M42 Block Reconditioning

[KenC]

My #4 cylinder died (fouled plug, stuck open injector or a combo of the both), so I decided to just re-ring all of them and recondition the block a bit.

I'm planning on buying a flex-hone (dingle-ball hone), and de-glazing the cylinder walls.  I think the cross-hatching still looks pretty good, so it shouldn't need a machine shop hone.  What do you guys think?


#4 is the closest one to the camera.  The little jagged line near the top of the bore isn't palpable at all... I'm not sure what it is.





Again you can't feel that little line at all, so I'm thinking the flex hone will clean it all right up.

[nicknikolovski]

What will you be replacing as far as parts for this project?

[KenC]

In the block, I'm just replacing the rings and the thrust bearing (updating to the 360 one).  All of the rod bearings and crank bearings appear to be in immaculate condition (I can still read the part numbers on all of them).  I had a hell of a time even getting the crank to come loose from the bearings, the fit was VERY snug.  The block has about 120k on it, and spend 90% of it's life in an auto e36.

[DesktopDave]

They look great to me, but I'm no expert.  I've heard discussion of using a ridge reamer to cut the top even & leave the rest alone.  I've also been told that the ball hones were hard to use?  Not sure.

Amazing that it's so clean.

[txleadfoot]

Looks good.  How many miles?

[KenC]

Looks good.  How many miles?

The block has about 120k on it, and spend 90% of it's life in an auto e36.

[doitover]

You have it all apart, it may not be that expensive to have a machine shop clean it up for you.

[dvmotorsports]

You've got some serious scoring in there. All those vertical lines are clearly visible in the last three pics. You can try the flex hone, but given the scoring you have, and you have it apart, i agree with the above statement. Run it by the machine shop.