injector bushing replacement

[auditude at cox.net]

My observations on the spot welds you saw are that there are two stamped/formed sheet metal sections to the tips.  The inner section forms the upper lip that holds the bottom seal, and the outer section forms the lower lip that holds the same seal.  I believe the spot weld holds those two sheet metal pieces that the tip consists of together, but they can be removed as an assembly from the injector itself.  The two ridges create a channel that the lower seal sits in.

If it weren't spot welded, you could imagine that the assembly process onto the injector was:  inner tip piece, then lower seal, then outer tip piece.  The outer tip piece is shorter than the inner, and doesn't "butt up" against the inner pieces ridge.  The inner tip piece folds over the edge of the injector.

I would agree that you would want to keep these tips as tight as possible and not loosen them by removing them from the injector (alot or at all).  I just think the little spot welds hold the tips together, not onto the injectors.

Ken

Steve Sears Steve Sears" <steve.sears at SHOESsoil-mat.on.ca wrote:

Nate,
Did the replacement about a year ago - pulled one injector and it was
missing the tip cap - turned out it must have fallen off and been eaten by
the engine (yikes) - Phil Payne suggested that the turbo could have ingested
it no problem, but I suspect that the helicoiled #5 spark plug hole might
have been associated with the loss - also the previously reused stretched
head bolts the shop took out when replacing the head gasket last May.  Hmmm.
Someone suggested pulling the tip caps off with pliers, but I'd avoid that
and try to stretch the seals over the tip somehow - it appears that the tip
caps on the injectors I removed (the front 4, anyway) the caps had tiny
spot-welds on them to hold them on.
I used channel lock pliers and a screwdriver (lever) to pull the injectors -
be careful of the fuel lines (and the pressure contained within!!!)