Fuel Injector service

[Reefgeorge]

Any advice on who to use for fuel injector service once I remove them from my MAN mechanical 8's?

Thanks,

George

 

[Boatsb]

Ask Derek (avenger)

He knows about that kind of stuff.

 

[Nick]

Derek is the man!

 

[Mike36c]

Here on the East coast Diesel Injection of Martin County are the best. Ask for John, (772) 283-8999

 

[Reefgeorge]

Here on the East coast Diesel Injection of Martin County are the best. Ask for John, (772) 283-8999

Thank you, I will give John a call.

George

 

[Reefgeorge]

Anybody taken MAN injectors out? Most people are talking about collars with retaining bolts into the block that you remove after the fuel lines come off. These look more like a collar ring around the injector that threads into the block that needs a spanner of some sort.

Thanks,

George

 

[Avenger]

Could be a bolt down clamp or collar. Usually it's a hex, but knowing the Germans it could require a special tool. Post a pic and I'm sure we can figure it out.

MAN injectors are frequently frozen in the head because their owners are proud and wash the engines. No kidding. That's caused more heartburn than you can imagine.

 

[Reefgeorge]

Could be a bolt down clamp or collar. Usually it's a hex, but knowing the Germans it could require a special tool. Post a pic and I'm sure we can figure it out.

MAN injectors are frequently frozen in the head because their owners are proud and wash the engines. No kidding. That's caused more heartburn than you can imagine.

Funny you should bring that up as I am overdue for some engine room clean up. Better leave the garden hose in the cockpit.

Next time I go down there I'll get some pictures of the fuel injectors.

 

[Reefgeorge]

It appears that the injector is held down to the head with a threaded collar ring that looks like a castle nut on top. So I would think that a special socket with spanner nubs slides over the injector to engage the retaining ring and unscrews it while you hold the injector body in place at the top with a wrench on the two flats just under the fuel line threads. Simple enough, but then I read the instructions in the service manual and it sounds more complicated than that:

Remove pressure screw from the fuel injector using a pin spanner

For this purpose use a ring spanner with a fixing screw

Where injection nozzles are more accessible, screw inertia extractor on to nozzle holder and knock out nozzle holder

Take out injector and injector seal.

What does all this sound like to you? Whats going on with that two wrench set up?

Thanks,

George

 

[Reefgeorge]

I have ordered this specialty tool set that I hope is the correct "socket" for injector removal.

George

 

[dottieshusband]

Well, I don't know a thing about MAN stuff....but a "screw inertia extractor" is a fancy way of saying slide hammer...

 

[Avenger]

It is. I think the other thing they're describing is just a puller. I've been waiting for the MAN tech to get back to me... still waiting.

 

[Reefgeorge]

10-4 on the slide hammer. Iv'e seen a few examples of that tool used with lug nuts or a recycled flare nut welded on

 

[Reefgeorge]

It is. I think the other thing they're describing is just a puller. I've been waiting for the MAN tech to get back to me... still waiting.

Any word yet from your MAN guy?

Thanks,

George

 

[Avenger]

Nothing yet. I put in another call, hopefully he'll check in soon.

 

[Reefgeorge]

Thanks, standing by.

 

[Avenger]

Well that worked much better on the second try. He said that the tool you're showing in that kit on the lower left allows you to use the castle nut to pull the injector. It threads on to the line fitting and then unscrewing the retaining nut should break the injector loose. He also said they can be quite difficult to remove and the tools break a lot. Hopefully you started a long time ago with the penetrating oil.

My advice: if you're going to try to pull them with the retaining nut I'd take the nut out first and put a lot of heavy lubricant like grease or never-seez on the threads to help prevent them from galling. You don't want to booger up the threads in the head.

 

[Reefgeorge]

Thank you for chasing this down. So then it looks like the reason for the two simultaneous wrenches shown in the removal picture is that the top wrench is holding the fuel line fitting attachment in place while the lower wrench is turning the outer sleeve which drives the castle nut up and out? Is that how you understand it?

Do you know why they also use the slide hammer approach?

Thanks,

George

 

[Avenger]

Looks like you've got it. I'd guess they recommend the slide hammer because you can apply force without the risk of stripping the threads. Also, when dealing with frozen components there's a lot to be said for shock value.

 

[Reefgeorge]

Looks like you've got it. I'd guess they recommend the slide hammer because you can apply force without the risk of stripping the threads. Also, when dealing with frozen components there's a lot to be said for shock value.

If you need a slide hammer I guess you immobilize the top of the injector body under the line fitting threads on the two flats and then turn the castle nut up and out, then attach to the line threads and make momentum transfer your friend?

George