Fuel inectors

09-17-2020, 08:58 PM
Look at the of fuel injector there is a little pipe at the bottom, does it spray fuel too and which why should it be installed in the frame? And this is one of the old injectors i remove from the TBI.

https://i.postimg.cc/rD8yYwSB/IMG-95.jpg (https://postimg.cc/rD8yYwSB)

https://i.postimg.cc/WdbjwfVj/IMG-96.jpg (https://postimg.cc/WdbjwfVj)

Blue Bowtie
09-19-2020, 06:44 PM
Two things;

1. That is probably acutally the roll pin used to locate/position the injector in the pod, so pay attention to orientation when assembling. Fuel is actually admitted to the injector via the nylon screen surrounding the lower extension.


2. It appears the injector pod casting has been bead blasted. That's going to make it pretty difficult for the O-rings to seal the injectors to the casting, and may result in fuel leakage. There is a specification for surface finish for a typical static O-ring, and I would bet that a blasted surface is nowhere near the spec of 16 ra (microinches) RMS, or 0.4 microns. In fact a smoothly machined surface produced by a larger radius tool tip often only barely achieves that. A 150 grit glass blasted surface is frequently aound 50 ra.

https://www.parker.com/literature/Section IV.pdf

Do you have any surface finish gauges? if not, this is one of the cheapest you might find:


Polishing with a 240 grit abrasive can produce (barely) a 16 ra. Polishing with 320 grit abrasive can produce 8-10 ra, which would be acceptable. You may have some work to do, but it's not going to be easy down in the lower O-ring seat.


09-24-2020, 09:31 PM
https://i.postimg.cc/rdJjwmSW/IMG-200.jpg (https://postimg.cc/rdJjwmSW)

Thanks but i had found out which way the injectors are suppose to be installed but changing both fuel injectors didn't solve my stalling problem and this TBI does not use the steel O-ring all it use is the small rubber O-ring that sits at the bottom next to the screen filter and a big rubber O-ring on top.

With the new fuel injectors the car is stalling quicker now, start it up and it stalls foot on the gas it doesn't stall, foot of the gas it stalls and it doesn't stall when i uninstall the air cleaner.

Is there a way i can reset the Idle Control Valve and where can i find the fuel and air mixture screw?

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