I have a Yanmar 2QM20 head
(on the bench) and the injectors are well and truly seized / stuck in the head
and I am looking for ideas or advice on how to remove them
So far I have tried various penetrating fluids and rust releasing agents (Mouse Milk, H-72 Reducteur, ATF/Acetone mix, diesel
and others). Each have been left soaking for several days.
I have tried rotating the injector body using a breaker bar with about 4' of extension pipe - no movement.
I have tried a slide hammer (attached to the 8mm thread at the top of the injector) after each soaking but even with repeated blows dozens and dozens of times - no movement.
I need much more force or serious heat or to remove the rust which presumably is holding the injector in place. Quite possibly the injectors have never been removed in 40 years of service
I haven't tried an air impact driver but feel it could likely damage the injector flats and I can't see anyway of using more force than the slide hammer.
I reluctant to use serious heat as it might damage the head or injector nozzle and housing.
Currently considering making up an electrolysis
bath to see it that will remove the rust but I have never tried this and I wonder if it will cause other damage to the head.
Also thinking of refitting the head to the engine
, leaving the injector clamps slightly
loose, spinning the engine
over with the starter motor
while squirting some diesel
into the inlet manifold which the hope that it will fire a couple of time and blow the injector out.
As this engine uses a pre-combustion chamber, I can't see anyway of forcing the injector out from the other side.
Perhaps I can make something to replace the top nut but I can't really see any way to exert more force to pull the injector out.
Any ideas (or cautions) are very welcome at this stage
but please don't suggest soaking it with penetrating fluid - that hasn't worked so far