Doing a taller grout fill on an already filled block?

[KnightEngines]

Got a block in, it's been filled by the owner, but the fill is very short, a solid 1.5" short of where I usually fill them.
Has not been run, filler is regular moroso block filler.

Can I just fill over the top of the existing fill or am I gonna have issues? - I can leave it, it's not critical, but I'd like to fill it higher if it's not a problem.

[user-17438]

An epoxy style may be a better idea. But I guess of you acid etch the old grout it should bond.

[statsystems]

I've done it several times. I've never etched the original filler but that doesn't sound like a bad idea.

I knew what they original filler was each time (happened to be Hard Block) and I just filled over the top of the original stuff.

[Frankshaft]

It works. I have done it. Think about it, even if it just sat on the top of the old fill, where is it going once its solid. It doesn't really "bond" to the bottom of the block. If you cut the bock apart, and had access to the filler sitting on the bottom of the block, I bet it would take very little effort to get it to release from the cast iron. Before I did do the above, I made up a little, poured it into a cup or whatever. Let it set. Put antifreeze on the top for a day. Poured off antifreeze, rinsed the top off like it would be in a jet wash. Then Make up some more, poured it over the previous filler, let it set, peeled the cup away, and it was fused. It wasn't coming apart.

[KnightEngines]

Nice!

Thanks guys, I'll fill it higher.