Forum Discussion
Kayteg1
Jan 03, 2016Explorer II
Technology changes all the time, but as of today you have older technology diesels with injector pumps and newer cdi technology with high-pressure pump, common fuel rail and electronic injectors.
Powerstrokes use oil pressure to compress fuel in each individual injector, but with electronic injectors the principals are close to cdi.
Only very old injector pumps had priming pump that could be hand-operated to bleed the air from low-pressure lines and filter.
For bleeding air from high-pressure line you would crack nut on steel tubing at the injector.
On rail injection system usually you have electric priming pump and bleeder on filter.
You open the bleeder and turn ignition on without activating the starter, what turns electric pump for few seconds.
Once you see fuel coming from bleeding port, you close it and let the high pressure pump to push reminding air via injectors.
Lot of injectors don't like air in them so beware of running diesel dry as some Ford mechanics say it can cost you $4000 in piezoelectronic injectors replacement.
Powerstrokes use oil pressure to compress fuel in each individual injector, but with electronic injectors the principals are close to cdi.
Only very old injector pumps had priming pump that could be hand-operated to bleed the air from low-pressure lines and filter.
For bleeding air from high-pressure line you would crack nut on steel tubing at the injector.
On rail injection system usually you have electric priming pump and bleeder on filter.
You open the bleeder and turn ignition on without activating the starter, what turns electric pump for few seconds.
Once you see fuel coming from bleeding port, you close it and let the high pressure pump to push reminding air via injectors.
Lot of injectors don't like air in them so beware of running diesel dry as some Ford mechanics say it can cost you $4000 in piezoelectronic injectors replacement.
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