restorer for very reasonable cost/time option.
http://www.offsetcrank.com/stroker_why.html
http://www.marinecrankshaftinc.com/

Yet another reminder this thread is from 2010.