HarleyTechTalk

So I was out riding around, minding my own business, and blowing the cobbs out of the Sporty (bikes are not getting ridden much due to this covid thing). Came back home, parked in the garage. Next morning, it looks like this:

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Before now, was not leaking a drop. (OK, I'll say it: FOR AN IRONHEAD!      )

I did some snooping around, thought maybe a cracked or torn oil line or fitting? Nope. Wet sumping and overflowing out the motor somewhere? Nope. But I did finally find the culprit.

Any guesses?

-JW

Kicker shaft Oring?   

Drain Plug Issue?

Hint: when I replaced the 23T trans sprocket for a 22T, I had to get a different chain. An O-ring chain this time...

-JW

Oil Seal, and/or Retaining Ring behind the Sprocket?

All good guesses. But the key to this riddle was "O-ring chain". As in, wider than a stock plain chain. Also, this bike is lowered. It all added up to the chain contacting the inside bottom seam of the oil tank, and eventually gnawed it's way through.

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The cheap-o fix is to grind it back a bit, then MIG it. But rather rely on an oil tight weld seam, considering my "get to weld once every three months if I'm lucky" welding skills, I think I'll also take it to the radiator shop, have it cleaned out and Red Kote it. Need to check on what the max temp is for that, though.

One other thing, while I have it down for repair. The oil that came out of this thing was jet-freakin'-black. Like what you see come out of a diesel engine. There's not that many miles on it, really, so what's with that? I tuned it a while back with an AFR, and I know it ain't running overly rich. The plugs look great. So..... heat? Maybe time for an oil cooler?

-JW

Ouch!  Nice catch, and Good Luck with the fix.
Over the years I had a 67' XLCH, a 74' XLH, and a 77' XLCH.  Still have the 77'.  My oil always looked pretty nasty on all of them.  With, and without an oil cooler on them.  I just changed it regularly...more than really required.  I haven't ridden the 77' in awhile, started it up a few times.  I can imagine how that's gonna' look.  They were all reliable, and ran great though.

I find that in general, with all things Harley-Davidson, reliability problems are more often than not due to the owner thinking he he can outsmart the factory engineers.


Such is the case here....


-JW

Had the same problem with my 78 Sporty years ago...didn't want to weld due to paint damage (75th Anniversary) so I mixed some j b weld and still good (30 + yrs)...

If you really want clean oil you need a clean oil tank. The tank needs to be removed in order to properly clean the sludge/gunk that stays trapped on the bottom and walls.Salty

OK, so I removed the tank, ground the seam back, then re-welded it. Then using some washers as spacers, offset the tank about 1/8 inch outboard to give it some more clearance from the chain. Yes, I can now count on an nice oil spot on the back side of my upper right pant leg, but no more chain contact with the oil tank. But none of this explains why the oil gets jet black in short order. It's not left over crap in the tank. I cleaned the tank spic and span with kerosene and simple green before welding on it. This black crap has to be coming from somewhere, maybe the cast iron from the cylinders?

-JW

Black soot is a byproduct of combustion and will discolor oil sort of like a dye.Soot is soft and particles are small so they pass thru oil filters and will settle in low pockets of the engine and bag.We never really get all old oil out.Synthetic oil additives also darken with heat adding to the dark color.The good news is that it is not detrimental to the engine.Salty

JW, send a sample of oil out to be analyzed when you first see it change color to dark. Then a second sample when you change the oil next. Comparing their reports will help you determine the cause, and if it's causing any oil life issues.

I've used Blackstone for many years and get great service, and great report analysis. One thing, living in Cali, I'd ship the sample container it in a brown box, and not their container with a label on it. Even though it's legal by USPS standards, some folks at the post office like to set "their" new rules when they see something like this.


https://www.blackstone-labs.com/products/free-test-kits/

That is a fabulous idea! I just sent for the test kit.

thanks!

-JW

 carb maybe rich smell the oil may stink of gas. Just a thought 

I'm thinking probably not. I tuned it with a Daytona Sensors WEGO III AFR with wide band O2. It's dialed in to as close to perfection as I could get with a CV carb.

-JW