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I have a valve slide holder in my 6th cylinder (please see pic) that is broken at the top of the stem.

Is there a reasonable way to repair this?

Thanks for your input.

Gar

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Pulling out the valve guide and pressing in a new one is the only fix. That's the kind of thing that I prefer to have a shop with the proper tools handle for me.

The new valve guide will need to be reamed to fit the valve stem after it is installed in block. Valve guides should be available.

Yeah just take the block to a shop and have them replace the guide. Usually no big deal.

FYI: Agree with having a familiar engine mechanic either do it at your place or take it to them...there are some simple knowledge/tricks/tools that they typically have that will get it done quickly/correctly.

Remember, there are usually circlips/keepers on the inner edge of the guide where they penetrate the casting so you need to access them through the valve cover...and pad it with cloth/paper towel so when they go "sproing" they dont get lost in the abyss...a tailored reverse pliers is needed to grab circlips and expand them properly.

Also, once the keeper is removed, the guide (as noted by others) is a LIGHT press or line to line fit into the block casting. There are valve guide removal tools that slip through the guide hole and are retained on the inner side as the feet of the tool rest on/around the outside/upper/visible zone of the guide...there is typically a threaded nut that slowly pulls the guide out towards you...much like a wheel puller does...DO NOT HAMMER ON ANY OF THIS HARDWARE.

Then, the new guide is lightly pressed into the casting hole with a (need experience to not bugger this part up) slow light symmetric press-in or brass hammer on a softer metal drift pin that contacts the guide aperture.

Once it is in, the circlip/keeper (often need a new one) is replaced and then mic the valve stem and guide holes. There are specific diameter/tolerance ranges in the service manuals...read them and follow them with your light reaming, because the gap is CRUCIAL to get the valve to fit in the guide and onto its tapered seat while leaving enough room for differential thermal expansion of the guide and valve as the engine heats up WITHOUT BINDING OR SEIZING.

You may also need to adjust/grind the valve stem length so that it achieves the proper clearance gap relative to its lifter...you need a valve grinding rig to do this properly.

You will want to lightly lap/grind the tapered seat in the block to match the valve to the seat for good compression sealing.

Generally, if you are a reasonable mechanic, hire one once and join them as their helper to see the whole process/tools...you will then learn all the tricks/nuances and can replicate it thereafter.

I suggest that you/mechanic look at ALL the valves/guides/seats...since you have the head off and are in for a penny...its only a little more effort to do a full valve job/guides on a straight 6 and the benefits are noticeable, depending on how sloppy theyve become.