Injector needles stuck

Not sure exactly how or why but I have a set of Schied injector nozzles that have the needles seized in place. They are 5x.018 and have been out of the truck sitting in my air conditioned garage for a year. Was getting ready to put them in a new motor and took them apart to clean them. Soaked them in PB blaster and still wouldn’t move. Finally heated the nozzle and it finally popped free. The needle looked fine with no marring of any kind and the inside doesn’t look bad either. Cleaned and put it back in and it’s too tight to go back in without force.

Has anybody delt with this before? Am I missing something here? I don’t want to use Emory cloth unless thats the right answer. I’m just kind of baffled why they would all be like that.

I bet an ultrasonic cleaner would clean out the nozzles, harbor freight sells a cheap one, good to have around anyway. Found out by accident Simple Green degreaser works awesome in the sonic cleaner.

An ultrasonic cleaner isn't going to help, depending on what the issue is they may need to be lapped in the guide area.

I’m assuming fine valve grinding compound would work effectively? I put the needle on a flat machinist stone and saw an area 2/3 down that looked to be slightly raised compared to the rest of the collar.

Is this something you run into regularly Smokem?

gmanss said:

Is this something you run into regularly Smokem?

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It isn't uncommon on the Ambac nozzles, I use 2.5 micron diamond lapping compound, it requires very little as it is easy to overdo and create too much back leakage.