Can anyone point me in the right direction with this 700 Series PErkins 4 Cyl.

It idles super rough. I changed fuel filter, bled... When cracking the injector lines it will smooth out for a few seconds and then Idles rough again. It idled rough before changing the filter. Do I need to bleed more, do I have air getting into the fuel sys? Please help.

Thanks.

Brian

I am no diesel mechanic, but it sounds like it is loading up, and when your crack the fuel line, and it smooths out, then that tells me it needs more air. Make sure your air filter is clean, and then look at new injectors, or cleaning them to see if there is something holding them open.

Does it smoke at idle?

I changed the inner and outer Air filters. The water separator was full of gunk. That has been cleaned and reassembled, I adjusted the valves. It is idling a bit better. I need to correct myself, before when I stated that it would smooth out when injector line nuts were cracked, this is when they were cracked at the pump end. When cracked at the injector, I just loose the cylinder.

Strange... Do you still think it needs more air? Got any advise for cleaning the injectors?

Thanks.

Have you changed the fuel filter as well as the water trap? If not, do that for sure. I suppose your pump could be bad, and needing rebuilt. If it sucked a lot of junk in it, then it could be messed up. I suppose there is a way to test that, but I don't know how. I would tend to think that the injectors might be the issue. Make sure your air way is clean and clear. I suppose you could start it without an air filter on it, and see if it runs better. If it does, then get new filters.
I am not sure how to clean injectors, or if you can even do that. Might check with a diesel mechanic on that one.

Does it start up fine? if it does I would think your Ip should be fine. Its probably a injector problem. Im not sure about that engine but on my IH I took the injector apart and cleaned them and they were plugged up. On the tip there is 4 tiny holes and I could take a can of parts cleaner and the hose would fit in the injector nozzle and I could see it was plugged. A tiny wire fixed the problem.

Also take a can of wd-40 and spray around the injector while its running and look for bubbles, if they leak you will loose compression.

If there is gunk in the fuel filter that doesnt sound good, Id clean everything I could on the fuel system. On my 484 I put clear injector return lines on it. I kept getting bubbles in them, then about a month later a fuel line blew out on me. After I fixed the line no more bubbles. If you can put clear fuel hoses on it and watch for bubbles. I wouldnt trust the cheap hose forever but once you get it running good Id change them.

Sounds like fuel pump should be looked at check pressure rate,and for leaks also may just be wore out to the point its dumping fuel too. And if you have done valve work it could just be a timing thing too. Talk to a case dealer they usually have someone that does their pump and injectors i always found pump rebuild and reman injectors help a lot

Does it start up fine? if it does I would think your Ip should be fine. Its probably a injector problem. Im not sure about that engine but on my IH I took the injector apart and cleaned them and they were plugged up. On the tip there is 4 tiny holes and I could take a can of parts cleaner and the hose would fit in the injector nozzle and I could see it was plugged. A tiny wire fixed the problem.

Also take a can of wd-40 and spray around the injector while its running and look for bubbles, if they leak you will loose compression.

If there is gunk in the fuel filter that doesnt sound good, Id clean everything I could on the fuel system. On my 484 I put clear injector return lines on it. I kept getting bubbles in them, then about a month later a fuel line blew out on me. After I fixed the line no more bubbles. If you can put clear fuel hoses on it and watch for bubbles. I wouldnt trust the cheap hose forever but once you get it running good Id change them.

Clear hose, that is good advise. I'll try that.

have you got it yet. when you loosen the fuel lines to injectors, you remove fuel to cylinder(lean out) my guess is gunk in injectors, more than likely not going off at desired pressure. injectors can try cleaning, but if you found gunk in filter it may have got thru to inj and took out, maybe time for new injectors. take carb cleaner to inj lines to clean-out then spray with WD40, diesel or light oil to protect them.

Assuming that the compression is good in the engine pull the injectors and take them to a local injection shop will be able to test your injectors for you to see how they are. That is the easiest and first step to do. Once the injectors are known to be good then move onto the pump. You mentioned some dirty filters. How long has this equipment been sitting? It is possible if it sat over the winter with water in it then you have some things sticking and will need rebuilding. If you can’t find a shop near you give us a call.

Mark