Community Forums

Arch Hoagland · 01-02-2013, 10:52 PM

EngineerMike said
"Arch- I had a Ford oil pump that over pressurized the oil filter. Made a helluva mess. Oil pumps are usually gear pumps, so called "positive displacement" pumps, i.e. when the gears trap & move oil- the oil is going to move come hell or high pressure. So they have a bypass internally or externally. If the bypass is clogged or partially clogged you get over pressure, and the weak link is the filter (usually the o-ring, sometimes the can). I would suspect the bypass was out of spec on the rig you mentioned."

You're probably right but it's interesting that the Toyota filter handled the pressure where the aftermarket filters both blew out right away. I put about 100,000 miles on that Toyota and never had a problem using or burning oil.

Pellerotto · 04-04-2013, 12:16 PM

Thanks to everyone who responded tony original post. I just wanted to update the situation. There was one core plug that had corroded to the point of failure. My mechanic who I found through allof this ( who I will continue to use) advised that the other plugs were starting to corrode. He changed them all. I have put on a good 2000 miles since then which included a great trip to Fort wilderness. I am planning on changing the oil in another 2-3000 miles and have it analyzed.

MJFZ · 04-04-2013, 03:23 PM

Quote:

Originally Posted by gemini5362

I am going off topic a bit to ask you a question or dieselbeaver whomever might know. I have the 2005 400ISL cummins engine. I experienced problem with overheating when I went out west during the early fall. I went to a freighliner dealer with a seperate RV service center. They replaced the FAn Controller and the problem lessened but still seemed to get warmer than I thought it should on the way back. The weather had cooled off considerably by the time I started back home so I did not get a test of the repairs in hot weather. I noticed one of the posts on IRV2 where someone mentioned that up through early 2006 ISL engines this was a problem but that they corrected it on the later 2006 engines. Do you by any chance know what they did that corrected the problem.

Thank You

You might want to check with Freightliner factory customer service. The cooling system is provided by Freightliner. In 2005 I do remember Freightliner had issues with side radiator hydraulic driven fans. Not sure if your coach is side radiator.

Mike

dieselbeaver · 04-04-2013, 11:24 PM

Gemini,

I agree with checking the cooling package for blockage. It doesn't take much loss of efficiency to push a marginal system over the edge as it were.. I have seen one coach, I think it was a Freightliner chassis but the long and short of it was that the hydraulic pump was eating itself and causing a lack of performance in the fan motor. Check and see, but I think Souce engineering makes a Hyd fan control kit if that turns out be the issue.. I think it's been mentioned here that the electrical control of the fan motors can be problematic. Also remember that fan motor is also pulling/pushing air for the charge air cooler and elevated intake temps can also #1 bring about a derate from the ECM, but they can also raise the engine temp as well. Good luck.

Allen.

gemini5362 · 04-06-2013, 02:33 PM

Quote:

Originally Posted by dieselbeaver

Gemini,

I agree with checking the cooling package for blockage. It doesn't take much loss of efficiency to push a marginal system over the edge as it were.. I have seen one coach, I think it was a Freightliner chassis but the long and short of it was that the hydraulic pump was eating itself and causing a lack of performance in the fan motor. Check and see, but I think Souce engineering makes a Hyd fan control kit if that turns out be the issue.. I think it's been mentioned here that the electrical control of the fan motors can be problematic. Also remember that fan motor is also pulling/pushing air for the charge air cooler and elevated intake temps can also #1 bring about a derate from the ECM, but they can also raise the engine temp as well. Good luck.

Allen.

Allen thank you for the advice. When the problem started I had it checked out by a freightliner repair center that had an RV specialty shop. They replaced the hyrdaulic fan controller so hopefully the hydraulic fan is ok. I have researched this on the web as well as I can. I found that when the problem started one of the fixes was to put 15w40 motor oil in the hyraulic system instead of hydraulic fluid. The thought was that the hyrdaulic fluid was getting too hot and thin to drive the fan properly. This was not done on a recall but on individual units under a warranty repair. When the motor oil was put in the hydraulic system something and I dont remember what it was ruptured from over pressure because of the thicker oil. I bought the bus used so I do not have a record of anything that has been done to it under the warranty. I was worried that one of the things I was going to have to do was get the oil fix and replace what ever ruptures from it. I have a good warranty that is good for two more years so I want to get that resolved this summer. I was checking fluids getting ready for a trip this week and I noticed that on the hydraulic tank there is a sticker saying fill with 15w40 motor oil. I am assuming based on the sticker the warranty work might have been done already. Ichecked the hydraulic resevoir and it was filled with hydraulic fluid so I am going to call freightliner and check with them about draining the hydraulic fluid and refilling it with oil.

This might all be for nothing it could be that the repair work done by the freighliner repair in sacremento fixed the problem. When they got done the weather had started cooling off so I did not get into the hot summer issues I had faced earlier. I have noticed that after they replaced the controller that my coach temperature goes up and down no matter how small a hill I climb and that is even in 70 and 80 degree weather. I am going to see about refilling the hydraulics with oil and then go from there.