How To Pull The Heads On The 673

[ThaddeusW]

OK I got to the engine again today. I removed the front water manifold (proper term?) and began to pull the injectors. The No.1 injector is kinda rusty, but it came out without much effort. The intake valve for the No.1 cylinder does appear to be open so I guess it has seen some water. The No.2 and No.3 injectors look decent and came out by hand once I pried them loose. I sprayed a good amount of PB into each injector hole to get things loose.

Now my question is how do I properly remove the heads? Do I remove the rockers, and if so is there a right and wrong way to do so? Those springs look tough and I don't want them flying off. What about the push rods do they come out and easily go back in? Once I loosen the head bolts the head should come right off correct?

Picture time:

Head with injectors and valve cover removed:

Injectors, in the order in which they were in the engine from left to right.

Now the injectors do come appart right? I see a hex on the top part and the lower part has two flats to hold the injector as you unscrew the top. Also I am guessing that it doesent matter where each injector goes as far as cylinder number as they all look the same. There was no washer between the injector and head only a cloth or paper seal.

[terry]

OK I got to the engine again today. I removed the front water manifold (proper term?) and began to pull the injectors. The No.1 injector is kinda rusty, but it came out without much effort. The intake valve for the No.1 cylinder does appear to be open so I guess it has seen some water. The No.2 and No.3 injectors look decent and came out by hand once I pried them loose. I sprayed a good amount of PB into each injector hole to get things loose.

Now my question is how do I properly remove the heads? Do I remove the rockers, and if so is there a right and wrong way to do so? Those springs look tough and I don't want them flying off. What about the push rods do they come out and easily go back in? Once I loosen the head bolts the head should come right off correct?

Picture time:

Head with injectors and valve cover removed:

Injectors, in the order in which they were in the engine from left to right.

Now the injectors do come appart right? I see a hex on the top part and the lower part has two flats to hold the injector as you unscrew the top. Also I am guessing that it doesent matter where each injector goes as far as cylinder number as they all look the same. There was no washer between the injector and head only a cloth or paper seal.

The cloth or paper seal is only a dirt/dust shield, there are copper washers that go on the bottom of injector to seal combustion, they are probably stuck in the injector tube, in the head. Terry

[ThaddeusW]

The cloth or paper seal is only a dirt/dust shield, there are copper washers that go on the bottom of injector to seal combustion, they are probably stuck in the injector tube, in the head. Terry

Ahh so they are toward the tip of the injector you mean.

[terry]

Ahh so they are toward the tip of the injector you mean.

They are around the tip on the flat spot on the injector bottom. Terry

[Lmackattack]

To pull the head remove the rockershaft, evenly lousen the bolts to relive the valve spring tension. pull the pushrods out and undo the head bolts. If everything is removed off the intake or exhaust it should come off. Or if your "old school" you can pull both heads off with the Intake, exhaust still bolted to the heads ...just bring a hoist and pull the top of the engine off in one pice !

[ThaddeusW]

Thanks guys. Everything is coming off smoothly but I think the exhaust manifold will be a whole different story. Some studs look like someone smashed them so ill have to try and cut the ends off. Hopefully I can get them off this weekend.

[MACKS]

Keep the push rods in order so you can put them back the way they came out, the injectors should have numbers stamped on them for the cyl. they go to.

[ThaddeusW]

Keep the push rods in order so you can put them back the way they came out, the injectors should have numbers stamped on them for the cyl. they go to.

Ah so the injectors do have a certain order. I would have thought that it didnt matter since they all do the same thing.

[terry]

Ah so the injectors do have a certain order. I would have thought that it didnt matter since they all do the same thing.

Have seen alot of macks overhauled and never seen the push rods or injectors put back in the same cylinder. When you get a new injector it is not numbered according to the cylinder, you can ream the injector tube out with a special reamer, put a new washer on injector tip and your good to go. Also the two nuts that hold injector does not torque that tight, don't have the specs. in front of me right now. Terry