Intermittent ticking then clacking of an injector (solved)

[ORCoaster]

What causes fuel injectors to tick?  Mine was doing that after I checked the compression yesterday.  Then as I was running around town and the heat of the engine went up to where the fan kicked on one injector, # 1 I think, really started clacking and I was blowing blue smoke out the back.  I have since brought it home, got it to clacking by raising the RPMs.  Once I get it there if I release the nut on top the injectors the clack goes away and the idle gets kind of rough.  Blue smoke rolls at that point.

I pulled the injector and double checked the heatshield fitment and put it back together.  Got it to quiet down but it may get it back if the temperature goes up again.

Any ideas what causes injector clack?  Is it timing?  If so why wouldn't the other three be doing it?

[burn_your_money]

Injectors don't always wear evenly so that one may have a different opening pressure than the others.

Since it happened after you were messing with the injectors a piece of junk may be causing the needle to stick under certain conditions. A good hard drive may clear it out, but it may also explode your motor if something is really wrong (unlikely though).

[ORCoaster]

Well, later this week I need to head south for 225 miles and I was hoping not to blow something up on the way. 

So something is inside the injector?  Could I just take it apart and blow it all off with air?  or is it down in the bottom of the injector?  I have seen the exploded diagrams of these injectors.  Doesn't look complex at all. 

Why would the engine smoke visibly when clacking like it was if less fuel is going into the cylinder than required?  Just not firing any of it if the right amount isn't in place? 

And the compression test was perfect too.  Well always something on these bunnies isn't it.   

[8v-of-fury]

Why would the engine smoke visibly when clacking like it was if less fuel is going into the cylinder than required?  Just not firing any of it if the right amount isn't in place? 

It is smoking because something is inhibiting the injector from atomizing the fuel correctly, and that cylinder is not performing 100% combustion.

[ORCoaster]

OK, makes sense.  If it is not opening correctly and pissing a stream in there I can understand why it isn't burning right and clacking like that.  I might have to up the ATF in the fuel mix in the future to clean these out better.  I just put them on 6 mths ago and they looked pretty dirty.  Maybe some other reason for that.  I did have it retarded to about 78 mm until just recently when I got the dial gauge.

[8v-of-fury]

It would not hurt to run it straight on ATF, it has been known to help a lot.

ATF has some incredible cleansers and detergents in it.

[ORCoaster]

That is why I run it in the fuel then at the end of an oil change.  I think you do the same. 

So why doesn't it come out of our coveralls? 

[burn_your_money]

Why would the engine smoke visibly when clacking like it was if less fuel is going into the cylinder than required?  Just not firing any of it if the right amount isn't in place? 

It is smoking because something is inhibiting the injector from atomizing the fuel correctly, and that cylinder is not performing 100% combustion.

Another possibility is a piece of dirt is holding the needle open and fuel is being injected during all 4 cycles of that cylinder.

[8v-of-fury]

That is why I run it in the fuel then at the end of an oil change.  I think you do the same. 

So why doesn't it come out of our coveralls? 

I run ATF whenever I think it needs a good cleaning, not all the time though. I generally run either the grey or white Power Service depending on season.

IT stays in the cotton fibers of our coveralls to provide a long lasting forever clean! lol

[ORCoaster]

Say there was a piece of dirt or more likely return hose that dropped down in there, could I put a vacuum on it and suck it out? 

At idle there is no clack, Rev high and it started, cracked the nut on top to relieve pressure and it stops.  Goes back to doing it when I revvved it up again.

Is there any calibration that will be ruined by taking it apart?  I didn't think so but want to check that as I don't have a pop tester.  Does the needle come out or is that another sealed unit of some sort?

Found replacements for 15 each but won't have time to get before I need to drive.  Might look local, Diesel Injectors (?) just up the road.

[oldpoopie]

I'd try a can of dieselpurge first

[R.O.R-2.0]

I'd try a can of dieselpurge first

good call!

[ORCoaster]

Purge it is, Besides that is something I can do in the dark on the street in front of the house with a flashlight.  All before I go for the long drive.  Thanks

[rallydiesel]

You won't be able to suck anything out of the injector. I would pull it and take it apart, clean and blow everything out with compressed air and reinstall. You won't screw anything up (worse) this way as far as calibration unless you don't put it back together properly.

[ORCoaster]

Thanks, this too can be done in the street with a flashlight before the need to drive it long.