Cleaning layshaft passages

[stownsen914]

As part of rebuilding my engine this winter, I'm cleaning out the layshaft and can't get the debris to stop coming out. I pulled the plug in the end and tried running it on a filtered parts washer for a few hours, plugging up the holes and soaking it with clean mineral spirits, and spraying brake cleaner in there. Debris is still coming out. Most is non-magnetic, but some of it reacts to a magnet. The inner passage appears clean when I look, so I suspect the debris is coming from the blind recess the runs circumferentially in the middle of the layshaft, where a pipe cleaner cannot reach. Is there a trick to cleaning this? Thanks.

[Walt Fricke]

Wow!
Shop air through the usual rubber tipped "gun"? Combine that with a solvent. Keep repeating until clean?

One would suspect all the oiling passages in this engine had a lot of bad stuff in them. Did they? Engine have a history of blowing up or bearings failing? The ISs from my several blown up engines haven't had this issue.

About that blind recess - how was that created? Very small boring bar with an expandable tip run in there? I didn't know such an area existed.

[boyt911sc]

Originally Posted by stownsen914

As part of rebuilding my engine this winter, I'm cleaning out the layshaft and can't get the debris to stop coming out. I pulled the plug in the end and tried running it on a filtered parts washer for a few hours, plugging up the holes and soaking it with clean mineral spirits, and spraying brake cleaner in there. Debris is still coming out. Most is non-magnetic, but some of it reacts to a magnet. The inner passage appears clean when I look, so I suspect the debris is coming from the blind recess the runs circumferentially in the middle of the layshaft, where a pipe cleaner cannot reach. Is there a trick to cleaning this? Thanks.

Stowsend,

Do you have any picture to share with us? I’m having a little problem visualizing it and a picture will help an aging mind like me. Thanks.

Tony

[stownsen914]

Well, I looked again more closely. There's no blind circumferential passage - I think it's just a small change in ID partway down the passage. I think maybe the debris is just some oxidation or buildup on the internal passage. Should I just clean it thoroughly with solvent and a test tube brush or similar?

[Walt Fricke]

Sounds like a plan. Maybe some kind of round brass bristle brush? Rifle bore metal brush? Nothing to hurt in there, no bearing surfaces to mar. All that stuff you got out would scare the willies out of most of us, though it seems it isn't common. Makes sense to work until nothing but clear solvent comes out just to be sure.

[KTL]

My last build I too was shocked how much dark stuff kept washing out of the shaft interior.

Yep I would just clean it out with a tube brush. McMaster has a wide selection of them to get you just the right size so you're not diddling around with a brush too small (hard to be effective wiggling it around) or too big (gotta ram it in there and hard to twist it for effective cleaning)

[mikedsilva]

maybe an ultrasonic parts cleaner...