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[kpasko]

I have a 1978 924NA, and I was attempting to replace the plastic/phenolic injector housings when I was replacing the o-rings. The first one came out without a hitch, but the second one turned out to be a huge ordeal, to the point of not being able to firmly house the injector...long story short, engineer friend wisely attempted to slit the plastic along one side and pry it out from the threads...turns out someone before me decided the housings were leaking air and gasket-sealed them in, so now I have to get the thing out. I've thrown in the towel on the other two and just swapped the o-rings and left the housings alone, but I'm still left with how to get the tattered remains of the crappy housing out in a reasonable way, and clean up all the little bits that have fallen down on top of the valves.

Other than the more wild options of taking the head off and having a shop take care of it (and doing a port and polish while they're at it), or throwing up the hands and doing ye olde audi 5000 or vw tdi swap, any recommendations as to how to safely remove the remainder of that annoying housing? Similarly, are there any recommendations as to how to remove the other non-destroyed housings safely; I have a 12mm allen which seems like the right size but slips on the corners (hooray plastic), but maybe an incredibly tight 13 won't slip?

Thanks for any help!

[kpasko]

-bump-

no help on this one guys?

[emoore924]

IIRC, the head of a 17mm (14mm?) bolt will fit tightly into the opening and allow you to unscrew the plastic plug. Just double-nut it and use it to remove the plug.

Not sure about the goo used by the PO to seal the plug. You might have to heat a razor blade red hot, cut the plug into 1/3's and remove it piece by piece. Don't forget you want to preserve the threads so you can screw the new one in. So don't bugger them up prying the old plug out.

You do NOT want to start the motor with anything more than the tiniest of crumbs in the valve chamber. Bits might get sucked through ok, but they might not, the plastic is pretty hard, and anything more than a morsel might bend your valves, which would be bad. Probably the best solution would be to take the intake manifold off and carefully clean/remove any bits that have fallen into the head. Hopefully all the intakes are closed so nothing fell into the combustion chamber (you can tell from the positioning of the cam lobes where the valves are in their cycle.)

[kpasko]

thanks for the reply emoore.

I'll try out double-nutting; the 12mm allen I was using fit pretty darn snugly, so I'm not sure if any variety of torquing out will help, but worth a shot. Maybe heating something slightly oversized and melting it in, then double-nut?

Somewhat resigned that I might have to carve it out piece by piece, but I am worried about the threads, as you mention. I do have a machine shop at my disposal so could hypothetically re-tap the hole, cutting the extra crap out in the process, but not sure what the exact tap size/pitch is on it (any of you internet wizards happen to know?), and would hate to doom the car to custom housings for all eternity if I can't find the exact fit.

Definitely not starting the car until its all fixed up; from looking at it I think I got lucky and the valves are all closed, so it will just be a matter of meticulous cleaning; or of course taking the whole head off to make sure there's nothing on the pistons...and shipping it down to European Motorworks while I'm at it

Thanks again for the suggestions!