Thinking out loud here; since the hole there is a through hole, would it not be possible to use a fine and soft pipe cleaner on the housing, followed by a thorough rinsing with solvent?

Given that this is such a critical component, it would seem that replacing the entire assembly would be the best option. However, as Mark states, there are instances when "extreme measures" might need to be undertaken. (Or, perhaps, you need a hundred miles or so of service from the injector to get to where you could buy new ones.)

-blaine

 

I was reading on the HD forum and someone was asking about Seafoam.
That got me to thinking maybe it would work as a solvent in this case.
After you soak then stick it in the ultrasonic cleaner it would take the varnish
off and not damage it.

Maybe a new use for Snake Oil.

Sean

 

I think what we don't know about the spool valves is what surface finish and surface treatment is put on new valves so we don't know how to recreate that, and I do know that there can be some very sophisticated surface treatments on parts like that these days. The other thing we don't know is what happens to the surface after stiction has become a problem so we don't know if simply cleaning varnish is the actual solution. I suspect that if it was, a solvent solution would be here and we'd all know about it. I suspect that some surface wear, galling, corrosion et al is at play to create the stiction in the first place, and all the cleaning in the world might not fix that.

My personal approach is to run the latest flash that uses inductive heating to get the oil up to a usable temperature faster and prevent stiction, and to realize that injectors are, at the end of the day, wear items that need to be replaced every once in a while, and to run the best oil I can in them.

Brian

 

600 grit seems really coarse and won't leave a very polished finish. A coarse finish woudl be more likely to get build-up on it again. I would be more inclined to find a solvent to remove the varnish. Also, I thought Ford had a DLC (diamond like coating) on the spool valves after 2003, so wouldn't this just be removing that?

 

Your not gonna remove any material from the spool valve with 600grit paper by hand. The DLC is hard chit! 600grit paper will only remove the varnish build up.



Another member on the Org posted this same video, then by luck, Dale got permission from his boss to give it a try with a truck that was going to auction.

SPOOL VALVE STICTION POLISHING - Ford Powerstroke Diesel Forum

 

Just a thought since I'm feeling empowered(read: dangerous ) Could the 600 grit be leaving a hone on the spool that acts like a newly honed cylinder bore, therefore refitting itself to the injector housing bore? Or causing it to remove the varnish from the bore, in effect reseating it?
I'm pretty cheap so I may try it if the need arises.

At any rate I'm a long time outboard motor fiend so I'm not a plebe when it comes to decarbonizing or cleaning varnish from combustion surfaces. Granted I am are dealing with far greater tolerances than an injectors, but there are some carbon cleaning sprays the do a fantastic job of dissolving varnish without eating metal. Yamaha makes a spray that kicks @ss in that department. A soft bottle brush would provide all the agitation necesarry as long as you blunt the twisted metal holder to prevent gouging.

 

I never got a chance to measure the OD of the spool valve or ID of the coil body. You can imagine the tolerances involved by looking at the fuel plunger to injector body, and oil piston to injector body.


Fuel plunger OD was .24977" and body was .2499, the oil piston was .66905" and body .66915".

 

Thanks for posting Rich.

 

I would be very interested indeed in knowing what those clearances (basically a tenth of a thou) change to when the parts are frozen to 0 degrees F. Normally the ID of the bore closes up more than the OD of the piston, so I would expect the clearance to get even smaller.

I'm also curious how much that lab grade inspection equipment cost - more or less than my truck!

 

 

It a little more than a few hundred bucks aint it brother? Lol.
I've only changed out injectors on spark plug engines. When first seeing the video and reading the first posts i couldnt help to think what do you have to lose. The concerns you have expressed has since gotten me thinking.
The thing about this engine is someone comes up with a fix or mod that shows great results right now but turns out to do more damage than before. Its left me gun shy.
So all this being said what if one was to remove/clean the valve as a maintance item? Or perhaps at the beginning stage of stiction? Is there a way to tell its starting? How big of a job is it to remove the injectors to check em?
This seems like a sound solution to the problem but then again so does alot of the other mods.
Im wondering if the video is just showing the steps and not the actual work. If those few twist of 600 grit removed the varnish 1000 grit will remove it in with just of few more. Did anybody else catch they had a new injector but didnt take it apart to show difference in varnished valve and good valve? I thought that was odd. Why mention it at all?

 

The main thing I noticed was it was done to a truck that was headed to auction. I liked Sean's idea best about using a solvent in an ultrasonic cleaner, where you could disassemble the spool valve and put both the valve body and spool valve in and clean them both. But this got me thinking about reassembly with respect to making sure you have the bolt that holds everything together tight enough so that it will not come apart with engine vibration and also making sure you don't over tighten it. For me there are just to many variables to chance this on such a critical part. But I guess if you were hard up enough and strapped for cash this could be a viable alternative to running with sticking injectors vs doing nothing.

 

@mustang_309 yea I caught that one too. Wonder if its still going to auction. Going to make buying these trucks alittle dicer.

 

The nut if I recall right looked like a self retaining type.
To the only thing is getting it to the right toque to
compress the coils.

Sean

 

Is there a tech note or description of how to take the injectors apart, with torque specs and such?