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Recent content by MurphHeavyMech

  1. M

    CAT 3126B Issues

    Pic of fuel in the sight tube and of my fuel pressure right before the head. I didn’t get a video or pic of the fuel injection actuation pressure. That was bouncing in a range from 400-1600 psi. I talked to Cat Tech support and they said that it shouldn’t do that. I put a manual gauge in the oil...
  2. M

    CAT 3126B Issues

  3. M

    CAT 3126B Issues

    I followed CAT guidelines to a t with sealant from Cat for the sleeves. Everything I replaced was OEM from Cat. I suppose it could be a rolled ORing on installation but since it has the same issue as before I tore it down and replaced everything, I find it hard to believe. I’ll try to get some...
  4. M

    CAT 3126B Issues

    Fuel return check valve was replaced. I’ll have to rig up a gauge between secondary filter and the head
  5. M

    CAT 3126B Issues

    I appreciate everyone’s advice. All o rings, injector sleeves, injectors and the heui pump were new from CAT. I won’t be back to work on it for a couple days but had a random thought about the fuel pressure sensor. With it being partially plastic, I’m wondering if it could be the culprit letting...
  6. M

    CAT 3126B Issues

    No fuel racks on it. Injectors are all electronically controlled on this one. We have an IT62 Cat loader with a 3126 that is the MUI system. It has the racks on it. We had to have the Cat tech there to adjust that one and replace the injector sleeves on it cuz we didn’t have the tooling to do...
  7. M

    CAT 3126B Issues

    I searched the other posts multiple times looking for something similar. Didn’t locate anything. The foamy fuel is what baffles me also. I want to think it’s something simple but I’m unsure. Kinda makes me rethink how good of a mechanic I am. Only been working on diesels engines and heavy...
  8. M

    CAT 3126B Issues

    The injectors get their fuel from a common passage in the head. I did use a clear tube tool that I purchased from Cat between the tank and transfer pump to eliminate the possibility of air leaking in the hand pump and fuel/water separator housing. Perfectly normal red diesel there. When I used...
  9. M

    CAT 3126B Issues

    I have a 3126B in a Cat D5N that I’m stumped on. Boss just got this machine. He had a CAT tech throw ET on it about a month ago. Tech said heui pump was bad. So now it’s my problem. Engine was puffing black smoke and misfiring. Erratic rpm. Since then I have replaced the heui pump, fuel filters...
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