L245 Misfire

[b350]

Hello all. I have a L245DT that has a misfire on the middle cylinder. Its gravity feed to the injection pump and I have eliminated fuel delivery as a problem. When I crack the lines at the injectors I get fuel from #1 and #3 but massive amount of air from #2. The air never bleeds out no matter how long the line is open. Line to #2 does not leak and the line holds a vacuum. My question is can an injection pump put air into line? Also the pump with all lines off only spurts fuel about 2 to 3 inches out of the pump. Is this normal? the amount of looks to be consistent for all three outlets. I have experience with gas engines but none with diesels so I would be grateful for any help.

 

[007kubotaguy]

Check to be Sure the delivery valve on #2 is tight. This is the part that the injection line attaches to on top of the pump. It take a 19 mm wrench. If it lose that cylinder will misfire. The center one is hard to check. You can remove the clamps holding the injector lines together. Remove the injector line from number two injector. Then you can slide a box in 19 mm wrench Over The Line down to the delivery valve to be sure it's tight. Good luck.

 

[b350]

Check to be Sure the delivery valve on #2 is tight. This is the part that the injection line attaches to on top of the pump. It take a 19 mm wrench. If it lose that cylinder will misfire. The center one is hard to check. You can remove the clamps holding the injector lines together. Remove the injector line from number two injector. Then you can slide a box in 19 mm wrench Over The Line down to the delivery valve to be sure it's tight. Good luck.

Thanks. The center one did come loose when first took the line off but I disassembled it more so that I could get it tightened back up.

 

[North Idaho Wolfman]

Thanks. The center one did come loose when first took the line off but I disassembled it more so that I could get it tightened back up.

Did you put all the parts back into the pump correctly?
If with all the lines off it's putting out fuel out of all pump ports at the same heights then the pump sounds fine.
A damaged injector can cause it do odd things.

 

[b350]

Did you put all the parts back into the pump correctly?
If with all the lines off it's putting out fuel out of all pump ports at the same heights then the pump sounds fine.
A damaged injector can cause it do odd things.

I didn't take the pump apart I just disassembled the lines so I could retighten the delivery valve that loosened when I was taking the line off. I took the injector apart and cleaned it but didn't find anything obviously wrong. It made no difference in the amount of air coming out at the injector when the line is cracked open. Open to all suggestions, thanks.

 

[North Idaho Wolfman]

If your getting air pumped out of the injection pump, that is a first for me, never seen that.
So you getting no fuel out, or just bubbly fuel?

 

[b350]

I didn't take the pump apart I just disassembled the lines so I could retighten the delivery valve that loosened when I was taking the line off. I took the injector apart and cleaned it but didn't find anything obviously wrong. It made no difference in the amount of air coming out at the injector when the line is cracked open. Open to all suggestions, thanks.

"a damaged injector can cause it to do odd things" You're exactly correct. I took the #2 injector apart again and some dummy (me) put the pushrod in upside down. Reassembled it correctly and the system bled out fine and ran good for about 10 to 15 minutes at around 900 rpm. Suddenly, massive knock and misfiring again but this time it's #1. A lot of air that won't bleed out. This one is assembled correctly so I think I'm going to throw a set of injectors at it to see what happens. Original problem was random misfire/ loss of power.

 

[b350]

Okay, update. Replaced the injectors ( oregon fuel injection) and I still have a misfire. The tractor starts easily and idles fine but between 1200 and 1800 rpm there is a miss. It goes away above that range and works ok. Is there anything other than the injection pump that could cause this? I should mention that the compression is low at 350-360 but above the minimum spec of 327. Doesn't sound like a compression issue but I just thought I would put that out there.

 

[North Idaho Wolfman]

Okay, update. Replaced the injectors ( oregon fuel injection) and I still have a misfire. The tractor starts easily and idles fine but between 1200 and 1800 rpm there is a miss. It goes away above that range and works ok. Is there anything other than the injection pump that could cause this? I should mention that the compression is low at 350-360 but above the minimum spec of 327. Doesn't sound like a compression issue but I just thought I would put that out there.

Have you adjusted the valves?

 

[b350]

Have you adjusted the valves?

The only adjustment I made there was to back off on the compression release adjusters to make sure they weren't interfering with the valves when hot. Didn't think valve adjustment could be an issue but I'll try it if you think it's possible. Thanks.

 

[b350]

The only adjustment I made there was to back off on the compression release adjusters to make sure they weren't interfering with the valves when hot. Didn't think valve adjustment could be an issue but I'll try it if you think it's possible. Thanks.

Adjusted the valves (all loose) and no change. Still misfires at 1200 to 1800 Rpm.

 

[North Idaho Wolfman]

Adjusted the valves (all loose) and no change. Still misfires at 1200 to 1800 Rpm.

Do a compression test, that will tell you which route you'll need to look next.

 

[utterchaos]

Do a compression test, that will tell you which route you'll need to look next.

Adjusted the valves (all loose) and no change. Still misfires at 1200 to 1800 Rpm.

 

[utterchaos]

Long time reader and learner on the forum…..first time poster .
I have the same machine, I don’t have the problem but curious If you resolved this in case I encounter the same.