Other use for my PCNC 1100

My utility vehicle developed an out-of-warranty latent defect whereas the exhaust valve guide shifted up such that the rocker started pounding on it. After taking it apart & comparing the guide OD to the head ID there was maybe 2 tenths interference fit – not really enough. The new guides were clearly bigger by 8 tenths giving an improved interference fit of 0.001” - much better. However the new guides are made from Powdered Metal & they require their ID to be reamed-out to match the valves.

Since this gets messy and may require the seats to be re-machined I decided to reuse the old guides & glue them in with Loctite 640 – supposedly designed for this purpose. One of the requirements for doing this is a fast press – much faster than my hydraulic one.

So I made up a positioning plate & drift to use my 1100 to ram them in at 90 IPM. After finding my locations I heated the head up, applied Loctite to the guides per the instruction and ram them home.

As many of you may know, press fits can easily get cocked and not go well. Trying to do it fast is even more difficult. I setup my drift in a 1/2” R8 collet and tighten it so that if the worse happened it would slip up into the collet giving me time to hit the brakes.

Thing went well so time will tell if the glue job holds.

http://www.cnczone.com/forums/attach...d=375396&stc=1
http://www.cnczone.com/forums/attach...d=375398&stc=1
http://www.cnczone.com/forums/attach...d=375400&stc=1