Hi everyone, I'm new to the forum but could sure use some suggestions on a problem. I purchased a cat 318bl with the engine knocking. We took everything apart & found the number 6 rod bearing destroyed, so we replaced the crank & rod, had the head gone thru, rebuilt the turbo & had the block checked & honed. We reassembled with new bearings, rings & gaskets, the engine started right up & sounds great but was smoking, we were told the rings need to seat. So we have ran it for about 20 hours now & the problem is not any better, in fact it seems to be getting worse because now when we put the machine under load the low oil pressure light comes on & off & the throttle is surging. I have now been able to track the machines history a little bit & found that it was sold at an auction to the guy that I purchased it from. The auction listed the machine as having blow by, the guy I got it from only ran the machine about 3 hours & I guess that was when it ate the bearing. I have talked with the engine shop about the issues since I think something was over looked now knowing the blow by issue, they don't really have any idea what could be causing the problem & before I tear everything back down I would appreciate any in put. I would like to add that we completely removed the turbo & exhaust manifold & ran the engine & it appears to be smoking from every cylinder. Sorry for such a long post but I'm stumped. Thanks in advance for any in put. Steve
Put mechanical gauge on the engine and verify. Oil pump replaced, bypass stuck? Bearing not installed correctly or clearance ??? Smoking, rings idled at low operating temp for 20hrs? Misaligned/cracked rings or valve guides/seals.
What is your serial number? Hi I agree with Doylex you need to confirm engine oil pressure.( should of been done at original start up) have you checked your pump timing? did you check piston height when you assembled the engine? did you have head work done? Are you sure the timing gears are set correctly? Did you match the markings on the rods with the marks on the pistons, Are the rods installed the right way what type of fuel system does it have inline pump or rotary? Mark
Did you plastic gauge the main and rod bearings?
Sorry for not responding sooner but I had responded & for some reason it never showed up. If this shows ok I will enter some more details. Thanks
G'day, No expert but one experience I had was where rings were replaced, ie compression rings and oil scraper rings were not. Source of trouble then. Were ALL the rings replaced? Was bore tolerance measured as even with new rings could be worse than old carboned rings that let only so much by??? Just a thought, Regards, MX45
AND one time had problem with low oil pressure and was cracked pick up pipe!