I hear you on pumping it with grease or oil but part of me is hesitant. In my mind, either it goes with x amount of effort or the heads come off. If it is stuck so hard then I tend to think that it wont run proper anyway because of significant rust ridge, possible damaged rings...etc. And what about the possiblity of damaging pistons or other? Any thoughts?

much thanks

Don't forget the hydraulic pump could also be stuck. Hopefully some oil in it so it is not, but needs checking before removing heads. Depending how the pump is protected you can use the hydraulic pump drive to turn the engine.


If it comes to head removal, 2 heads so not that heavy. In the good old days remove much the same heads from RD 7 with 2 people no hoist.

Yes that is how I feel Neil. I mean, if i put a ton of pressure on the piston then am I going to wreck a ring land, crack a piston or...? May as well just get at it and lift the head, have a look at the liners, see if it is feasible to soak/ heat the piston and push it down or just pull the whole assembly. Sometimes it seems to me (my friend included) they are allergic/ scared to death of opening up the engine. Id rather do some surgery than wreck stuff or free it up and have it run like dog crap anyways. I think I will try with my buddy to get some oil in the injectors or cylinder ports, try prying it and if it wont go with reasonable effort, then its time to get at it. 

Is it much effort to get the injectors out on these old D8800 engines?
 

Mangoman . The stuck cylinder will be the one with the exhaust valve open. Use a pry bar and push down on the valve and slip the pushrod out.
I have used the hydraulic pressure from a farm tractor with success. Simply find a suitable adapter to screw on the injector line fitting and pressurise through the injector. Put a chalk mark or other on fan or flywheel to record movement . Remember to apply compression release before turning engine over . Some of the engines I have done in this way have started and are still running with no problems . Others have suffered stick rings and needed the head lifting off and the piston lifted out to replace stuck rings . Obviously not what you do on a machine that you intend to do 20000 hours with over the next few years .

Hi Team,
rubber mallet works well to see if the valve/rocker springs back or not, or from memory you may be able to give the rocker a gentle lift with a bar under the push rod side of the rocker arm-- the engine inlet valve de-compressor system would lift said valve rockers if none were stuck--only needs one to be stuck for the operating system to not function--check the operating lever to see if it is not able to travel thru its full movement range to the full decompress position. If a valve were to be stuck fully open then the de-compression system would appear to work correctly so be careful to check that any full open inlet valve has free movement.

If any accessory (water pump etc.) is stuck you will get movement at the flywheel with rotation ,back and forth, within the range of gear backlash in the accessory drive train.
You would need to remove an injector and make a suitable adapter to use the air or grease gun method.

NOTE :- that as said above you can generate some 10,000PSi pressure with the grease gun which can be enough to split a liner or such as this pressure would be way in excess of expected designed pressure limits from combustion pressures.

Cheers,
Eddie B.

Easiest first step is to pull the injectors and get some penetrating oil to the cylinders. Let soak and do the pry bar thing as edb mentions.

the methods i suggest are only to get it turning over you would then rebuild the engine. with new liners bearings etc.
to use the grease method you remove the heads.

i know the soak with diesel and love tap idea works we freed an engine doing just that.

yes good info....baby steps and time..apply diesel above and let soak....and pry gently to get movement...

did this with a gasoline welder that was supposedly pristine....runs good after much #@%$&** ......i can't say, describe with this being a family program....