Injector o-rings

[taterthedog]

I was having some rough running and oil consumption issues so I decided to change the injector o-rings. I was getting a cyl contribution code for #7 so I pulled that one first.
http://powerstrokearmy.com/photopost/data/536/medium/IMG_0025.JPG
#s 1 and 5 were ok but 3 was like this:
http://powerstrokearmy.com/photopost/data/536/medium/IMG_0029.JPG

I didn't pull out the other side yet. Here's a question...With the bottom o-ring gone like that, what will happen? It can't really go anywhere except in the injector cup right?

 

[96stacked&smoken]

It most likely got super heated and burned up

 

[DEEZUZ]

get a picture of the copper on the bottom. I would check fuel pressure, that kind of looks like what happens when the injector are actually sucking in fuel because they are not being supplied enough, IE weak pump.

 

[taterthedog]

get a picture of the copper on the bottom. I would check fuel pressure, that kind of looks like what happens when the injector are actually sucking in fuel because they are not being supplied enough, IE weak pump.

I'll get a picture of the coppers as soon as I get a chance. May not be till Wednesday, got to work next 2 days. I'll rig up a fuel pressure gauge too, that's a good point.

 

[TrailerHauler]

Those o rings are toast. I'm also wondering what kind of shape the copper washer is in. I can't recall for sure but I think those bad bottom o rings are causing your oil to bleed past the injector, hence your oil consuption.

 

[907DAVE]

Fuel cannot go anywhere as long as the copper crush washer and lower oil o-ring are intact.

 

[golfer]

the bad lower o-ring has no contact with HPOil..

the diesel fuel enters the injector in between the lower & middle o-rings...and the HPOil enters the injector between the middle and upper o-ring.

don't think your picture shows any explanation for oil consumption...any fuel leaking past the lower o-ring will still be contained by the middle o-ring and copper washer.

also, with no carbon on the lowest third of the injector...the copper washer was intact and doing its job of preventing combustion coming up out of the cylinder and burning the exterior of the injector body.

here's a picture of what it would look like with the copper not crushed properly (though these are 6.0L injs)

 

[taterthedog]

the bad lower o-ring has no contact with HPOil..

the diesel fuel enters the injector in between the lower & middle o-rings...and the HPOil enters the injector between the middle and upper o-ring.

don't think your picture shows any explanation for oil consumption...any fuel leaking past the lower o-ring will still be contained by the middle o-ring and copper washer.

also, with no carbon on the lowest third of the injector...the copper washer was intact and doing its job of preventing combustion coming up out of the cylinder and burning the exterior of the injector body.

here's a picture of what it would look like with the copper not crushed properly (though these are 6.0L injs)

View attachment 6125

Thanks,
That's pretty much exactly what I was thinking.

I changed the o-rings on the even bank last night. Some bad lower o-rings but pretty much the same as the other side. All 8 copper washers looked great and no evidence of combustion gases leaking up to the injectors. I'm going to do a compression test next.

 

[golfer]

Thanks,
That's pretty much exactly what I was thinking.

I changed the o-rings on the even bank last night. Some bad lower o-rings but pretty much the same as the other side. All 8 copper washers looked great and no evidence of combustion gases leaking up to the injectors. I'm going to do a compression test next.

I would suggest firing the engine, and letting it idle for a few minutes prior to just plopping the injs back in and running a compression test...

the oil/fuel on the piston (or in the bowl) will give you a false (high) reading if you don't actually RUN the engine for a few prior to running the compression test...

I wouldn't even worry about fully bolting the VC's back on...just a couple of bolt to keep the oil splash down...

 

[taterthedog]

Roger that. :thumbsup:
Thanks golfer.

 

[taterthedog]

Finally got the gear together to do a compression test. It's not looking promising. #7 was giving a contribution fault and it only had 110psi compression. It also sounded different. The rest of the numbers are on the low side too.
#1-280
#2-305
#3-260
#4-280
#5-300
#6-300
#7-110
#8-305
This was a dry test, I'll do a wet test when the batteries charge a bit.

 

[taterthedog]

Did a wet test on a few cylinders, compression came up to 360 to 390, then the check valve started to stick on the compression tester so I cleaned it up and decided that I wouldn't bother testing the rest, since it wasn't my tool. It was also getting late in the night. Not sure where I'll go from here, I'll probably button it up and run it as is till I decide.

 

[BigAlsPSD]

Did you get the opportunity to check #7 again?

 

[taterthedog]

Did you get the opportunity to check #7 again?

Nope, did 6 and 8, since I was on that side. #7 sounded funny too. I might see if we have a borescope at work to have a look.

 

[taterthedog]

Just got around to doing a wet compression test on cyl #7. Still at 110 psi. Not sure what I'm going to do next. I think I'll put it back together and run it as is. Maybe pick up an engine stand on vacation next month and pull it out and strip it later. Right now I need the garage space for other things.

 

[BigAlsPSD]

Hate to hear that...

 

[taterthedog]

Not the end of the world. It was working pretty good beside the oil consumption and a bit of blue smoke. If my new IPR takes care of the fueling issue I was having, i'll still drive it back and forth to work. Should make for an interesting project after that. Kind of looking forward to tearing into it really. I would start now if I had a bigger garage.

 

[taterthedog]

Buttoned the truck back up recently. Changed the IPR, fuel filter and oil and filter. Had to put in Rotella 15w40 because Ford had no Motorcraft 15w40. Truck ran pretty good. Went for a pretty good burn to get most of the air out. Gotta rig up a gauge no to check fuel pressure.