Guys,

injectors will go on this week, Plain and simply said, i need to know what advice, tips, and or procedures yall have to offer me. Thank you in advance..


Rick

 

After you take all the hold down nut, injector lines and return tubes off, find a piece of metal or PVC tubing or pipe that will fit around the injector. Cut it to length so that it goes from the head to about 1/2 way down the threads at the top of the injector. Put a washer over the top of it and use one of your lug nuts (clean it out first) to pull the injectors.

When you put the 370's back in, put some Nevr-Seez on em and IIRC use the thin washer (.020). Make sure the old copper washer came out before you put the new ones in.

If nobody else chimes in, I'll look up the torque specs for the hold down nuts, return banjos and injector lines.

Oh yeah, when you go to fire it up, pump the primer on the lift pump until you hear it push past the overflow valve, fire it up and "crack" each line at the injector to bleed the air off.

 

Wash the engine down before working on anything. Must be clean.

I didn't use any pipe. Just a GM lugnut, rolling head prybar for the front 3 or 4, and a regular prybar for the rest. Would suggest spraying down around the hold down nut with some PB Blaster a day or two in advance.

The fuel injection lines come off in one group. Leave them together.

IRCC, you need a 19mm wrench for the high pressure lines

10mm for the return line banjos and the bolts that hold down the air intake horn and the hold down on the return line next to the fuel filter plus the grid heater connector

12mm for the banjo bolt for the return line on the filter head

8mm for the high pressure line clamps that are on the intake manifold

35-44 ft/lbs for the hold down nuts

snug (but not to tight) on the return line banjos on the injectors. 10 ft/lbs maybe. Be careful.

18 ft/lbs on the intake bolts, plus put RTV silicone on the bolt threads

The grid heater gasket is reuseable, so don't tear it.

Make sure to start all of the fittings before tightening up any of them.

 

When I put my injectors in, I noticed that there was rust and paint flakes that had dropped down in where the injectors sit.
SO what I did was take the rubber bulb off of a kitchen baster and fitted the other half onto the end of a vacuum, then was able to get way down into the holes with a lot of suction power, it really worked slick. Sucked every right out, nice and quick.
Something to consider, Tim.

 

I used a shotgun bore brush and the swab and handle from a cleaning kit to clean the injector holes out then used a shop vac with a piece of copper pipe (easier to bend) fixed to it to clean them out. They have got tobe clean or they won't seal.

 

Magic question here

These injectors just slide in in place of the other ones? I can perfectly see how using a piece of tube over the injectors can a lug nut can get them out, i can also see how twisting them can make them come out as well..

But when you all say the hold down nut, im not sure im reading or understanding which one that is... BUT i do see that there will be a need for some WD 40 spraying on before hand to help loosen these things..

My whole debate is to do it myself, or have a local shop do it... Im not sure what to muster out of it...

Any more ideas? im open to suggestions....

Rick

 

The nut at the base of the injector while its in the head is hold down nut it takes a 24mm to remove it. It will come off the injector completly then you slip the pvc piece on then the lug nut and tighten. The lug nut will pull up on the injector while the pvc pushes against the head. There are rubber orings that seat in the top of the hold down nuts and have tobe replaced and of coarse your crush washers, Some people replace the ones on the return manifold but I never do.

 

1) Remove the air intake horn.
2) Loosen the fuel lines from the injection pump and the hold downs that hold them to the head.
3) Loosen the fuel lines from the injector ane remove the lines
4) Loosen and remove the fuel return lines from the side of the injector
5) Remove the injector hold down nuts
6) If you don't have any kind of injector remover, re-attach the fuel lines loosely to the injector and using a large pry bar gently pop each injector out of the bore (you only have to pop it a little bit to release the lock ball)
7) Check the bore in the head for dirt, carbon, old washers, etc...
8) Clean the bore as needed. Note: the bottom of the bore is what needs to be clean for the washers to seal. Use a shop vac and a small hose to clean the bore as needed. It only needs to be clean not polished
9) For 370s use the thinnest washer (.020 approx). Don't worry about the washers not sticking as if they fall into the bore, the injector will align it as long as it's flat.
10) Never-seeze the hold down nuts and re-install.
11) Replace the copper horse shoe washers on the return line and tighten
12) Replace the fuel lines and air horn.
13) Bleed the system as required and check for leaks
14) Enjoy...

 

a buger of grease on back of the washer will hold it to the injector so it don't fall off, very helpful on 5 and 6.