743 leaking fuel lines

[warrenoliver]

This thing is kicking my butt. Original problem was fuel issues once I changed the glow plugs and put it all back together. After bleeding the fuel lines, I had trouble starting and once running, it had very little power. I used an IR thermometer to determine one of the cylinders were not firing. I found a loose connection on the fitting at the fuel pump which allowed diesel to seep out of the fitting instead of opening the injector. Once I tightened it up, she runs much better. The problem I am having now is that it is still hard to start when cold and I am getting fuel leakage on top of the pump around the injector fittings. I can't see which fitting is leaking. I am going to take the fittings off again and tighten each one again. What is the trick to getting these to seal right? I tried to make sure the fuel line is aligned correctly and seated before tightening the flare nut. I am afraid to crank too hard on the flare nuts thinking I may damage something. What is the trick here? Thanks in advance for your help.

 

[todderwater]

I had a similer issue with a 743B, with the Kubota v1702, when cold it was hard starting and also there was a fuel leak somewhere at the injector pump. the leak on mine was not at the fuel line fittings,(it sure looked like that was the culprit though) but on the adapter the fuel lines attach to. I replaced the o-rings and the little brass washer directly under the adapter (on the top of the spring) and the leak and the hard starting problems were fixed.

 

[antfarmer2]

I had a similer issue with a 743B, with the Kubota v1702, when cold it was hard starting and also there was a fuel leak somewhere at the injector pump. the leak on mine was not at the fuel line fittings,(it sure looked like that was the culprit though) but on the adapter the fuel lines attach to. I replaced the o-rings and the little brass washer directly under the adapter (on the top of the spring) and the leak and the hard starting problems were fixed.

Good call Todder ......I would also check the little wheel there that is a bleeder valve and not a fuel shut off make sure it is closed after bleeding and if you take the wheel all the way out there is a little oring in there too mine was bad and the dealer said they could not see one in their books so I bought the whole valve for 30 bucks problem solved then I took the old valve apart and low and behold there was a two cent oring