Rusty Injector

[Charlie]

I have a Yanmar 4JH4E. The two forward most injectors were a bit rusty when I pulled them out. The two aft ones were fine. I used Chief Engineers method of penetrating oil and patience. It didn't take too long.

I don't know the name of the hole where the injectors are placed but it has a coating of penetrating oil and rust in it now.

The injectors are the type that seat with a clamp to hold them in place. It seems to me that I should clean the rust out of the injector hole. My concern is getting any of the rust into the cylinders. I have a couple of ideas and wanted to run them by you guys:

1) Easiest. Place the piston at TDC and use a product called EVapo Rust to fill the hole and then vacuum out the liquid when done. (Evapo Rust link Evapo-Rust rust remover description page )

2) Medium. Machine a plug for the bottom of the injector hole that will plug anything from going down the spot for the injector nozzle and do same as above with the piston at LDC.

3) Hardest. REmove the head and clean it without the head on the block.

4) Other. Use a bore cleaning kit for a shotgun and clean it that way.

Please comment on which idea you think is sufficient and include WHY.

[Charlie]

Bump anyone have an idea.

[sdowney717]

It seems to me that I should clean the rust out of the injector hole.

Why??
I would say 5) reassemble as is.
The penetrating oil dissolves most of the problem rust.
Just put it back together.

1) Evapo Rust put in the cylinder ? sounds bad idea.

2) Machine a plug for the bottom of the injector hole ? bad what if it gets stuck

3) Hardest. Remove the head and clean it without the head on the block.?
Yes best is this, only way to guarantee you dont put grit in the cylinders

4) Other. Use a bore cleaning kit for a shotgun and clean it that way.
loose bits of rust or pieces of brush falling into the chamber, this is something you have to decide if it is worth doing.

[gjordan]

Dont use a vacuem cleaner on a flamable substance. You could have a very loud and hot surprise. Since your injectors are not screwed in you might find corks to plug the holes and then a small brush to get rid of most of the rust, Then blow clean with some compressed air. Find out why they are rusty? Cockpit sole leaking, leaking hoses, under the Galley sink line? You dont want to fix it again a year later.____2 cents worth._____Grant.

[Ex-Calif]

Put the injector back in the hole. Use a mild solvent, brushes etc to create a "slurry" - high pressure air to blow it clean and dry.

If you don't have an air bottle - go buy a couple of cans of keyboard air at the computer store.

In hindsight you should have cleaned it all up before removing the injectors - next time do this procedure first.

If there is any chance of anything falling into the combustion chamber clean first.

[Charlie]

Originally Posted by Ex-Calif

Put the injector back in the hole. Use a mild solvent, brushes etc to create a "slurry" - high pressure air to blow it clean and dry.

If you don't have an air bottle - go buy a couple of cans of keyboard air at the computer store.

In hindsight you should have cleaned it all up before removing the injectors - next time do this procedure first.

If there is any chance of anything falling into the combustion chamber clean first.

Ex Cal I cleaned the head above the injectiors. Nothing will fall down from there. There was rust on the injector body that welded the injector case to the wall of the hole that the injectors case sits in.

If I put the injector in then I can't clean the hole.

[Charlie]

Originally Posted by gjordan

Dont use a vacuem cleaner on a flamable substance. You could have a very loud and hot surprise. Since your injectors are not screwed in you might find corks to plug the holes and then a small brush to get rid of most of the rust, Then blow clean with some compressed air. Find out why they are rusty? Cockpit sole leaking, leaking hoses, under the Galley sink line? You dont want to fix it again a year later.____2 cents worth._____Grant.

I do need to find out why they are rusty. There is very little visible rust on the head. I would be vacuuming out mostly water so I wouldn't worry. But I could blow it out too though that would create a mess.

Originally Posted by sdowney717

Why??
I would say 5) reassemble as is.
The penetrating oil dissolves most of the problem rust.
Just put it back together.

1) Evapo Rust put in the cylinder ? sounds bad idea.

2) Machine a plug for the bottom of the injector hole ? bad what if it gets stuck

3) Hardest. Remove the head and clean it without the head on the block.?
Yes best is this, only way to guarantee you dont put grit in the cylinders

4) Other. Use a bore cleaning kit for a shotgun and clean it that way.
loose bits of rust or pieces of brush falling into the chamber, this is something you have to decide if it is worth doing.

Evapo rust is a great product and would eat up the rust quickly. I'll have to think about $5. Don't like the idea of putting together a rusty item though.

[Ex-Calif]

Originally Posted by Charlie

Ex Cal I cleaned the head above the injectiors. Nothing will fall down from there. There was rust on the injector body that welded the injector case to the wall of the hole that the injectors case sits in.

If I put the injector in then I can't clean the hole.

In that case I vote trying to jimmy something up to block the hole (flat washer taped up with something to pull it back out) coupled with TDC and high pressure air to blow it out afterwards for good measure.

Easy to comment remotely without seeing what you are up against but be careful not to get something stuck in the hole - but you knew that....

PS - If you use air can spray with a little nozzle tube make sure you hold on to the tube with your spare hand while spraying - wouldn't want to shoot the tube into the cylinder - yikes - LOL...

[Charlie]

Finally came up with a new idea. Took a dowel and wrapped the end with wads of Never Dull. Then I took some thread and tied it tightly to the end of the dowel. From there I used it like a bore cleaner from a shotgun. Cleaned up most of the rust. I assume any bits of the fiber will get burned up in the cylinder.