spun rod bearing = metal filings?

[crowesnest3]

so I.ve been on the hunt for an illusive knock, as it seems a lot of us are looking at the number of posts in the 800lb gorilla thread. The question I have is if the knock is from a bad bearing, would that not leave some evidence of metal filings in the oil? Drained mine down again after putting on roughly 750 miles, which included some high rev gear banging. Drained oil out through a lacquer paint filter cone, nothing except some minute brown chunks of ? Also, checked oil filter, new @ 1150 miles ago, nothing. Some small chunks of brown crude in bottom of white bucket I used to collect oil .... dumped oil filter at end not using filter cone ... dragged a magnet around just cuz, nothing. The knocking which seems to be located somewhere near the back of the block , even bought a stethoscope for the tool collection, the knocking is such that it is hard to believe it is not in some way destructive to something, so much so as to at least leave some metal behind. Looking for some opinions ....... Crowe ....... runs strong, got high compression on all 4, carbs syncd, belts changed, valves adjusted, stator nut tight ....... ????????

 

[mcgovern61]

I made my knock go away two different ways.....1st...I turned up the radio real loud :music3: ....2nd..I swapped out the engine! :smilie_happy:

 

[crowesnest3]

so how do you know that the swapped motor doesn't have the plague?

 

[dan filipi]

so how do you know that the swapped motor doesn't have the plague?

That is why I'm building one.

 

[macka]

That is why I'm building one.

Are you doing a stock rebuild or a performance rebuild?

 

[mcgovern61]

so how do you know that the swapped motor doesn't have the plague?

It was an educated guess. :laptop:

My '81 engine had a lot of symptoms that I did not see (It was my first 1100 engine and I had no experience). I learned my 1100 while restoring it and piece by piece it came together. From the beginning, CGW forums were a great help and I learned alot real fast. By the time I decided to do something substantial about my knock, I had tried most of the "cheap" methods of finding the problem short of splitting the case. The critieria for replacing the engine, low mileage below 50k, '82 or '83 for the gearing, and low price (below $100 bucks). At $100 max (I knew shipping would be as much as $300 if I could not find a local engine) I considered the risk worth it. The reality is, the greater part of 1100's on the road do not have knocks and there are 1100's on the road with over 100k miles across the country with no knocks or noises. The risk is actually low of getting a bad engine if it came out of a solid runner.

Bottom line, my '81 engine had over 169k miles on it, it sat for many years before two PO's, the last PO beat the daylights out of it (tried to make it a street racer), someone poured sand into the oil (getting back at PO for something?? He was a college student), the carbs were way out of whack...but it always started right up, ran fine otherwise and I put 7k miles on it with the knocking at high rpm and it never let me down. I am under the opinion the engine should have blown up...but it never did.

 

[dan filipi]

That is why I'm building one.

Are you doing a stock rebuild or a performance rebuild?

I'm taking down 2 complete engines to make one good with all within spec parts.
Hone and new rings, valves lapped, new springs, guides and seals.
I also have internal parts on the shelf and with the help of the good folks here I should be able to put it together and have an 83 engine with good compression and oil pressure and quet primary chain.

 

[crowesnest3]

not that I am looking to do it, but I could see breaking down the engine I have, its only got 26400 on it before picking up a donor. Also, now thinking that I doubt that I will find some "easy" fix like sync the carbs, so in the end I'll have to move beyond my state of denial and pull the motor. In the meantime hope that the "knocker fairy" will come in the middle of the night and fix her and/or keep riding while I've got the weather.....Crowe

 

[dan filipi]

I've been thinking after posting this morning I might rebuild 2 heads then put them on my runner to help source the knock I've been chasing for years.
If I don't do this and the knock is gone after a complete top and bottom end build I'll never know exactly what the cause was.

 

[mcgovern61]

I've been thinking after posting this morning I might rebuild 2 heads then put them on my runner to help source the knock I've been chasing for years.
If I don't do this and the knock is gone after a complete top and bottom end build I'll never know exactly what the cause was.

Rebuilding the heads with new springs and cleaned up valves could be tell tale to this knocking. At least you would have an engine that knocks and each item corrected could be documented before and after and when the knock is stopped (of course that is the goal) it would be useful to see which item did it.

The MC shop I took my heads to listened to the video of my engine and remarked that the high mileage with the visible wear and tear seen on the valves and springs points to worn engine and possible worn lower end by default.

 

[dan filipi]

From what I've found these engines have a very strong bottom end but a not so tough top end and possible piston pins.
I get opinions from shops the cam wear is not bad and actually serviceable, they say put it back in.
One shop said the flat spots on the cam we have suspected being caused by weak valve springs and rocker bounce was "normal" and not something that would cause a knock of any kind.

The only way left as I see it is to rule out each component.

 

[joedrum]

i think there crazy dan .....ive got quite the assortment of cams ...theres no doubt that the 1200 cams witch i have look great one motor had 97000 miles on it the 78-79 cams i have look great too but these cams have the sortest lift and open time of the oldwings early 1000 cams and 1100 cams have the higher lift and duration wit the 1000 75-77 cams the most .....that hammering look comes from hammering period ....metal is hard and dont get like that unless its getting quite the treatment from the rokers ....the 1000 and 1100 motors are already have 5 thousants gap in the valve trane and when te sprngs get weak and the valves are in closed possition they start drum rolling on the valve seats and the cam ...

im in the camp that most of the time somthing gose wrong with the valve trane first and then the belt gose out not the other way around ...that the belt breaks and then the head ....i just have to much evidenced that valve springs are the weakest link in these old motors ....

i have a set of vw springs im going to try that V gave me but my project bike got slamed by the storm and the motor got hit by a huge tree that was maskerading as a limb from a huge red oak :crying: :cheeky: :Awe:

 

[crowesnest3]

......a follow up, dropped the oil again, this time after @ 750 miles which included some high rev gear banging, if its gonna blow its gonna blow, filtered oil thru paint cone again, nada, nothing in oil filter either. Running a Rotella 15/40 with Lucas oil stabilizer added for a little cushion, although I don't even know if this is a bearing or not, no metal. Also, tried the disconnect the plug wire diagnoses suggested by a variety of sources, the theory being that the cylinder with the bad rod bearing or wrist pin will stop knocking when its not firing, The knock - tap at idle - didn't go away! and so whats next? Interestingly, with the heavier oil mix - maybe - everything is pretty quiet cruising between 50 and 65, which is a good thing, but the mystery continues .... Crowe

 

[joedrum]

im in the campthat you probably have piston pin noise ..as they have a sleeve that can war thin and cause noise like a rod bearing ,,,,to me its only thing tat makes since as you are styig on top of everything ....this will not cause a metal shaving ...i think the sleeve is copper...it wouldbe nice to find a parts pic of the piston pin set up fo hs thread :mrgreen:

 

[dan filipi]

...it wouldbe nice to find a parts pic of the piston pin set up fo hs thread :mrgreen:

I can do dat, I happen to have a couple loose piston and rods in the garage.

Be back in a few........

 

[joedrum]

man and rod bearing can go bad and not leave much metal shavings there made to wear not make shaving ....but if you have good oil pressure and its making a rod like noise its most likely a piston pin they can knock forever ....i think that alot of oldwings that have the top end freeze up at speed will cause a prfectly good piston pin to go bad instantly ...ive seen cams break completly into from it theres plenty of torque there to put on a piston pin ....

 

[dan filipi]

This piston gave up it's life for me to take it apart for this post, I don't have the proper tools to press it apart.
Took heat, a socket, and a hammer.

No brass, the piston pin is a press fit into the rod,

The pin is free to rotate and slide back and forth in the piston, there are no retainer clips.

Oil holes,

 

[joedrum]

i just lov this forum ts more like working buddys that are trying toget things done :Egyptian: :Egyptian: :music3: :builder: :ahem:

 

[dan filipi]

Here's an extreme closeup of the piston pin journal after me beating the bejesus out of it with a socket and hammer to get it out,

 

[crowesnest3]

ok, wrist pin. but what would make the sleeve open up? I've only got @26500......to add an interesting note, I put the Rotella 15/40 back in since it only had 750 miles on it, but I mixed in a quart of Lucas oil stabilizer, supposed to help with "worn" engines, this left me with a quart for the shelf for another time, don't burn any oil. The interesting note is that the knock has gotten substantially less in volume, the oil?, the good luck fairy, or she's getting ready to blow ... the lull before the storm......... back to wrist pin, from Dan's pics, which are great, pretty obvious that pin is in there pretty darn good, so again what is it that would make this pin wear enough to knock? ....Crowe