The piston is not visible until you remove the prechamber. To remove the prechamber, you need a splined socket to remove the prechamber collar and a slide hammer with an attachment. The valve cover has to come of for this and the tools are about $200.00. After the prechamber is out, you can see the piston.

EDIT: After posting this, I just realized that to get the prechamber, the glow plug has to be out as it protrudes into the prechamber. Forget the above idea.

JC

I would think disabling the pump and cranking it with the glow plugs out ala 617 glow plug replacement rpocess would work to blow any residual out.

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Sharing my partner's 2012 Forte 5dr SX til I find my next 123 or 126..
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Do I miss being a service advisor ???

Since the glow plug does actually protrude into the prechamber, why would you need to see the top of the piston? Just fill the prechamber with the fluid.

I thought there was a direct route from the injector hole to the piston through which I could snake the vacuum tube to remove most of the fluid. No? If not, then turning over the engine with either glow plug out or injector out would remove the fluid without risk of hydrolock. Would be a mess.

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2009 E320 Bluetec 117,000
1995 E300D 306,000 Sold
1996 Ford Taurus LX 130,000 Sold
1985 300TD Still 225,000 Sold
2016 Ford Fusion 24,900

That's where an old beach or bath towel would come into play..

__________________
Sharing my partner's 2012 Forte 5dr SX til I find my next 123 or 126..
-
Do I miss being a service advisor ???