Medium and Heavy Trucks
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Hi I'm Wayne
I will help you with this
did you replace the Cam Bearings
let me know
That is the biggest over looked item
I will send this to another Cat expert
Thanks for asking your question. I will try and help you out.
I would like to ask you a few questions first about your problem. I hope that is ok.
May I ask why the engine was overhauled? Did it have low oil pressure before the overhaul?
Can you tell me how much was cut off the crank? Do you know the part numbers of the rod bearings?
Was the oil cooler housing and relief valve replaced during the overhaul?
Thanks for the information.
.51mm or 0.020 thousands rod bearings are the correct ones if only 0.020 was taken off the crank. That's the correct part number (128-0395) for 0.020 Undersized.
These engine have a known problem of low oil pressure caused by the relief valve in the oil filter base. It gets worn and sticks open. When this happens. Both the oil cooler or filter housing base along with a new relief valve must be replaced in order to correct this low oil pressure problem. It sounds like your problem judging by the psi readings you gave earlier. I would definitely suspect this first.
The next thing I would want to check is the piston cooling jets. I have seen one of them get knocked off after an overhaul because it is bent. When they get knocked off, the oil pressure will drop.
Please reply back if you need more help. I am happy to assist.
Yes you are correct. Its in the filter base. The reason they have a problem sticking open is the C13 KCB produces a lot of soot in the oil form the IVA's. This soot gets in the valve area and causes wear. Once it wears, it begins to stick open.
Since all the cooler nozzles are in tact and the plasti gauge readings looks good. I must suspect the relief valve in the filter base. You may also want to inspect the pick up tubes in the oil pan as well. I have seen them crack and suck air.
On another note. I know that 12 psi sounds low. But the minimum allowable psi at idle hot is 10 psi.
Let me know if you need more help.
Thanks for the information. Yeah I have not had much luck with a spring either. I would look into the relief valve. If it was not replaced. I would definetely replace it. I have put many of them in for low oil pressure.
Yes that is correct.
One more thing. You may also want to check for leaks around the Iva housings. I would get the engine warm to when the pressure drops. Then remove the valve covers and unplug the injector harness. Then crank the engine and look for leaks. I have seen the Iva housings have large leaks and cause low oil pressure.
Ok sounds good. Let me know how you make out.
Hey. I just wanted to see how things were going. Please let me know if you need more help. I am happy to assist. If my information was helpful, please leave a good or higher rating so that I receive credit. Thanks.
No problem. Sorry you did not see anything. The good news is the oil pressure readings you currently have are within specs. As long as the oil pressure does not drop below 10 psi at idle. You should not have any problems.