I have a 2007 Cat 257 B with 652 hours. Here's what's going, I've noticed that running it a few hours here and there I'll check the oil and started noticing it lower on the dip stick every time. I don't run the machine very often. It doesn't have water in the oil or oil in the water so I didn't think it was the head gasket problem. It's not knocking & sounds like it's running fine but while it's idling I take the valve cap off and it's puffing white smoke out bad. A few mechanics thought the rings were stuck so they told me to change the oil, flush the engine with diesel & put in new oil with marvel mystery oil. So that's what I did! However I ran it for 15-20 mins not very hard today and the low oil pressure light came on! We did not have a pressure gauge but we did take the quick connect off and turned the engine over and it is getting plenty of oil to the top of the heads. I plan on buying a new oil pressure sensor Monday but does anybody have any suggestions or comments? Anything would be greatly appreciated. Thanks
What do you mean you flushed it with diesel?
Drained the oil, put diesel in the engine to flush out sludge or anything in the engine. I let it drain out for a full day before I filled it up with oil & mystery oil. I did not start the engine with diesel in it.
The mechanics I spoke with thought that the rings were stuck and that diesel might clean up some of the carbon on the rings
Another mechanic told me to take the injectors out and put some marvel mystery oil on top of the cylinders for a day or so then manually turn the engine to get most of the mystery oil out. Any thoughts?
Rather than a new oil pressure sensor, I'd add a mechanical oil pressure gauge. Chances are the old sensor is not the problem and a gauge will verify it. If you mixed half MMM, then that's quite a bit thinner than motor oil, so it wouldn't surprise me to have the low oil pressure light come on, especially at low idle when it's warmed up. What color is the oil? if it's black already I'd change it and add less MMM this time, or none. I wouldn't flush an engine with diesel unless I saw the soot or crud that I wanted to remove, and then be sure there isn't any trapped in the pan, or head, pretty hard to do.
Not the worst thing to try? Are you that desperate yet? If you go to that trouble, I'd skip the MMO (sorry about that last post!) and use some acetone or similar solvent, and add another squirt each day for a week or more, then crank it with the injectors out to clear it out before starting it.
I only put 2 quarts of MMO to the oil. But you might be right because the sensor came on once it got warmed up. I've been using delvac 1300 it says it meets cat ECF3 oil requirements, not sure if actual cat oil would make a difference.
The oil is still pretty clear, but with the oil has only been in there for maybe 45 mins of running. But I could tell it's getting darker every time I've checked it.
Nine times out ta ten when people try to flush an engine it blows up in a short time from lack of oil, oil pump pickup gets plugged with everything that got flushed, I believe there was a change to the crank case breather hose routing on some cats because they would pull the oil through the turbo, might have been a cold weather issue.I find it hard to believe the rings would be stuck at 600 hours.I think it would be a good time to tear it down and fix the problem before you have more pieces than required, you will be saving lots of cabbage leaves in the short term. Overworked
What is the proper oil pressure @ idle & wide open? I'm getting 50 psi at idle when I floor it, it starts gradually going down. I ran it for 30 mins hard and it went down to 5 psi and the low pressure light/buzzer came on. Shut it off then started it back up and it does back at 50 psi.
Mine was doing exactly the same thing at nearly identical hours. It was a head gasket. There is an update gasket for that engine. Ken
Watglen you didn't have any water in you oil or vise versa?
Some of the 257b models had an oil pump suction problem. There was a service letter on it . If your oil pressure is dropping at high idle I would think that the oil is not returning to the pan fast enough and the level is dropping or there is a suction line leak Service letter. PI31269 The oil suction pipe on certain skid steer loaders and multi-terrain loaders may move into the cylinder block and restrict engine oil flow which can cause loss of engine oil pressure. I would need a serial number to see if your machine is affected.
SLK6638. If it had a blown head gasket would that cause a decrease oil pressure?
Ok. Your machine isn't affected by that letter. A blown head gasket should not cause low oil pressure unless it's blown at an oil pressure port.
This one is interesting, op was oil consumption with crankcase blow by, now its low oil pressure, slow drain back makes sense with oil pressure symptoms, was oil level being checked with engine running at the beginning? If oil was being trapped in top end would that cause breather to become suturated with oil then leading to so much pressure?
Been there,its probably the head gasket,you will find it blown from the fire ring into the push rod port causing crankcase pressure.I had the same symptoms with a 05 216b.To check turn the motor over by hand with the oil filler cap off and listen for air escaping as each piston reaches TDC .It was a common problem until Cat changed to an all steel gasket.Over here in Oz it cost $86 for the gasket and a few hours of my time.Its a pretty easy job if you have some mechanical knowledge.
That is mine too.....exactly. Fire was blowing across a burnt section of gasket into the oil gallery. No water in oil or oil in water, just a lot of exhaust blowing out crank vent, and oil fill port. New metal gasket fixed it up.
Thanks guys, I just got all the gaskets, time tear it down, I'll let y'all know
Alright I have a blown head gasket that's for sure. From the back of the machine it was blown in the first piston. However the second push rod is bent. Had a lot of build up on it and bent. Does anyone know what that could be from? The blown gasket goes into the push rod that's bent.
Glad to hear you're getting to the bottom of it. I'd guess the push rod got a little hot from the exhaust and bent. That's a pretty wild guess though. Obviously check that valve for sticking or bending, and check that piston for any marks from foreign object.
The piston & valves look good, the push told that's bent is definitely discolored from the others, like it did get hot. The cat house said one pushrod was $99.82 does that sound right?
Doesn't surprise me. That's one part that I wouldn't hesitate to buy used, if you could find one without wasting $100 of time?
Ask them the Part Number that they are selling for that price. My system shows a 154-1248 pushrod retailing at $7.06 each. Even replacing all 8 push rods would still be only around $60. Have you checked the condition of the ball end on the adjusting screw of the rocker where you found the bent pushrod..? You may find you need to replace that screw also. The Part Number is shown as 153-5587 priced at $.7.65. Note: I'm doing all this without a machine Serial Number. I THINK these numbers are correct but would not guarantee them 100% without a S/N.
It seems to be a common spot for those older type gaskets to blow, at no 1 piston on exhaust push rod side. It seems odd that push rod is bent,if the exhaust valve isn't carbon' d up and sticking, i think Delmer 's guess of getting hot at the breach point is possible . Also i agree $100 is a bit rich, if you can't find used try asv or perkins they might be more reasonable? Depending how long the gaskets been blown you could have carbon particle in the oil filter or pick up, giving oil pressure problems,a good quality 15w/40 and a new oil filter might help.
The serial # SLK6683 The bent pushrod was the only one with a lot of build up on it. Thanks for y'all's help
In that case the Part Numbers above are correct. Your local dealer prices may differ by a little bit to what I quoted above, but not by $7 versus $100 ........
Thanks for the info nige, it was over the phone so he possibly might have looked up the wrong thing. I'm going to go see on Tuesday