HELP! Fix for contaminated oil system

[chopair]

HELP! Technical assistance please! Fix for contaminated oil system for a Thumper 320/XR250:

This weekend’s rides revealed a number of troubling issues: First was horrendous oil consumption. Next was an oil change that revealed the blackest dirtiest oil that I have ever seen after only about 30 miles, and finally upon removal of the oil filter screen from the bottom of the frame revealed that it was nearly completely filled with abrasive compound and metal chips. Inserting my finger into the frame revealed nearly a ¼ inch depth of said abrasive compound/metal mixture. It was clear that the entire oil system and engine was contaminated. The bike in question had recently had the frame powder coated bright red. The first step of this process is to glass bead blast away the old paint. The frame holes were obviously not plugged adequately to prevent this material from entering the oil fill hole and or other entry points. The previous owner flushed the system by changing the oil 4 times and running the bike between changes. I am sure that this method did remove some of the abrasive compound, while distributing the rest through every component of the engine and lubrication system. The problem is severe. I can’t really imagine a better way to sabotage a motorcycle… Unbelievably, the thing still runs fairly well, except for the fact that it uses a quart of oil in 25 miles!

I need some expert opinions on how to really repair this bike.
What do I have to do to ensure that this contamination is completely gone?

I really like this bike and would like to bring back to a mechanically sound condition,

Thanks for your help,

Chopair

 

[SFO]

The future looks bleak.
There are two ways to go about making your bike right.
#1 is the hard way. Complete disassembly and cleaning and inspection.
Motors don't like sand. It was the #1 reason we didn't sandblast heads when rebuilding them, you can't know for sure they are 100% clean.
I would tear it down to the bottom end because cranks don't like sand either.
I know this sounds extreme but it is the only way to have peace of mind.
#2 sell it before it gets worse.

 

[DualSportr]

<<The previous owner flushed the system by changing the oil 4 times and running the bike between changes.>>

Hate to say it, but I'm with Bill's #2 choice on this one.

We had a YZF426 race bike that suffered the same fate. Engine only ran for about 20 minutes before it started smoking badly and was removed and shipped back to us.

Every part inside had at least .020" to .050" of material removed from it. Not a single piece was salvageable. Keep in mind this was a Four Stroke National engine which had just been blueprinted by our shop. If nothing was worth saving in that $20,000 machine, I don't know how many bits inside the XR250 will be worth more than a paperweight.

BTW, if you do tear into the engine, make sure you have a good idea of correct clearance specifications - since everything will look beautifully machined with perfectly beveled edges - it'll all just be waaaaaaaay out of tolerance.

 

[chopair]

I would love to sell this bike. Unfortunately it was purchased from an industry technician who assured me the problem was handled. I liked the guy and I trusted his estimation of the situation. Now, However, I am faced with the dilemma, repair of sell. The bike, from the outside, is a showpiece and I paid accordingly. Hindsight certainly indicates I should have been far more probing regarding exactly what work was done to repair the bike after its bead blasting contamination problem occurred.

How can I sell the thing with good conscious? I cannot assure a new buyer that this bike is OK. Knowing what I know now, any statement like that would be totally dishonest. If I told them the truth, the selling price would be fraction of what I paid. If I do need to get a new/used XR250 motor to rebuild from scratch, do you know where I can find one?

Thanks for your help, it may not be good news, but it sounds like the truth to me.

Flynall

 

[ochster]

Sounds like a good time for the "industry technician" to back up his handiwork/claim. I've been bit, it's never easy, but in the long run I sleep better.