Rawze.com: Rawze's ISX Technical Discussion and more
C7 making oil - Printable Version

+- Rawze.com: Rawze's ISX Technical Discussion and more (http://rawze.com/forums)
+-- Forum: Big Truck Technical Discussion... (/forumdisplay.php?fid=1)
+--- Forum: CAT, Detroit, and Other engine related Help... (/forumdisplay.php?fid=72)
+--- Thread: C7 making oil (/showthread.php?tid=4768)



C7 making oil - tree98 - 07-08-2019

2006 C7 Acert 300 hp. All stock 150,000 mi. 15,000 hrs. Fuel in the oil, I'm thinking it's injector cups. How do I test for that? If it is, The head is probably junk right? I doubt CAT still sells new heads for this thing so do I need to buy an entire new engine?


RE: C7 making oil - Unilevers - 07-08-2019

could be alot of things, but they definatly still make new parts for this engine. Check out the HEUI fuel/oil system they have alot of issues.


RE: C7 making oil - tree98 - 07-09-2019

Well, I put dye in the fuel filter and ran it for about two minutes. I shined the UV light on all the injectors and everything looks exactly the same. What dye do you use? Mine doesn't seem like enough of a contrast to be able to see it very well.I shine the light on new motor oil and it looks just as yellowish green as the damn dye! So anyway I think the fuel is getting into the oil inside the HEUI pump. I'm going to replace it I guess and see.


RE: C7 making oil - tree98 - 07-10-2019

Is it even possible for fuel to get into the oil inside the heui ?


RE: C7 making oil - DVT873 - 07-10-2019

Most C7's have a fuel lift pump on the back of the HEUI pump. Fuel could leak in from there. Two rails in the head, one for fuel and one for high pressure oil. Separated by o' rings. If it is an o'ring issue it is usually putting oil into the fuel because oil pressure there is always at least 400 plus psi. Fuel pressure from lift pump usually only about 100 to 120. Look on you tube for adept ape. He has a lot of CAT info.