Well I finally got the time I needed to start tearing down the engine in my diesel rig. I have to retrieve a glow plug tip, and also inspect for any damage that may have happened when the glow plugs burned out (WAP 080s). The last time it failed to start, it fell into an uneven cranking pattern, indicating low compression in one cylinder, I hope I'm wrong.

If all is well, I will drop the heads back on, and get some head studs while I'm at it, if I see any damage or anything that makes me uncomfortable, I will rebuild it completely. Wish me luck guys, I'm going in........

 

good luck.

 

Have tools, wish I could travel.

 

Thanks guys, and thanks for the offer Dave. I've got one head stripped down just need to rig up a hoist to lift it now, should know more by tomorow.

 

Looks like I'm headed for a rebuild. The intake valve in the #1 cylinder made a cute little circle on the Piston. I'm not sure what caused this, but I have a feeling I am going to find out, somehow I don't think it was the GPs. The #1 cylinder also had the lowest compression, at only 400-410 psi when tested, with all others at 450-500.

So far two of the glow plug tips seem to have been "passed" with the #7 glow plug making some gouges on top of the #7 piston. Two glow plugs, #3 and #5 were already burned out (though not distorted), and were removed without incident.

I have not pulled the passenger head yet, will keep you posted............


PS, STAY AWAY FROM WELLMAN GLOW PLUGS!!!!!!!!

 

Well, other head is off. The Fire rings in the head gasket for #2 and #8 cylinders were both failed, this certainly explains why there was coolant sludge on the front of the block near the thermostat housing. It looks like some combustion gasses also found their way into the crank case by sneaking in around some of the push rods, exess blowby mystery also solved.

At least I've got some answers, block gets pulled tomorow.....

 

I recently had to tear down my 6.9 to replace a piston. I am a gas rig man and this was my first diesel experience. I stripped the motor completely down to the block and re sealed the whole thing. I did not disturb the other pistons or the mains. The number one piston cracked in half from the wrist pin bore up across the top. Strangest thing I ever saw. Still dont know what caused it but she seems to have accepted the donor piston with no problems. I really enjoyed the experience, except for the price for gaskets. Good luck on your rebuild.

 

Thanks poooch. I'm not sure how far I'll take this rebuild, but I will go as far as a feel I have to to make sure I will not have to go through this again any time soon.


Well, the block is out, piston #7 has obvious signs of glow plug damage, and on closer examination, as many as 4 cylinders may have been in the early stages of head gasket failure. I'm probably lucky #7 is still in one piece (and no, I am not superstitious, at least I wasn't....).

Theres something demoralizing about a truck with an empty engine bay .

 

With Fords, it's best to take the engine out every 10-20 years to clean the accumulated gunk off the frame

 

Sounds like you made some good progress!

Good luck with the rebuild.

 

Yeah its pretty filthy in there, all the blowby that had built up lately was causing every gasket to weep slightly, of course the valve covers always make the biggest mess.

I'll start to tear into the block either today or tomorow, can't wait to see wat other supprises there are. One thing that really struck me about this engine, is that everything is just MASSIVE, the heads, the block, and the space between the cylinder bores is also very large. Although the head bolts were a little skimpy , We must do something about that .

Will keep you posted.......

 

OK, I got a chance to check the glow plugs in the other head. All were retrievable, but the three WAPs were of course fried, and two did not come quietly, had to use vice grips. The 4th GP on that side (#2 cylinder) was a beru, and it still works.

So just for the record, it looks like the odds of passing a glow plug tip out the exhaust safely are 1 in 2. Cylinder #1 passed without a problem, #7 has mashing on it, with all other plugs coming out in tact. What is really frightening about this, is that the tips popped off without being disturbed, just burning them up did the dead, and since the engine was run immediately afterwards, well you know the rest....

 

Unless the pistons are cracked, I see no need for a complete rebuild. Your compression numbers seem pretty good?

Rebuild the heads, and bolt her back up for another 100K's of service??

 

so my question is what happens when motorcraft glow plugs are no longer for sale. where does that leave us? is this what we are going to have to look forward to?

 

What is so special about motorcraft glow plugs? i been using champion plugs last 10years and never had any proplems..


Ot sorry..