The Stovebolt Site Forums The Shop Area Engine Shop My 235 is dying

I have noticed a lot more blue smoke in the last month or so, but when I pulled into the yard Wednesday evening, I noticed that my oil pressure took a dive and the engine sounded "grindy". I shut it down immediatly and checked the oil and for gaping holes in the block. Everything seemed fine and I started it up and watched my oil pressure and everything seemed normal. Yesterday I hooked it to an external pressure gage and ran it at an idle and reved and the pressure seemed notmal, about 32 at idle. I am afraid to drive it now. I need to get my extra engine to a machine shop, but I was hoping to keep driving mine until the other one is rebuilt. I am hoping to just have the machine shop do the bores and check the crank and bearings etc. Can I expect a good outcome doing the assembly myself or are there clearances that need to be determined while the machining is being done that can only be accomplished with the machinist doing the assembly? My brother is a mechanic and will be doing most of the assembly work. How much damage am I doing to the 235 in my truck if I keep driving it the way it is? I was a given a 250 from a 60's model truck that was supposed to be in good running shape, is it worth the time and effort to plant this in my 48 until I can get my 235 rebuilt? Any opinions will be welcomed. Thanks!!
Ralph

Oldtmy, I don't quite understand what is meant by "grindy". Did it start knocking? Or, is it trying to bind? It does sound like you have bad rings or maybe bad valve seals. Can you run a compression check on it? Have your brother bring over his compression tester. But none of that should have caused you to loss oil pressure. When did you last change the oil? Was there any "gold dust" in it? Could possibly have some weak bearings or maybe something wrong with the oil pump or Distributor (for that I suggest talking to the Guru "Chiphead"). But it does sound like it is holding good oil pressure as per your test, so unless you hear some knocking, I don't think you would have a serious problem. Oil pressure will sometimes "fall off" a bit when you come to a stop, especially if the oil is getting old.

Thanks for posting Oly. I dont know how to describe the sound it made, Kinda of a dry bindy sound. It was low on oil and I filled it before starting. I have had the pressure drop when the oil gets low when cornering at low rpm, but this sounded different. I started and ran it into town this weekend and it did great (8 miles one way), except the smoke. I have quit using it everyday in order to save the block for rebuilding. The oil was freshly changed so it wasnt dirty, thin oil. I dissembled the spare 235 this weekend and will try to find a machinist to get it going again. Thanks again.
Ralph