Injectors

[Waterloo]

Doing the same here, bought the wrench off of Amazon, and the filters. Takes a few minutes to change out.

[AussieISX]

Had o go at repairing a leaking injector I had in number six cylinder today . I've had a fuel knock in six for a short time which I believed was a remnant from air cavitation. Last two years I've replaced all six injectors so all are fairly new . Number 4 caused a lot of problems until I realised I had air in the fuel. Did a leak test across both metering accuators to find number six making air . Stripped the injector and found a lot of carbon build up at the tip of the plunger and the tapered seat area where it clearly wasn't seating and sealing combustion gas . I used some carb cleaner and a tiny wad of polishing grade steel wool down the tip of the injector to remove all the carbon. The plunger was easy enough to clean and polish up . I then used aluminium polish and pushed the plunger back into the tip , spinning the plunger in the tip with alloy polish in there to lap the taper . After a very thorough clean of all parts I put it back together. So far so good. With the injector reinstalled the knock has gone and so have the bubbles in a follow up leak test . I believe the cavitation allowed the plunger to bounce off the seat in the tip providing opportunity for carbon to pass . Once anything contaminated the tapered seat it was all down hill . Hopefully it continues to seat and another injector won't be necessary

[Rawze]

(01-05-2017 )AussieISX Wrote:  Had o go at repairing a leaking injector I had in number six cylinder today . I've had a fuel knock in six for a short time which I believed was a remnant from air cavitation. Last two years I've replaced all six injectors so all are fairly new . Number 4 caused a lot of problems until I realised I had air in the fuel. Did a leak test across both metering accuators to find number six making air . Stripped the injector and found a lot of carbon build up at the tip of the plunger and the tapered seat area where it clearly wasn't seating and sealing combustion gas . I used some carb cleaner and a tiny wad of polishing grade steel wool down the tip of the injector to remove all the carbon. The plunger was easy enough to clean and polish up . I then used aluminium polish and pushed the plunger back into the tip , spinning the plunger in the tip with alloy polish in there to lap the taper . After a very thorough clean of all parts I put it back together. So far so good. With the injector reinstalled the knock has gone and so have the bubbles in a follow up leak test . I believe the cavitation allowed the plunger to bounce off the seat in the tip providing opportunity for carbon to pass . Once anything contaminated the tapered seat it was all down hill . Hopefully it continues to seat and another injector won't be necessary

I find this very interesting. Sounds like some alternative thing to do on older injector that maybe only has this issue and no other problems. Some pics would have been nice. - Maybe something that would eventually be good to make a video of? -- Who knows.

[AussieISX]

It seems to me if an injector is leaking, it has to be leaking past this tapered seat . There is basically nothing else internally sealing the injector from the cylinder. The one pictured is a good running injector with no soot build up from carbon passing the the lower plunger seat . I unfortunately didn't get any pics of the leaking one during the process. If the plunger and seat in the tip have no damage and just have carbon built up I see no reason why some older injectors can't be cleaned and re fitted .

[Brock]

This is the same thing a local injector ship said to me, if you fail the bubble test it doesn't mean the injector is bad all the time, a lot of the time they just need to be opened up and cleaned of the carbon that's causing the plunger to not seal.

[hhow55]

Maybe, someone would do a video on how to do this procedure.

[Nilao]

I have a local rebuild shop in my area. I wonder if they could rebuild mine. They offer a one year unlimited mileage warranty on all their work.

[Brock]

(01-07-2017 )Nilao Wrote:  I have a local rebuild shop in my area. I wonder if they could rebuild mine. They offer a one year unlimited mileage warranty on all their work.

I don't know about the isx injectors but on my sdp cat, injector shop rebuild's suck! For that matter, what I hear is the cat remans are pretty much the only way to go.

I bought 6 rebuilt ones from a local shop with good warranty. Problem was when we put it on the dyno and measured flow rate, there was a 25% difference between the injectors. Now I did not have the trim files installed but I'm pretty sure that doesn't account for that bad of a spread!

The money I saved is not worth it. I'm rebuilding the motor right now and oem injectors are going in.

[Rawze]

Taking one apart to clean some carbon out of it and trying to save it yourself is one thing. Paying someone a few bucks to do the same is another,.. But taking them to a re-man shop and paying 50% or more of the price of a new one in my book is NOT worth it.

Here are my thoughts on re-man injectors, and injector re-man shops in general...

http://rawze.com/forums/showthread.php?t...67#pid4367