INOA 2017 Norton Rally.

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I got back from the Rally all well with everything except my running shoes, as one fell off somewhere between Pennsylvania and New York State. At the US, Canada boarder I discovered one was missing and I just tossed the other in the trash. No good keeping one shoe. I tied them to the webbing but not good enough. I have some shots on the odometer at the start and at the end of the trail when I parked it in my garage after the return. 1716 miles round trip. I didn’t get the long distance award, as I was less +150 miles from the winner, so good for him. As you see, I don’t bring my bike to show and shine off of a trailer to get a trophy. I like to ride it.

INOA 2017 Norton Rally.

Gas and Breakfast here Northbound on 219 PA
INOA 2017 Norton Rally.


INOA 2017 Norton Rally.


Now to The Bent shifter Award. Pete Turner should have got this one this year but someone who had a Portuguese lay shaft bearing go south, got it.
The event… The Rally picnic ride to Peaks of the Otter on Wednesday was the route. Riding as our own group Canuk’s ONO and New York’s NYNOA decided to hold back from the crowd to drive hard and fast. Somewhere past the 61-mile marker on the Blue Ridge southbound, Pete lost oil pressure, which he recorded on a camera and he tapped on the oil gauge to see if it was stuck. 30 seconds later his Combat engine is not making good sounds. De-clutching and trying to down shift only smoked his tire as the engine was locked up. I was directly behind him. Nothing would move. His Combat was dead to him. Once we got the bike in a safe area, Pete stayed with the bike while Richard and I road back to the camp to get the truck. An hour later we had it strapped down and headed back to the campsite. We placed it in the pavilion in our area campsite and drank some beer meditating. Dynodave came by and we talked an suggested we pop the timing cover tomorrow and have a look see. As a group we were training our thought on the oil pump.
The next day we opened it up and sure enough the oil pump shaft was bent and the worm gear was missing teeth. Disassembly of the oil pump we found hard metal bits embedded in the spur gears. What was the cause? I was thinking as well as some others that one of the combats thrust washer tab on the cam or the hardened cam lifter pads broke away. No one was injured so thanks to that but Pete’s bike needs attention back at a shop.
Today I popped by Pete’s home with some of my Norton tools and we did an exploratory. Here is what we found:

Cylinder is toast and one con rod piston toast.
INOA 2017 Norton Rally.

Spun bearing on Timing side.
INOA 2017 Norton Rally.


Combat timing side. Norton had some bean counters changing the 72 crank case halves Don’t you like the Bean counters. Look at all the beans.
INOA 2017 Norton Rally.


Snapped con rod bolt and what’s left of the shells and connecting rod cap.
INOA 2017 Norton Rally.

INOA 2017 Norton Rally.


My suspect thrust washer is still there so not this one.

INOA 2017 Norton Rally.


INOA 2017 Norton Rally.


The builder chose this cam bush for the inside.

INOA 2017 Norton Rally.


The remains of the timing side connecting rod and piston. Toast.

INOA 2017 Norton Rally.


Drive side con rod ok and shells were ok.

INOA 2017 Norton Rally.


Teeth busted on the Tach drive.

INOA 2017 Norton Rally.


Combat cam has busted teeth on the gear but lobs are ok. Toast.

INOA 2017 Norton Rally.


Lifter Pads look Ok.

INOA 2017 Norton Rally.


Cleaned up cam but too bad for the teeth on the gear.

INOA 2017 Norton Rally.


Here is my suspicion to the cause.

INOA 2017 Norton Rally.


Pete’s now looking for an 850 engine complete preferably 74.

Happy Trails,
Lets hear it :mrgreen:
Cheers,
Thomas
 
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It's most likely that the shrapnel from the failing rod bearing is what locked and broke the oil pump.

It's generally been found that a Norton motor will blow up approximately 15 to 20 miles after the oil pump quits pumping, so it is likely that the bearing failed from something other than the broken oil pump.

I would agree with your final analysis. I see about 1 case a year. Jim
 
You say in the original thread "past the 61 mile marker" how far was that from starting out that morning?
 
Sad yet interesting pix. Not convinced of the anti sump being the culprit, though it is possible. That is based on two of my observation about the oiling on a norton.
1. A good pump can and does completel suck a 4141A tygon hose from vacuum to a full collapse if the feed line is shut via ball valve. Key being "good".
2. 2 NENO members, having full big bux engine rebuilds...(not by me)... had very rapid engine oiling failures (without wet sump check valves).
Later, after the fact, oil pump testing on my rig showed these pumps to be quite poor.

bonus: 2 additional club guys sent me pumps for testing on pumps they would have otherwise just put back in their engine rebuilds. They were in fact 2 of the worst pumps I had ever seen. They bought new ones.

These type of results keep me motivated to improve my testing procedures and continue oil pump research.
 
Tell Pete I've got a spare set of cases, rods, and assorted bottom end bits and fixings (mains, cam etc) if he needs it, all 750 though
 
acadian said:
Tell Pete I've got a spare set of cases, rods, and assorted bottom end bits and fixings (mains, cam etc) if he needs it, all 750 though
Thanks acadian. I'll let him know. :wink:
Cheers,
Thomas
 
dynodave said:
Sad yet interesting pix. Not convinced of the anti sump being the culprit, though it is possible. That is based on two of my observation about the oiling on a norton.
1. A good pump can and does completel suck a 4141A tygon hose from vacuum to a full collapse if the feed line is shut via ball valve. Key being "good".
2. 2 NENO members, having full big bux engine rebuilds...(not by me)... had very rapid engine oiling failures (without wet sump check valves).
Later, after the fact, oil pump testing on my rig showed these pumps to be quite poor.

bonus: 2 additional club guys sent me pumps for testing on pumps they would have otherwise just put back in their engine rebuilds. They were in fact 2 of the worst pumps I had ever seen. They bought new ones.

These type of results keep me motivated to improve my testing procedures and continue oil pump research.
FWIW The crank still had oil in the sludge trap but the timing side journal had completely plugged oil holes from the spun shell bearing. I am surprised that it was the timing side to let go first. Trying to listen to the video a number of times only gave symptoms that something is wrong in the last 30 seconds. Another member of the ONO had, in his haste putting back together his 850 switched his oil lines with similar catastrophic results at our Dark Cafe Rally last year past. The drive side con rod holed the case about 20 min into the road ride.
Cheers,
Thomas
 
comnoz said:
It's most likely that the shrapnel from the failing rod bearing is what locked and broke the oil pump.

It's generally been found that a Norton motor will blow up approximately 15 to 20 miles after the oil pump quits pumping, so it is likely that the bearing failed from something other than the broken oil pump.

I would agree with your final analysis. I see about 1 case a year. Jim

It was about 25 min into the ride. The video was 28 min long.
 
dynodave said:
1. A good pump can and does completel suck a 4141A tygon hose from vacuum to a full collapse if the feed line is shut via ball valve. Key being "good".

Very true if there is no air in the line between the pump and the valve.

Get an air bubble in the line, even with a fresh pump, and the pump will not draw oil through the spring loaded valve.

Of course a worn pump makes it more likely that an air bubble will get into the line. Jim

PS, I have torn down engines that had seriously damaged rod bearings and the engine was running fine with no sign of the impeding doom.
 
A VERY sad story, ugh. As for me ... I would NEVER ever, no NOT ever ... use and inline shutoff valve; too dangerous IMO. (don't ask how I know, ugh) Anyway, as far as marginal oil pumps; how do these Norton gear driven pumps ... get "marginal" ??? For crying out loud, they are bathed in oil, and should never where out IMO. dynoDaves testing proves some a really bad; what am I missing here :shock:
 
nortriubuell said:
A VERY sad story, ugh. As for me ... I would NEVER ever, no NOT ever ... use and inline shutoff valve; too dangerous IMO. (don't ask how I know, ugh) Anyway, as far as marginal oil pumps; how do these Norton gear driven pumps ... get "marginal" ??? For crying out loud, they are bathed in oil, and should never where out IMO. dynoDaves testing proves some a really bad; what am I missing here :shock:

Luckily, I got hit in the head with the "smart" hammer nice and early into my experiment with one of those inline valves, it came apart on the bench while I was attaching the oil lines to it :D
 
NTB
Been doing oil pump examinations for quite fa few years and this is what I have found...
1. New pumps have the gear cutter marks running parallel with the gear faces.

2. As they wear due to ??? very small grit that gets past all oil tanks screens on the feed side and on NON 200000 sump screens. The gear tooth faces seem to eventually burnish away the machining marks and the pattern eventually changes 90 degrees looking like the gears were scoring against each other with coarse lapping compound. finally the gears further gain flat spots mid gear face and start to grow wider and wider. This obviously starts to open the clearance on the back sides between the mating gears. This can not be fixed. 200000+ pumps tend to die even faster than all other NHT.

3. Between the tips of the gears and the iron body... grit acts to wear open the "as new" close tolerance. This opening tolerance allows back slip of the fluid and less volume and lower pressure result. Death by a million cuts/scratches is how this progresses and can not be fixed.

4. shaft to body wear is another wear and oil escape path. To o-ring the two shafts can provide some relief from this symptom.

5. The end wear of the gears against the iron body or brass end plate on the feed side, or iron shaft holder on the scavenge side, can slowly open up the clearance again allowing more back slip of the fluid. This is the only area that is addressed by the factory service manual "reconditioning". It is a glorified band aid that does improve this one aspect only, though I feel it is way over sold as a "cure".

Thomas
I see the crank was split. I would have been incredibly interested to see the sludge trap grit and grime washed out on white lab filter paper. :twisted:
 
dynodave said:
Thomas
I see the crank was split. I would have been incredibly interested to see the sludge trap grit and grime washed out on white lab filter paper. :twisted:
dd
I found particles in the timing side from the spun bearing. no sludge as the engine was re-built after Pete had a drive side case crack at the 2012 end of the world Vermont rally caused by a missing lower transmission bolt. He has had some bad luck but he did have a strong combat. I had to really put on the coal to keep up with him on my 850 :wink: He had the smaller ports on the head not the 32MM. It pulled like a train.
Cheers,
T
 
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