Community Forums

2 Stroker · 12-02-2016, 05:42 PM

I have a C-9 2005 motor in a 2006 Country Coach, has any one had oil pressure that has pegged the dash gauge at 100lbs psi on a cold start. Looking at my Silverleaf at cold start the pressure is 127lbs so I use the block heater for about 2hrs to get the pressure under 100 on a cool day. After it warms up going down the road it runs 45-48psi at 1600rpm and idles 25-30psi.
Cat tech say, cold startup pressure should be around 87psi above 100psi could blow the oil filter apart.
So my question is has anyone replace the oil pump to solve this problem or replace the relief valve in the filter head. I have had this problem as long as I have had the coach going on 4 years.
Thanks for any help on this.
2 stroker

cptdzl · 12-02-2016, 05:57 PM

Haven't had that issue but I would check with a master gauge first to see if the oil pressure sending unit didn't fail. once actual pressure verified you can proceed from there. a sensor would be an easy fix. good luck.

2 Stroker · 12-02-2016, 06:56 PM

Rick
Thanks for the reply. I think most coaches have 2 sending units, 1 that the coach builder installed and 1 that the motor builder installed. I have looked at both coming from 2 different places and they both read the same. Country Coach oil pressure sender 0-100 psi vdo and Cat installed one that the ECM reads (Silverleaf) and they both move together. The one on the dash will stay at 100psi until the oil gets warm and then they both move down together.
2 stroker

tropical36 · 12-03-2016, 09:55 AM

Quote:

Originally Posted by 2 Stroker

Rick
Thanks for the reply. I think most coaches have 2 sending units, 1 that the coach builder installed and 1 that the motor builder installed. I have looked at both coming from 2 different places and they both read the same. Country Coach oil pressure sender 0-100 psi vdo and Cat installed one that the ECM reads (Silverleaf) and they both move together. The one on the dash will stay at 100psi until the oil gets warm and then they both move down together.
2 stroker

Assuming that both systems aren't being fed by the same sensor, as you say, are you using the proper oil viscosity for your climate zone?
We're always in the warmer climates and have been using Rotella 15W - 40, with no issues that I know of.
Just for the heck of it, why not replace one of these sensors, just to see what happens.

GreaTOne65 · 12-03-2016, 03:11 PM

2 stroker, aren't you the one that advised me to switch to 10W30 because of this problem of over pressurizing the system? Any way, I did switch to 10W30, and the pressure at start up has never been over 90 lbs. so I've felt the switch was a good move.

Dale

2 Stroker · 12-03-2016, 07:11 PM

Quote:

Originally Posted by GreaTOne65

2 stroker, aren't you the one that advised me to switch to 10W30 because of this problem of over pressurizing the system? Any way, I did switch to 10W30, and the pressure at start up has never been over 90 lbs. so I've felt the switch was a good move.

Dale

Dale
You are right I did say that, the problem is that was close to 2 years ago and I had 9 gallons of oil on hand for an oil change and I may just switch to a 10w30 or Delo 400 LE Synthetic SAE 5W-40. I don't like switching brands of oil all the time.
I will be replacing the oil sender to the ECM.
2 stroker.

Tha_Rooster · 12-04-2016, 11:52 AM

Mine does the same thing since new.

2 Stroker · 12-04-2016, 01:02 PM

Quote:

Originally Posted by Tha_Rooster

Mine does the same thing since new.

Rooster
You have high oil pressure from the get go. What kind of numbers do you see and what grade of oil are you running. Just thinking of switching to Rotella T-6 5w40 or Delo 400 LE Synthetic SAE 5W-40.
akeyzoo here on the forum had the same problem and had his pump replaced, now he has 85psi at a cold start.
2 stroker

tropical36 · 12-04-2016, 01:23 PM

Quote:

Originally Posted by Tha_Rooster

Mine does the same thing since new.

Now, ya got me really wanting to pay attention and with starting up again, later this week. Especially when we're in a cooler climate at present.

2 Stroker · 12-04-2016, 02:00 PM

Quote:

Originally Posted by tropical36

Now, ya got me really wanting to pay attention and with starting up again, later this week. Especially when we're in a cooler climate at present.

This just one I have found
Caterpillar - C9 Engine that keeps blowing oil filter seals - Online Community
I going to do something maybe switch oil to see what happens.
2 stroker

GreaTOne65 · 12-04-2016, 02:01 PM

I have only put 5,000 mi. on my coach since that conversation with 2-stroke, but what 2-stroke and I discussed made sense to me, so I tried it. Since the newer cars have come out using oil, I only thought was only good for sewing machines, I stopped worrying about it, also my Grand Cherokee diesel recommends 5W30!? Many years ago, every one ran 30-40-50 weight oil, but with the new synethic oils it seems as though all bets are off.

Tha_Rooster · 12-04-2016, 03:43 PM

Quote:

Originally Posted by 2 Stroker

Rooster

You have high oil pressure from the get go. What kind of numbers do you see and what grade of oil are you running. Just thinking of switching to Rotella T-6 5w40 or Delo 400 LE Synthetic SAE 5W-40.

akeyzoo here on the forum had the same problem and had his pump replaced, now he has 85psi at a cold start.

2 stroker

I use rotella 15-40 I get around 50 starting it will go up to 100 at 1,200 or more rpm if I don't let it warm up a little or use block heater. Doesn't take long to run normal I'm getting ready to put her up for the winter I think I'll try 10w-30 rotella this time.

2 Stroker · 12-04-2016, 05:51 PM

Quote:

Originally Posted by Tha_Rooster

I use rotella 15-40 I get around 50 starting it will go up to 100 at 1,200 or more rpm if I don't let it warm up a little or use block heater. Doesn't take long to run normal I'm getting ready to put her up for the winter I think I'll try 10w-30 rotella this time.

Thanks for your reply. The BH is just about ready to go back to a 5er. I told her, whats a few more thousand $$$$$$$$

2 stroker

Sportech · 12-06-2016, 08:18 AM

I have the same problem on my C-9. Gage and digital oil pressure show the same. If I start it when the temp is in the 40's, it will go over 100psi even on slow idle. The block heater helps but what you really need to do is heat the oil. I installed 800 watts of heater pad on the bottom of the oil pan. This makes a significant reduction in time to get the oil warm. I also switched to Rotella T6 5W-40 which reduces cold startup pressures by 10 PSI. I figure that it's also better for the turbo bearings.
My normal startup procedure is to start the generator and turn on the block and oil pan heaters. By the time I have removed the the wheel covers and stowed any other gear I have brought with me, I can start the engine and not have to worry about blowing the oil filter. If I'm parked at a campground I turn on the heaters first thing in the morning. I mistakenly left the heaters on over night and and the engine temps were about 130*.
Hopefully next year I won't have too many MH expenses and I'll get the pump replaced. I still hate to pay $150/hour at the CAT shop when the truckers only pay $100.

Dave
07 Revolution 40E
Re-modeled interior!