Ford 4500 Diesel complete rebuild startup question

[Grown_in_gravel]

Bringing up my 4500 backhoe for the first time with:
-New Crank, rings, pistons, bearings etc.
-Valves reground and reseated
-Rebuilt Generator
-New filters all the way around (fuel, oil, power steering)
-New injector tips and tested for proper leak down and release pressure

After lots of starter issues, I got it running. After running out of fuel due to a plugged petcock, cleaning out the tank and rebleeding it, it now smokes slightly and seems to have low contribution on #1. I determined that by cracking open the injector line at the injector and it had much less change in RPM than cracking one at a time the other two injectors. I pulled #1 injector out and it passes leak down and has a good pattern. I've got some ideas but wanted to toss it out there for the group to comment on. Here is a link to the video of it running before tank plugged & running out of fuel.

PS. Cant figure out how to lube the throughout (release) bearing. It's got some sort of threaded on grease pot. Barely a mention of it in the service or operators manual.

Comments/flames welcome.

 

[shaun wallace]

For throwout brg, unscrew cap , fill with grease, screw back on.

 

[ErnieD]

You really want to work it to seat the rings. Vary engine speed as you work it. If you can get dyno time so much the better. Piston rings resonate against the cylinder walls and you want to change the pattern, hence the varying engine speed. Retorque the head bolts. Does it miss on one cylinder at cold start up? Compression test and flipping injector location would be next steps.

 

[Grown_in_gravel]

You really want to work it to seat the rings. Vary engine speed as you work it. If you can get dyno time so much the better. Piston rings resonate against the cylinder walls and you want to change the pattern, hence the varying engine speed. Retorque the head bolts. Does it miss on one cylinder at cold start up? Compression test and flipping injector location would be next steps.

Thanks for the suggestion. It does miss until its warmed up, varying the engine speed did improve the skip. I'll retorque the head bolts (hadn't thought of that). I was wondering if I messed up a valve lash but probably not. I'll swap the injectors next, don't have a compression tester for a diesel. I may need one or at least cobble up an old injector (force the pintle to stay open, etc).

 

[Texasmark]

I was reading on here not too long ago about doing a valve job on Ford Diesels. Seems that the distance that one needs to do a valve job under normal machine shop practices, increases the volume of the cylinder and even though it seems to be miniscule, it apparently has an effect on compression making for hard starting and lower than desired compression. When you run that compression test post it on here and let the knowledgeable folks comment on it.

One thing that could lead to errors would be engine temp and whether or not the rings have had time to seat (wear in). I overhauled my 3000 30 years ago ( inframe....PO had disconnected rubber hose between the air filter and inlet manifold...bottoms were ok. You wouldn't believe the condition of the top of the pistons....requiring replacement.... including the area around the upper compression ring...... and the machine shop did the head like they would rework any head and I haven't had any kind of a problem with the engine since......starts right up on these winter mornings and pulls plows as I expected it to so.......that's what I know about it. Good luck.

 

[Bern]

I was reading on here not too long ago about doing a valve job on Ford Diesels. Seems that the distance that one needs to do a valve job under normal machine shop practices, increases the volume of the cylinder and even though it seems to be miniscule, it apparently has an effect on compression making for hard starting and lower than desired compression. When you run that compression test post it on here and let the knowledgeable folks comment on it.

One thing that could lead to errors would be engine temp and whether or not the rings have had time to seat (wear in). I overhauled my 3000 30 years ago ( inframe....PO had disconnected rubber hose between the air filter and inlet manifold...bottoms were ok. You wouldn't believe the condition of the top of the pistons....requiring replacement.... including the area around the upper compression ring...... and the machine shop did the head like they would rework any head and I haven't had any kind of a problem with the engine since......starts right up on these winter mornings and pulls plows as I expected it to so.......that's what I know about it. Good luck.

You are correct - valve recession (depth from valve face to cylinder head) can make a big difference in the compression ratio and consequently affect the ability to start on cold mornings. A good machine shop knows this however and will make sure the depths are within spec. Incorrect head gasket will do the same thing.