Seized Injectors - Need Ideas to Remove!

[US1Fountain]

I've heard many times of people melting wax from a candle onto a rusted/stuck nut/bolt.
Never tried it myself nor know why/how it could work, but when I was following that topic, almost everyone that commented said it worked for them.

[JPA Cate]

Well, Wottie, you're on your way now, good luck with it!

Ann

[Jim Cate]

Originally Posted by JPA Cate

Well, Wottie, you're on your way now, good luck with it!

Ann

and you are one persistent bugger, you are!

Jim

[model 10]

You ask what a machine shop would do? Take a welder and stick it in the injector. That will shrink it right up. That's how you remove valve seats too.

[kmacdonald]

How long was the engine submerged in saltwater?

[boden36]

To answer your question, the injector body is a tube , relatively thin. It is contained by the head casting, and possibly insulated from it a little by corrosion etc.
If you heat a longitudinal strip down the tube , preferably until it glows dull red, it will try to expand but will have nowhere to go. The heavy head casting will stay relatively cool and not expand much. The bit that you heated red will bunch up, and on cooling , the tube will shrink.

This is the same as putting a weld line down it, as suggested by Ecos. If you try the welder route, make sure you don't burn through and weld the tube to the head!


Regards,
Richard

[Olddan1943]

Start with the most conservative suggestion. You can always use a bigger hammer.

[Wotname]

Originally Posted by Ecos

You ask what a machine shop would do? Take a welder and stick it in the injector. That will shrink it right up. That's how you remove valve seats too.

Originally Posted by boden36

To answer your question, the injector body is a tube , relatively thin. It is contained by the head casting, and possibly insulated from it a little by corrosion etc.
If you heat a longitudinal strip down the tube , preferably until it glows dull red, it will try to expand but will have nowhere to go. The heavy head casting will stay relatively cool and not expand much. The bit that you heated red will bunch up, and on cooling , the tube will shrink.

This is the same as putting a weld line down it, as suggested by Ecos. If you try the welder route, make sure you don't burn through and weld the tube to the head!


Regards,
Richard

Thanks Gentlemen, I now understand the physics behind the process.

Should the head be hot or cold before using the heat in the injector - I'm guessing hot but also thinking cold?????

[Wotname]

Originally Posted by kmacdonald

How long was the engine submerged in saltwater?

I not aware that it has ever being submerged but it possible, it's 40 years old and I have owned it a couple of months; it's a project .

[boden36]

I would have the head at normal room temp.

[Ninedotsix]

Not a good situation, but my experience with this on 2QM15 engines in the past may apply.
I used the retaining studs and clamp plates to "press" the injectors out.
Be sure studs are ready to remove, and not themselves seized in the head.
With clamp plate off, run nuts to bottom of thread on each stud.
Set plate in place, and using a metric bolt that fits thread in the injector cap, and suitable stout washers, draw the bolt tight.
Create pressing tension by turning the stud nuts CCW, so that extracting force is applied.
With this tension created, heat the head around the injector, intensely.
I used oxy-acetylene flame
Be sure the tension on the studs is equal, based on torque force you apply to the nuts.
Try increasing tension as heating is continued.
If unsuccessful in first attempt, allow to cool to 140-150 F, then flood with penetrating oil, and allow to cool.
Lubricate the stud nuts with grease, heat and try again.
It was successful 3X for me on 2 engines. I keep the cap screw and washers in my kit, now.
When I had head professionally rebuilt, I described this procedure to the diesel head rebuilding shop foreman, and he liked it.
Plan to have the injectors rebuilt and tested (or replace), and supply new studs, nuts and insulators when reassembling.
My $0.02

[Wotname]

Originally Posted by Ninedotsix

Not a good situation, but my experience with this on 2QM15 engines in the past may apply.
I used the retaining studs and clamp plates to "press" the injectors out.
Be sure studs are ready to remove, and not themselves seized in the head.
With clamp plate off, run nuts to bottom of thread on each stud.
Set plate in place, and using a metric bolt that fits thread in the injector cap, and suitable stout washers, draw the bolt tight.
Create pressing tension by turning the stud nuts CCW, so that extracting force is applied.
With this tension created, heat the head around the injector, intensely.
I used oxy-acetylene flame
Be sure the tension on the studs is equal, based on torque force you apply to the nuts.
Try increasing tension as heating is continued.
If unsuccessful in first attempt, allow to cool to 140-150 F, then flood with penetrating oil, and allow to cool.
Lubricate the stud nuts with grease, heat and try again.
It was successful 3X for me on 2 engines. I keep the cap screw and washers in my kit, now.
When I had head professionally rebuilt, I described this procedure to the diesel head rebuilding shop foreman, and he liked it.
Plan to have the injectors rebuilt and tested (or replace), and supply new studs, nuts and insulators when reassembling.
My $0.02

Thanks Ninedotsix, your input is very much appreciated and again I note you are another first poster but long time CF member - it's becoming a movement!

You have explained the process well and I might try it soon. It would certainly work on "less stuck" injectors so I should try it on these "more stuck" ones.

[Wotname]

Update: The injectors are OUT!

Before and after pics

For the long story, see my next post!

[Jim Cate]

Originally Posted by Wotname

Update: The injectors are OUT!

Before and after pics

For the long story, see my next post!

HUZZAH, HOORAY AND HOT STUFF!!!!

Well done Wottie... we await the full story with bated breath.

Jim

[Wotname]

Here is the longer story of how I removed the seized injectors.

First up though, I want to thank everyone who posted advice and especially the long time members who made their first post in this thread - a special thank you to you.

I did consider all approaches you posted and while it could be said the application of lots of heat and force first up would have saved time, I choose to work up gradually in the application of both heat and force. In the end, it was apparent that one injector was way more stuck than the other.

So since Nov 28, I placed the head completely in a caustic soda bath for about 3 or 4 days to remove as much carbon / oil etc as possible. Removed from that and pressure cleaned and neutralised in a weak vinegar bath. I then made up a couple of mild steel anodes that would sit immediately above the injector bodies and placed the entire head in an electrolysis bath using sodium carbonate (washing soda) as the electrolyte. 3 or 4 days of bubbling away removed a lot of rust from around the injectors. This was then pressure cleaned and the slide hammer and lever was tried again to no avail.

So using MAPP gas, I heat cycled each injector a couple of times using both water and ATF/Acetone to quench. The MAPP gas was not hot enough to get any colour change. This time one of the injector bodies yielded to the lever and slide hammer combination. I thought I was on a winner!

But no, the other injector still wouldn't budge. Assuming it just needed a couple more heat cycles, I applied MAPP gas heat again and again and again (quenching each time) but no joy. Still thinking maybe only a bit more force was needed, I welded a shackle to the top of one injector and used an hydraulic ram to try to pull it out. I managed to pull the cast steel injector body in half (it was ~20 ton ram). Clearly more force wasn't the answer so that only left more heat...

Courtesy of a neighbour, the oxy / acetylene torch was applied and the stuck section was heated to red hot and quenched with water. Not wanting to waste the neighbours time, it was heat cycled to red hot twice again (with water) and twice more with ATF/Acetone and then the lever / slide hammer was tied again. Still no movement so after some more head scratching we upped the ante with the lever.

Found a longer lever (say about 3') - the previous one was around 18" with the fulcrum point about 1/2" away from the pressure point. Also found a bigger bloke to work the slide hammer!

One of us using full body weight on the lever and the other using the slide hammer, it finally yielded.

BTW, each time the lever / hammer was used, the head was firmly clamped to a heavy steel workbench.

The head may have warped with all this treatment as it now shows a small dip in the centre on one of the diagonals of 1.5 thou. The other diagonal and the four edges have zero gap anywhere. Maybe it was always there, I can't be sure as when I first checked for flatness some weeks back, the head was not as clean as it is now. Any which way, this isn't an issue.

The pre combustion chambers are still stuck in but at this stage I haven't decided if I will remove them or otherwise. I'm pretty sure they will come out if I decide to remove them .

Some pictures of the electrolysis bath process and of the injector parts.