good chance you loosened up some heavy chit and it clogged the oil sump and it lost oil pressure.

seen it happen more than once......

 

I used a product made by chemtool in my ATV because it had water in the oil that wouldnt get totally removed every time i changed the oil. I poured her in, ran it for a few minutes per the instructions, and dumped the oil, since then ive never had a water issue.

 

it was fairly clean in there but there was som sort of coating on the intake cavity walls

 

what did the screen look like in the sump and why did the engine fail?

 

Hey Joe...I have a '77 LTD as well, with the 351W! Cool car huh? Here is my two cents. This problem is somewhat common on high-mileage motors, especially if your PCV system isn't working properly. My 351W from the same car as yours has some blowby issues, but nothing that I don't expect for a 30 year old vehicle that has been run hard all its life. I believe that Windsor-family engines seem to have more blow-by related issues than other families, but I don't know why and don't have a lot of facts to back that up.

I am of the opinion that nothing should go in a crankcase except oil and nothing else. As someone else on the forums once said, "sometimes that stuff is the only thing holding things together" and it's true. You get all that sludge and gunk built up, and it's normal - often times it doesn't hurt anything. But you put that engine cleaner crap in there and it gets loosened up, along with any other particles that were stuck in that sludge, and now that crud is running through your bearings. And an oil filter can NOT handle 30 years worth of gunk all of a sudden, and the pickup screen will be in even worse shape.

That sludge is normal and isn't going to hurt anything usually. It stays put. Your main concern for an old engine like that will be oil pressure. You don't have any solid proven facts to back up that it "would run better without that junk in there."

 

well said...........

 

one piston was ripped off the rod, and the rod was broken off the crank i turned the car off .... did not stall ...... and it was started again to drive in the driveway (uphill) to heavy to push

 

it might be able to be rebuilt

 

when sludge builds up in the motor it gets in between the bearings and other rotating ***, acts like sand paper grinds down the parts. if cleaned before it gets that bad then you saved the engine. but if not done in time then it wears out the rotating ***.
you dont know that everything is badly worn due to the oil is between everything and is actuelly keeping things tight. how sludge ends hurting engine is from too much of it has built up between the rotating ***, and then made everything too tight and the motor locks up. so when the motor let loose after cleaning was due too everything cleaned out and loosened it up some parts flopping around broke. such as piston coming off rod. sorry for bringing this out of the dead its something i wanted to say toanswer all questions.