Amsoil AMF 10w-40 1986 Honda Magna V65

[Rat407]

1986 Honda Magna
Total miles 23,000
Miles on oil 3,000
AMSOIL AMF 10W-40
Oil filter SMF102
Air filter K&N
Sample date 6/22/06
A friends Honda. I wanted to see what the UOA was since it had a bad rod bearing.Oil was in motorcycle for three months. Bike started to develop a knock, tore down engine and found rod bearing failed. Prior to this the bikes stator was very weak, it was replaced two days before the rod knock showed up. Bike ran strong otherwise. Picked up used and only was able to put this mileage on it since it was purchased. No existing problems where known when purchased. This sample was around town and one 6hour trip to the NC Mountains to Deal’s Gap and back. The bike is water cooled.

Aluminum..........29
Chromium..........2
Iron..............45
Copper............65
Lead..............44
Tin................3
Molybdenum.......14
Nickel............1
Manganese.........0
Silver............0
Titanium…………….....0
Potassium.........4
Boron.............6
Silicon...........10
Sodium.............4
Calcium......... 3501
Magnesium.......20
Phosphorus......1063
Zinc............1313
Barium...........0
Viscosity…………...64.9
Flashpoint F….….365
Fuel%............0.5
Coolant%………......0.0
Water%……………......0.0
Insolubles%......0.2
TBN/TAN…………......7.6

 

[craigq]

So this is what a bad rod bearing looks like

Thanks for posting this !

 

[nicrfe1370]

Yeah, what craig said. It's good to see a report of some major engine problem, so we can have an idea what to look for, or to know what these numbers might mean. What I am surprised to see is aluminum and iron so high. There was a time not too long ago I had a discussion with another member in the gas engine UOA section about what wear numbers are acceptable and what is an alarm level. He quoted some articles that Bob had on his website that anything below 100 ppm was normal or acceptable. It was my opinion then, and is even more so now, that 100 ppm is catastrophic, and this report above shows us that 30 or 40 is definitely a warning sign.

 

[sunruh]

having a baseline of a known good engine gives you the ability to see when it has gone bad.
Al of 29 is kind of high, but why?
Fe, Cu, Pb are also up, but is this all they go up for a bad rod bearing?

got any pics of the bearing to show us how bad it was?

thanks!!!

 

[TooSlick]

I'd guess the Fe is scoring of the crank journal for that particular piston and the Al may be piston scuffing on the cylinder wall.

This failure was caught early...you could see hundreds of ppm if things really came apart and the chunks circulated throughout the engine.

On the plus side, the oil's in excellent shape after 3k.

TS

 

[IslaVistaMan]

The higher iron content could have also been caused by scavenging of iron deposited from earlier wear problems which this engine is known for.

Honda V4s have a problem with the cam lobes developing pits and other wear due to operating constraints and poor oiling.

You don't say what oil was run in the bike before the AMF, but if it was a standard PCMO petro, part of the answer is likely there.

Once you get the re-build done, the MCV 10W-40 would be a better choice, although in this case the AMF did indeed hold up very well.

 

[Rat407]

Here is a picture of the bearing and the rod.

 

[sunruh]

THANKS! for the pics.

see the bearings look that bad and yet the uoa looks that good.

 

[TooSlick]

sunruh,

Spectrographic analysis only picks up particles < 10 um, along with dissolved metallic ions. Most of the bigger stuff from this failure ended up in the oil filter and was not accounted for in the analysis.

Something to keep in mind and why aircraft owners cut open their used oil filters for inspection!

TS

 

[RinconVTR]

23k and the rod bearings failed? Whats the history of this bike?

 

[F15Ejetmac]

I am the owner of this bike. The bikes history is as follows, I am the second owner, first owner had regular maintenance done on bike but did not ride it much (obviously) There is nothing to report from the maintenance history, no problems.
The reason the rod bearings went out on this bike was due to a stuck open oil pressure relief valve. It felt like sand to me. I don’t know how it got in, but I know it was not from me.
I have re-built the engine and I have almost put 3K on it. I will burn another sample to base line this motor once I reach 3K