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Sonny7thb · 03-28-2023, 07:21 PM

2001, Fleetwood discover cat 3126 B. Developed a leak in the high pressure, flexible, oil line that goes from the bottom of the Huey up to the cylinder head. Has quick connect fittings, because space is limited. Cat doesn’t show that it even existed. Went to Freightliner, they laughed at me. I did borrow some JIP (not sure if that’s the correct acronym???) from a local hydraulic shop. Figured out some fittings that would work and they made a hose to get me back on the road. Problem is, with this setup, it’s going to rub and eventually leak again. I’m going to have a second one made up and carry as a spare unless someone can give me a better solution………

bigb56 · 03-28-2023, 08:04 PM

I have a HEUI Navistar and the high pressure hoses were improved by making them extra thick, then sleeved in plastic corrugated conduit to help with abrasion. Of course they still make mine so that doesn't help you, but still others have done what you have done and had new lines made at a place like Flodraulics or Hose Power. Can you take the old one to one of the shops and have a new one made just like the old one that will not rub? If it's the same as mine they are STC (snap to connect) connectors and available everywhere. Secure it and sleeve it in something? One thing about the STC connectors, make sure everything is clean or they might not seat all the way. Everything will look good till one blows off and dumps all your oil. The new ones have a red ring at the fitting so you can tell when it's fully seated.

Sonny7thb · 03-29-2023, 07:05 AM

Thanks Brian. I will start looking for a source for the STC fittings and once I find a shop with them, I will get the proper hose made. Thanks again
Sonny

bigb56 · 03-29-2023, 07:44 AM

The STC trademark is owned by Eaton and they are still under the Aeroquip name. To separate them they make a tool which is simple to make from a piece of thin steel or an old stamped wrench.

Sonny7thb · 03-29-2023, 05:44 PM

Quote:

Originally Posted by bigb56

The STC trademark is owned by Eaton and they are still under the Aeroquip name. To separate them they make a tool which is simple to make from a piece of thin steel or an old stamped wrench.

yep, figured the tool out pretty quick I had an old long open end wrench that i had "thinned down" and it worked great to get the old line off.

Skip426 · 04-03-2023, 01:59 PM

The high pressure oil HOSE , was replaced by a steel line with angle fitting as a running change ( up ) .
Not sure what year this happened , but my 1999, 3126B had had it done prior to my purchase of the coach in 2010.

Skip426 · 04-03-2023, 02:12 PM

BTW: The oil return to the pan plumbing changed about as often as I change my socks ; but for better access to the fitting at the bottom of the HUEI pump , the tinerman nut ( green arrow ) can be removed and the electrical component of the IAP solenoid can be slid off the shaft , after loosening the drain tube at the yellow and moving it in the direction of the red arrow.
That's what I had to do to mine to replace the failed O ring on the lower fitting.
Second picture.

Skip426 · 04-04-2023, 10:12 AM

I made several mistakes, in my previous post ; with acronyms and component names .
This pdf on the 3126B HEUI , fuel injection system ; particularly page 13-14 will help with names and function of the systems part names and function.

The picture is the wrenches I modified to get the fittings off to replace the split O ring.

Sonny7thb · 04-04-2023, 05:18 PM

Thanks Skip 426. That was very, very enlightening.
I also modified a couple of wrenches to get my new hose on…

dansawyer · 03-01-2024, 08:29 AM

I am looking at these pictures and wondering how you get your engine so clean? Mine is covered in oily soot. The PO had the valve cover tube simpliy running out straight down. I added tubing to bring it out on the passenger side rear corner. Is there another source of oil I should look for? Can I start by using simple green and light water to clean this?

We are starting out on a 5000 mile trip and the HEUI high pressure upgrade is on my list. I suspect mine is original. I am slowly working through the known weak points to help me sleep better.

Thanks in advance, I sure appreciate your posts. Dan

Skip426 · 03-01-2024, 07:03 PM

Dan; the pictures in post #6 are not of my engine ; simply a couple I hold onto to illustrate the OEM hose and change up tube ; post #7 is of my engine and YES it could use a very extensive cleaning.

dansawyer · 03-01-2024, 09:34 PM

I haven't gotten past trying to clean the radiator and the CAC.

Back to this thread, how tight is the connection of the hose to the HEUI? I have had very bad luck with old fittings. Given the special tooling is it reasonable to assume the lower fitting can be loosened?

I haven't tackled this job yet. I have the replacement steel pipe.
I have heard one of the failure modes is the for the high pressure tube to start to disintergrate and send small particles to the injectors. Replacing the original rubber tube seems like a good idea.

Skip426 · 03-02-2024, 09:23 AM

Dan, I have no experience with the hose , as my issue was with the " O " rings on the angle fitting at the back of the HEUI splitting.

The O ring has a recess in the back of the pump and a washer on the fitting is tightened down to hold it in place ; if the hose uses a similar set up then the torque should be similar to that of the IAP sensor , which is not very tight .

I will check through my pdf on the E engines to see if I can find more info on the hose .

bigb56 · 03-03-2024, 06:22 AM

Quote:

Originally Posted by dansawyer

I haven't gotten past trying to clean the radiator and the CAC.

Back to this thread, how tight is the connection of the hose to the HEUI? I have had very bad luck with old fittings. Given the special tooling is it reasonable to assume the lower fitting can be loosened?

I haven't tackled this job yet. I have the replacement steel pipe.
I have heard one of the failure modes is the for the high pressure tube to start to disintergrate and send small particles to the injectors. Replacing the original rubber tube seems like a good idea.

If you want to be sure use new or rebuilt fittings. At the very least, get everything super clean with a power washer before disassembly as dirt can hinder the STC fittings ability to fully lock. The new STC fittings have a red ring on them that disappears when fully seated, if you can still see the red ring it's not in all the way.