I am having trouble with my JF 550G with bubbles in the filter killing engine. I changed filter and pump. Still having the problem. I drained all of the diesel and took off fittings but could not get screen to come out to clean. Is there any trick to removing these screens?
I meant to say John Deere 550G dozer.
Those screens will collapse and bend over time if they're clogged up with gunk, and often there is so much stuff stuck in the nylon screen they don't want to pull out. By the way, I think they screw out if you didn't already know that. Takes a flat blade, I used to have an old one that started out wider than the hole and I ground the sides down until it would just slip inside the threads. If you get it out, throw it away and if you're worried about it put an inline filter just off the fitting there. Or buy a new one from Deere, up to you. I'm working from 30 year old memories, so if I'm steering you wrong, apologies!
Thanks, I'll give it another go.
Still didn't work. Any ideas what could be causing the bubbles?
Plugged screen??? combined with a leak somewhere of course, but I'd bet that it won't suck air if it's not pulling a vacuum on the plugged screen. Did you see the slots for a straight screwdriver to turn it out like lantraxco described? If there's a big enough opening in the center, stick a pin punch through it and either push the screen off, or push it enough to straighten it out. You're on the right track. I'd hate to do it but you could drill it out if you can't get anywhere removing it, or cut down a hacksaw or sawzall blade and cut through it enough to loosen it up.
Also, if it doesn't screw in, take an o ring pick and use that to hook it and pull out. If the dealer is near enough, buy a new screen and that will make it more clear how it comes out.
I got the screen off. Ran it about 20 minutes and it still got bubbles in the fuel filter. Any other ideas?
Presumably you have the old style glass box filter, replace it with a new one, those rubber grommets are good at leaking. But that filter is on the pressure side of the transfer pump?!? Take the lines apart, check for good flow, blockage, and then blow them out with air, the lines on the dirty side of the filter that is, don't touch the lines between the filter and injection pump. The priming lever on the transfer pump is great for checking if the lines are blocked and where, the lever feels different if it's pulling a vacuum vs pumping fluid vs pumping air vs pumped up. The transfer pump is minimal pressure (less than 5psi?) but it sounds like something is still plugged up somewhere.
I do have the glass box filter and I changed it but it still gets bubbles. I blew out the fuel line from the tank to the pump when I changed it out but that did not fix the bubble problems. If seems that since I changed the pump out I am getting more bubbles than before. These JD's with the glass filter are a pain in the u know what. My dozer is in Louisiana though I live in Texas. I will try everything you suggest next time I am back in God's country (Louisiana). I will one day retire in LA.
You could try applying air pressure to the fuel tank and look for a leak. I just wrap a rag around my blow gun and put it in the fuel filler cap.
I'll give that a try.
Deere is also famous for using a rubber seal at line fitting joints. Those seals go bad over time and sometimes leak air but not show signs of fuel. As mentioned, airing up the tank a bit will usually find the leak.