Hard to Remove Injector

[bodywash]

I am trying to replace an injector on my 84' JD 850. The old injector is proving impossible to pull out. I have tried threading a 6in bolt into the top of the injector and using it as a sort of slide hammer with a 5 lb weight. Still no luck. I am getting very frustrated. I would appreciate any and all suggestions. Also, I am not worried about saving the old injector - just need to get it out.

Thanks Scott

 

[bodywash]

Thanks Dave,

The injector on this tractor does not thread into place. Rather it seems to be a friction fit - and it has a removable bracket with two bolts holding it in place. I have removed the bracket, now just trying to litterally pull the injector out of the cylinder. So any advice is welcome - even if it means destroying the injector.

thanks

scott

 

[mark777]

Scott, your right they can be a real pain.

What we do is saturate the base of the injectors with good quality penetrating oil, let sit over night and fit the appropriate end wrench on the flats of the injector. Strike the wrench with a large shot filled hammer and shock the injector loose.

We also shop vac around the base after the injectors are 3/4's of the way out to make sure no debris falls into the cylinders.

Good luck, Mark

 

[Dargo]

I have never changed the injectors on a tractor, but I have on a Cummins diesel. I had one injector that just would not come out. The Cummins diesel have a little detent that holds the injector in place and keeps it from turning. Apparently this one had gotten turned a little. Until I managed to get it aligned with the detent it wouldn't come out. After soaking it for literally days with WD40, I managed to get it turned the 1/16 of a turn or so to line it up. Then I still had to rig a slide hammer setup to get it out. Once out, I found that I didn't even damage the injector. I didn't have to worry about it either way, as I was putting in some slightly bigger injectors. /forums/images/graemlins/cool.gif
Good luck with yours. You may want to check to see if there is a little ball detent setup like I had on the Cummins. If so, it sure made a difference for me getting it out.

 

[RoyJackson]

"We also shop vac around the base after the injectors are 3/4's of the way out to make sure no debris falls into the cylinders."

That's a good comment...

Injectors and glow plug threads tend to get sooted up from unburned fuel.

Never had to pull an injector from a tractor, but have done it on a few Mercedes.

Penetrating oil and patience..also, try tightening them a bit first. Sometimes, that helps break 'em loose.

I see the original poster mentioned a "friction" fit. Not sure about this due to the higher pressures in a diesel engine. If the service manual isn't avilable, a trip to a dealer's service dept. might be worthwhile.

The injectors I've seen had at least a few threads to hold them in place... Doesn't mean that's the case here, but it's worthwhile to find out.

Good luck!

 

[CMunger]

When replacing the injector coat it with Never-Seeze, and it will come out effortlessly next time.
Chuck M.

 

[bodywash]

Thanks for the reponses.
On this injector, there is a bracket that fits over the top of the injector - bolted down with a stud on either side of the injector- to keep the injector in place.
I have a replacement injector assembly - and there are no threads. I also purchased a shop manual - basically the operation is to remove the lines, remove the bracket, and pull out the injector. Suggests using a puller if needed. The stud posts on either side of the injector make it impossible to put a wrench on the injector to turn it.
The fuel return line threads into the top of the injector. I have replaced that small bolt with a 6 inch long bolt (this bolt is only 8mm) and have used a 5 lb weight on it as sort of a slide hammer to try to jolt the injector loose. No good so far. I will continue to try penetrating oils. Also, I was thinking about unscrewing the top off the injector assembly then taking it to a welding shop to maybe have a larger diameter and longer shaft attached to top end of it. Then using this assembly as a larger and heavier duty slide hammer. Hope this does not sound too crazy. Just hope I do not have to spend my winter going out to the barn and beating on my tractor every nite just to remove an injector. This seems like it sould not be so hard.

Thanks again for all your help

Scott

 

[alvanko]

Try this..............
Reinstall the retaining bracket but leave it loose . Crank the engine over . The high compression of the deisel should "push" it out . I have never tried this have been told it will work .Soak it good with PB Blaster the night before.

 

[normde2001]

I was going to suggest the same as alvanko. The Yanmar injectors mount the same way and that's what has been suggested. Ditto on the "PB Blaster".

 

[CMunger]

This is not uncommon to have injectors rust in the head. I have seen it to where the head had to be removed to get it out. The puller the manual tells you to use probably works with the studs that are there. Again install the new one coated with Never-Seeze and this will not happen again.
Chuck M.