Valve Guide Replacement in IXB-3

[Jethrow]

Has anyone replaced valve guides in an IXB-3 motor?  Service manual says they should be driven down with a punch and broken off at the bottom to remove the piece remaining in the bore.  Seems a bit harsh.  I've seen videos where the guide is threaded with a tap and removed with an all thread and short piece of pipe.  Like a gear puller.  Also states that the valves should be replaces when worn but gives no dimension for a new valve stem.

My motor is blowing smoke and oily bits from the exhaust.  Compression is 110 110 100 110 and leak down test shows good valve seating.  I'm suspecting worn valve guides but I don't know if I should also replace the valves.

[Lowspeedlife]

Howdy Jethrow,
New intake valve dimensions for part #27140 are:
head diameter 1.490 inch.
Stem diameter.310 inch.
Length 3.950 inch.

New exhaust valve dimensions for part # 28212B are:
Head diameter 1.358 inch.
Stem diameter .310 inch.
Length 3.926 inch.

These are not my dimensions, I got these from a site on the net. He states that "the dimensions are as close as he could get" & "he does screw up" so keep that in mind.

I've never replaced the guides but from the description you give it sounds like the guide will bottom out before it completely exits the bore so you break it off then drive the rest out? It does sound harsh. I can't imagine that it would be damaging to try to thread & extract them the way you describe with all thread & a section of pipe, just try to protect the deck surface with a washer to keep the section of pipe from gouging it, if it slips or turns. At the worst, it doesn't work & you can drive them down & break them off.
Scott R

[Jethrow]

Lowspeed,

Thanks for that information.  Looks accurate because the Service Manual states that the new guides must be reamed to .0025 inch clearance using a 5/16" reamer.  5/16 = .3125 - .3100 = .0025 and that would give the correct tolerance.  Now I just need to measure my valve stems.

I've seen valve guide seals for .310 valve stems for various engines.  It would interesting if they could be worked in somehow to avoid pulling the head.

Jethrow