A few ??'s with pics for the Pros that know more than me

[cheap bronco]

Hello All, let me start by thanking everyone in advance who helps me and responds to my questions. I have built many gas engines from scratch, this is my first diesel one. I picked up this '89 7.3 for a swap into my '88 bronco, and figured its best to reseal it now than later in the vehicle. Upon dissasembly I encountered a few questions. I have pics uploaded pics, just havent figured out how to add caption under each one. Engine is pretty clean inside no sludge inside the heads

1. Upon removing the log headers, some of the header bolts were full of engine oil, is it normal for these engines?

2. There is a small piece of piston missing from piston number 2 on the passenger side, is this from high EGT's?

3. Piston #7 on drivers side has a exhaust valve mark on it, my guess is that who worked on this motor before installed the wrong length pushrod. Dont know.

4. I purchased a Felpro head gasket set and I want to do the valve seals, one thing Im confused about is that the intake side seals are rubber and the exhaust seals are somekind of hard plastic. Has anyone used these in the past and are they good?

5. There is still crosshatch marks on the cylinder walls, the previous owner said the engine has 160k, I would imagine the crosshatch have dissapeared by now, or does the engine have less miles?

6. From looking at other pics of motors on this site, Im statring to see I might have a 6.9. The valve cover said it was a 7.3, can i still reuse the stock head bolts?

Thanks again.

 

[typ4]

it could still have crosshatch. oil presure valve could be stuck causing the piston kissing.
Piece missing could be it passed a glow plug tip or overfueling.

if the block is also gouged, very bad, kinda of a bad pic for asessing

 

[riotwarrior]

very clean inside the valve cover, I would think a GP tip would have done a little more ratta tat tat all over the top of the piston myself...but what do I know...??

Can't say for sure, maybe pull that GP and see if in ok condition? try to get another pic in focus and lets have a closer look, it's symmetrical from what I see which indicates some sort of debri was ingested or left in there.

 

[flareside_thun]

I've run across 1 and 3.....I deemed 1 as normal. As for 3, I have had no problems with those type of seals this far.....I've noticed that the crosshatching tends to stick around awhile on these. Easiest way to distinguish the engine (maybe) is by the size socket you used to remove the headbolts.

 

[cheap bronco]

Attached are 2 more clear and different angles of the piston with a chunk out of it. I just checked I used a 1/2" drive 1/2" socket to remove the head bolts. Are they reuseable, hope so.

THanks,

 

[cheap bronco]

sorry guys, they look clear on the camera, I dont get it.

 

[flareside_thun]

IIRC, 1/2 inch means it's a 7.3......headbolts aren't meant to be reused as they are meant to stretch....but, myself and others here have reused them with success. It's you discretion.

 

[icanfixall]

Well lets start by welcomeing you to the forum. Now I can explain what engine you have. Most definatly its a 7.3. The proof of this is several things in your pictures. The pistons are shaped differantly in the 6.9 flame trench. The 6.9 pistons have a squared off flame trench in the piston. The 7.3 has the tear drop like what you piced. The siz of the head bolt hex heads are 5/8 inch for the 7.3. The 6.9 is either 1/2 inch hex or 9/16.. The bolt diameters are 1/2 inch for the 7.3 and 7/16 for the 6.9. Now look at the top of the block on the drivers side of the injection pump gear cover. There is a stamped set of numbers there. It will say either 6.9 or 7.3 in the sequence. Post the numbers and possibly we can tell you what year the engine is. Now the engine you have pictured is from a van so... Thats going to mean some parts needs to be changed for this engine to fit a truck. Both headers on the oil cooler will need to be changed. Look at the front header. It will need to have 4 bolts in it for the truck application. A van has only three bolts. The oil pan dip stick is longer because the engine was in a van. The drivers side exhaust manifold will need to be changed for a truck application. The van manifold wont fit a truck. The passenger side manifolds are all the same. My thoughts are the engine you have was from a 92 or 93 van by the serpentine belt pulleys I see. But the po could have updated an early V belt pulley setup too. Finally, the pistons.. The pics are really bad but... They look like they got really hot and burned off some of the edges. It would be best if you removed all the pistons and checked the top ring for free movement. That much heat can soften the piston crowns enough to stick the rings. Sorry for that news but its best to look it over weel before you try to run it only to find out its not a well engine. The cross hatch marks stay around for many miles too. Remember we burn a oil for fuel so the pistons are well taken care of plus... We have an oil jet under the pistons at the bottom of the cylinders. It sprays oil under the pistons to help cool them.

 

[rjjp]

High EGT by those last 2 pics, it's a 7.3 and it's out of a van judging by the oil dipstick. Serpentine setup didn't come around until late 92, but someone may have swapped that on.

 

[typ4]

keep tearing into it that piston with the valve kiss could havea bad rod bearing also.

 

[gandalf]

Good write-up, Gary. Here is a picture to help locate the engine number you're referring to. It isn't always easy to find, frequently buried under a layer of grease. Notice I had to wipe it clean. Be aware you cannot always see the entire number, as the sealant sometimes spreads over the first digit or two. In the picture look to the lower right area for the number.